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                                Warrant Agreement

                           Dated as of March 27, 2002

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         WARRANT AGREEMENT, dated as of March 27, 2002, between BioTime, Inc., a
California corporation (the "Company"), and Alfred D. Kingsley (the "Lender").

         The  Company  proposes to issue a Common  Share  Purchase  Warrant,  as
hereinafter described (the "Warrants"), to purchase up to an aggregate of 30,000
of its Common  Shares,  no par value (the "Common  Stock") (the shares of Common
Stock  issuable  upon exercise of the Warrants  being  referred to herein as the
"Warrant Shares"),  in connection with the Revolving Line of Credit Agreement of
even date (the "Credit Agreement"), between the Company and the Lender.

         In  consideration  of the foregoing and for the purpose of defining the
terms and  provisions of the Warrant and the respective  rights and  obligations
thereunder  of the  Company  and  each  registered  owner  of the  Warrant  (the
"Holder"), the Company and the Lender hereby agree as follows:

         SECTION 1. Issuance of Warrants;  Term of Warrants.  Concurrently  with
the  execution  and delivery of this  Agreement  and the Credit  Agreement,  the
Company is issuing and  delivering  to the Lender a Warrant to  purchase  30,000
Warrant  Shares,  which  Warrant  shall  be  represented  by  a  certificate  in
substantially  the  form of  Exhibit  A  hereto.  Subject  to the  terms of this
Agreement,  a Holder of any of such Warrant  (including  any Warrants into which
the Warrant may be divided) shall have the right,  which may be exercised at any
time  prior to 5:00  p.m.,  New York  Time on March 26,  2007  (the  "Expiration
Date"),  to purchase from the Company the number of fully paid and nonassessable
Warrant  Shares  which the Holder may at the time be entitled  to purchase  upon
exercise of any of such Warrant.

         SECTION 2. Transferability and Form of Warrant.

                  2.1  Registration.  The Warrant shall be numbered and shall be
registered on the books of the Company (the "Warrant  Register") as issued.  The
Company  and the  Warrant  Agent (if  appointed)  shall be entitled to treat the
Holder of any Warrant as the owner in fact  thereof for all  purposes  and shall
not be bound to  recognize  any  equitable  or other  claim or  interest in such
Warrant  on the part of any  other  person,  and  shall  not be  liable  for any
registration  of transfer of any Warrant which is registered or to be registered
in the name of a fiduciary  or the  nominee of a fiduciary  unless made with the
actual  knowledge that a fiduciary or nominee is committing a breach of trust in
requesting such  registration or transfer,  or with such knowledge of such facts
that its participation therein amounts to bad faith. The Warrant shall initially
be registered in the name of the Lender.

                  2.2 Restrictions on Exercise and Transfer. The Warrant may not
be exercised, sold, pledged, hypothecated,  transferred or assigned, in whole or
in part,  unless a registration  statement  under the Securities Act of 1933, as
amended (the "Act"), and under any applicable state securities laws is effective
therefor  or,  an  exemption  from  such  registration  is then  available.  Any
exercise, sale, pledge,  hypothecation,  transfer, or assignment in violation of
the  foregoing  restriction  shall be  deemed  null  and void and of no  binding
effect. The Company

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shall be entitled to obtain,  as a condition  precedent  to its  issuance of any
certificates  representing  Warrant Shares or any other securities issuable upon
any  exercise  of the  Warrant,  a letter or other  instrument  from the  Holder
containing  such  covenants,  representations  or  warranties  by such Holder as
reasonably  deemed necessary by Company to effect compliance by the Company with
the requirements of applicable federal and/or state securities laws.

                  2.3  Transfer.  Subject to Section 2.2,  the Warrant  shall be
transferable only on the Warrant Register upon delivery thereof duly endorsed by
the Holder or by his duly authorized attorney or representative,  or accompanied
by proper  evidence of  succession,  assignment or authority to transfer,  which
endorsement shall be guaranteed by a bank or trust company or a broker or dealer
which is a member of the National Association of Securities Dealers, Inc. In all
cases of transfer by an attorney, the original power of attorney, duly approved,
or a copy  thereof,  duly  certified,  shall be  deposited  and remain  with the
Company (or the Warrant Agent, if appointed).  In case of transfer by executors,
administrators,  guardians or other legal  representatives,  duly  authenticated
evidence  of  their  authority  shall be  produced,  and may be  required  to be
deposited  and remain with the Company (or the Warrant  Agent,  if appointed) in
its discretion. Upon any registration of transfer, the Company shall execute and
deliver (or if appointed, the Warrant Agent shall countersign and deliver) a new
Warrant or Warrants to the persons entitled thereto.

                  2.4  Form  of  Warrant.  The  text of the  Warrant  and of the
Purchase Form shall be  substantially as set forth in Exhibit A attached hereto.
The price per  Warrant  Share and the number of  Warrant  Shares  issuable  upon
exercise of each  Warrant  are  subject to  adjustment  upon the  occurrence  of
certain events, all as hereinafter  provided.  The Warrants shall be executed on
behalf of the Company by its Chairman of the Board, President or one of its Vice
Presidents,  under  its  corporate  seal  reproduced  thereon  attested  by  its
Secretary  or Assistant  Secretary.  The  signature of any such  officers on the
Warrants may be manual or facsimile,  provided,  however,  that the signature of
any  such  officers  must be  manual  until  such  time as a  Warrant  Agent  is
appointed.

                  Warrants  bearing  the  manual  or  facsimile   signatures  of
individuals  who were at any time the proper  officers of the Company shall bind
the Company, notwithstanding that such individuals or any one of them shall have
ceased to hold such offices  prior to the  delivery of such  Warrants or did not
hold such offices on the date of this Agreement.

                  In the event that the Company shall appoint a Warrant Agent to
act on its  behalf  in  connection  with the  division,  transfer,  exchange  or
exercise of  Warrants,  the Warrants  issued after the date of such  appointment
shall be dated as of the date of  countersignature  thereof by the Warrant Agent
upon  division,  exchange,  substitution  or  transfer.  Until  such time as the
Company shall appoint a Warrant Agent, Warrants shall be dated as of the date of
execution  thereof by the Company either upon initial issuance or upon division,
exchange, substitution or transfer.

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         SECTION 3.  Countersignature of Warrants. In the event that the Company
shall  appoint  a Warrant  Agent to act on its  behalf  in  connection  with the
division,  transfer, exchange or exercise of Warrants, the Warrants issued after
the date of such  appointment  shall be counter  signed by the Warrant Agent (or
any successor to the Warrant  Agent then acting as warrant  agent) and shall not
be valid for any purpose unless so countersigned. Warrants may be countersigned,
however,  by the Warrant Agent (or by its successor as warrant agent  hereunder)
and may be  delivered  by the Warrant  Agent,  notwithstanding  that the persons
whose manual or facsimile  signatures  appear thereon as proper  officers of the
Company   shall  have   ceased  to  be  such   officers  at  the  time  of  such
countersignature,  issuance or  delivery.  The Warrant  Agent (if so  appointed)
shall, upon written instructions of the Chairman of the Board, the President, an
Executive  or Senior Vice  President,  the  Treasurer or the  Controller  of the
Company,  countersign,  issue and deliver Warrants entitling the Holders thereof
to purchase not more than 30,000 Warrant Shares (subject to adjustment  pursuant
to Section 10 hereof) and shall  countersign  and deliver  Warrants as otherwise
provided in this Agreement.

         SECTION 4. Exchange of Warrant  Certificates.  Each Warrant certificate
may be  exchanged,  at the option of the Holder  thereof,  for  another  Warrant
certificate or Warrant  certificates  in different  denominations  entitling the
Holder or Holders thereof to purchase a like aggregate  number of Warrant Shares
as the  certificate  or  certificates  surrendered  then  entitle each Holder to
purchase.  Any Holder desiring to exchange a Warrant certificate or certificates
shall make such  request in writing  delivered  to the Company at its  principal
office (or, if a Warrant Agent is appointed,  the Warrant Agent at its principal
office) and shall surrender,  properly endorsed, the certificate or certificates
to be so exchanged. Thereupon, the Company (or, if appointed, the Warrant Agent)
shall  execute  and  deliver  to  the  person  entitled  thereto  a new  Warrant
certificate or certificates,  as the case may be, as so requested,  in such name
or names as such Holder shall designate.

         SECTION 5. Exercise of Warrants; Listing.

                  5.1  Exercise of  Warrants.  A Warrant may be  exercised  upon
surrender  of the  certificate  or  certificates  evidencing  the Warrants to be
exercised, together with the form of election to purchase on the reverse thereof
duly filled in and signed,  which  signature  shall be  guaranteed  by a bank or
trust  company  or a  broker  or  dealer  which  is a  member  of  the  National
Association of Securities Dealers,  Inc., to the Company at its principal office
(or if appointed, the principal office of the Warrant Agent) and upon payment of
the  Warrant  Price  (as  defined  in and  determined  in  accordance  with  the
provisions of Sections 9 and 10 hereof) to the Company (or if appointed,  to the
Warrant Agent for the account of the Company),  for the number of Warrant Shares
in respect of which such Warrants are then  exercised.  Payment of the aggregate
Warrant  Price  (defined  in  Section  9  herein)  shall  be  made in cash or by
certified or bank cashier's check.

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                  Subject to Section 6 hereof, upon the surrender of the Warrant
and payment of the Warrant Price as aforesaid, the Company (or if appointed, the
Warrant  Agent)  shall  cause to be issued  and  delivered  with all  reasonable
dispatch to or upon the written order of the Holder and in such name or names as
the Holder may designate,  a certificate or certificates  for the number of full
Warrant  Shares so purchased  upon the exercise of such  Warrant,  together with
cash,  as provided in Section 11 hereof,  in respect of any  fractional  Warrant
Shares otherwise issuable upon such surrender.  Such certificate or certificates
shall be deemed to have been  issued  and any person so  designated  to be named
therein shall be deemed to have become a holder of record of such Warrant Shares
as of the date of the  surrender  of such  Warrants  and  payment of the Warrant
Price, as aforesaid.  The rights of purchase represented by the Warrant shall be
exercisable,  at the election of the Holder thereof, either in full or from time
to time in part and, in the event that a certificate  evidencing  the Warrant is
exercised in respect of less than all of the Warrant Shares  purchasable on such
exercise  at any time  prior to the date of  expiration  of the  Warrant,  a new
certificate  evidencing the  unexercised  portion of the Warrant will be issued,
and the Warrant  Agent (if so  appointed)  is hereby  irrevocably  authorized to
countersign and to deliver the required new Warrant  certificate or certificates
pursuant  to the  provisions  of this  Section  and  Section 3  hereof,  and the
Company, whenever required by the Warrant Agent (if appointed),  will supply the
Warrant Agent with Warrant  certificates  duly executed on behalf of the Company
for such purpose.

                  5.2 Listing of Shares on  Securities  Exchange;  Exchange  Act
Registration.  The  Company  will  promptly  use its best  efforts  to cause the
Warrant  Shares to be listed,  subject to official  notice of  issuance,  on all
national  securities  exchanges  on which the  Common  Stock is listed and whose
rules and regulations  require such listing,  as soon as possible  following the
date hereof.

                  The Company will promptly notify the Holders in the event that
the Company  plans to register the  Warrants  with the  Securities  and Exchange
Commission under the Securities  Exchange Act of 1934, as amended (the "Exchange
Act").

         SECTION 6. Payment of Taxes. The Company will pay all documentary stamp
taxes, if any,  attributable to the initial  issuance of Warrant Shares upon the
exercise of Warrants;  provided, however, that the Company shall not be required
to pay any tax or taxes which may be payable in respect of any transfer involved
in the issue or delivery of any Warrant or certificates  for Warrant Shares in a
name other than that of the registered Holder of such Warrants.

         SECTION  7.  Mutilated  or  Missing  Warrants.   In  case  any  of  the
certificates  evidencing  the  Warrants  shall be  mutilated,  lost,  stolen  or
destroyed,  the  Company  may in its  discretion  issue  and  deliver  (and,  if
appointed,  the Warrant  Agent shall  countersign  and  deliver) in exchange and
substitution for and upon cancellation of the mutilated Warrant certificate,  or
in  lieu of and  substitution  for  the  Warrant  certificate  lost,  stolen  or
destroyed,  a new Warrant  certificate  of like tenor,  but only upon receipt of
evidence  reasonably  satisfactory  to the Company and the Warrant  Agent (if so
appointed) of such loss,  theft or  destruction of such

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Warrant and an indemnity or bond, if requested,  also reasonably satisfactory to
them. An applicant for such a substitute  Warrant  certificate shall also comply
with such other reasonable  regulations and pay such other reasonable charges as
the Company (or the Warrant Agent, if so appointed) may prescribe.

         SECTION 8. Reservation of Warrant Shares;  Purchase and Cancellation of
Warrants.

                  8.1 Reservation of Warrant  Shares.  There have been reserved,
and the Company shall at all times keep reserved,  out of its authorized  Common
Stock, a number of shares of Common Stock sufficient to provide for the exercise
of the  rights of  purchase  represented  by the  outstanding  Warrants  and any
additional Warrants issuable hereunder.  The Transfer Agent for the Common Stock
and every  subsequent  transfer  agent for any shares of the  Company's  capital
stock issuable upon the exercise of any of the rights of purchase aforesaid will
be  irrevocably  authorized  and directed at all times to reserve such number of
authorized shares as shall be required for such purpose. The Company will keep a
copy of this  Agreement on file with the Transfer Agent for the Common Stock and
with every  subsequent  transfer  agent for any shares of the Company's  capital
stock  issuable upon the exercise of the rights of purchase  represented  by the
Warrants.  The Warrant Agent,  if appointed,  will be irrevocably  authorized to
requisition  from time to time from such Transfer  Agent the stock  certificates
required to honor outstanding  Warrants upon exercise thereof in accordance with
the terms of this  Agreement.  The Company will supply such Transfer  Agent with
duly executed stock certificates for such purposes and will provide or otherwise
make  available  any cash which may be payable as provided in Section 11 hereof.
The  Company  will  furnish  such  Transfer  Agent  a  copy  of all  notices  of
adjustments  and  certificates  related  thereto,  transmitted  to  each  Holder
pursuant to subsection 10.3 hereof.

                  8.2  Purchase of Warrants by the  Company.  The Company  shall
have the right,  except as limited by law, other agreements or herein,  with the
consent of the Holder,  to purchase or otherwise acquire Warrants at such times,
in such manner and for such consideration as it may deem appropriate.

                  8.3  Cancellation of Warrants.  In the event the Company shall
purchase or otherwise  acquire  Warrants,  the same shall thereupon be cancelled
and  retired.  The  Warrant  Agent (if so  appointed)  shall  cancel any Warrant
surrendered  for  exchange,  substitution,  transfer  or exercise in whole or in
part.

         SECTION 9.  Warrant  Price.  Subject  to any  adjustments  required  by
Section  10  hereof,  the  price  per  share at which  Warrant  Shares  shall be
purchasable  upon  exercise  of a Warrant  (as to any  particular  Warrant,  the
"Warrant Price") shall be Four Dollars ($4.00) per share.

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         SECTION 10.  Adjustment of Warrant Price and Number of Warrant  Shares.
The number and kind of securities  purchasable upon the exercise of each Warrant
and the Warrant Price shall be subject to adjustment  from time to time upon the
happening of certain events, as hereinafter defined.

                  10.1  Adjustments.  The number of Warrant  Shares  purchasable
upon the  exercise of each  Warrant  and the  Warrant  Price shall be subject to
adjustment as follows:

                           (a) In the  event  that the  Company  shall (i) pay a
dividend in shares of Common  Stock or make a  distribution  in shares of Common
Stock, (ii) subdivide its outstanding  shares of Common Stock, (iii) combine its
outstanding  shares of Common  Stock  into a smaller  number of shares of Common
Stock or (iv) reclassify or change  (including a change to the right to receive,
or a change  into,  as the case may be (other  than with  respect to a merger or
consolidation  pursuant to the exercise of appraisal  rights),  shares of stock,
other securities,  property,  cash or any combination  thereof) its Common Stock
(including   any  such   reclassification   or  change  in  connection   with  a
consolidation or merger in which the Company is the surviving corporation),  the
number of Warrant Shares  purchasable upon exercise of each Warrant  immediately
prior  thereto  shall be  adjusted so that the Holder of each  Warrant  shall be
entitled to receive the kind and number of Warrant Shares or other securities of
the Company or other property which he would have owned or have been entitled to
receive  after the  happening  of any of the events  described  above,  had such
Warrant been exercised  immediately  prior to the happening of such event or any
record date with respect thereto.  An adjustment made pursuant to this paragraph
(a) shall become  effective  immediately  after the effective date of such event
retroactive to the record date, if any, for such event.

                           (b) In case the Company shall issue  rights,  options
or warrants to all holders of its outstanding  Common Stock,  without any charge
to such holders,  entitling  them to subscribe for or purchase  shares of Common
Stock at a price per share  which is lower at the record  date  mentioned  below
than the then  current  market  price per share of Common  Stock (as  defined in
paragraph (d) below),  the number of Warrant Shares thereafter  purchasable upon
the exercise of each Warrant shall be determined  by  multiplying  the number of
Warrant  Shares  theretofore  purchasable  upon  exercise  of each  Warrant by a
fraction,  of which the numerator  shall be the number of shares of Common Stock
outstanding on the date of issuance of such rights, options or warrants plus the
number of additional shares of Common Stock offered for subscription or purchase
in  connection  with  such  rights,  options  or  warrants,  and  of  which  the
denominator  shall be the number of shares of Common  Stock  outstanding  on the
date of issuance of such rights,  options or warrants  plus the number of shares
which the aggregate offering price of the total number of shares of Common Stock
so offered would  purchase at the current market price per share of Common Stock
at such record date. Such adjustment shall be made whenever such rights, options
or warrants are issued, and shall become effective  immediately after the record
date for the  determination  of  stockholders  entitled to receive  such rights,
options or warrants.

                           (c) In  case  the  Company  shall  distribute  to all
holders of its  shares of Common  Stock,  (including  any  distribution  made in
connection  with a merger in which the  Company is the  surviving  corporation),
evidences  of  its  indebtedness  or  assets   (excluding  cash,   dividends  or
distributions  payable  out of  consolidated  earnings  or  earned  surplus  and
dividends  or  distributions  referred  to in  paragraph  (a)  above) or rights,
options or warrants,  or convertible or exchangeable  securities  containing the
right to  subscribe  for or purchase  shares of Common

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Stock  (excluding  those referred to in paragraph (b) above),  then in each case
the number of Warrant Shares  thereafter  purchasable  upon the exercise of each
Warrant  shall be  determined  by  multiplying  the  number  of  Warrant  Shares
theretofore  purchasable  upon the  exercise of each  Warrant by a fraction,  of
which the numerator  shall be the then current  market price per share of Common
Stock (as defined in paragraph (d) below) on the date of such distribution,  and
of which the  denominator  shall be the then  current  market price per share of
Common Stock,  less the then fair value (as determined by the Board of Directors
of the Company or, in the case of Warrants  held by the Lender,  an  independent
investment  banker  which  shall be mutually  agreeable  to the  parties,  whose
determination,  in each case,  shall be conclusive) of the portion of the assets
or evidences of  indebtedness  so  distributed or of such  subscription  rights,
options  or  warrants,  or  of  such  convertible  or  exchangeable   securities
applicable to one share of Common Stock.  Such adjustment shall be made whenever
any such  distribution  is  made,  and  shall  become  effective  on the date of
distribution   retroactive  to  the  record  date  for  the   determination   of
shareholders entitled to receive such distribution.

                           (d)  For  the  purpose  of  any   computation   under
paragraphs  (b) and (c) of this Section,  the current  market price per share of
Common  Stock at any date shall be the average of the daily last sale prices for
the 20 consecutive trading days ending one trading day prior to the date of such
computation.  The closing  price for each day shall be the last  reported  sales
price regular way or, in case no such reported sale takes place on such day, the
average of the  closing bid and asked  prices  regular way for such day, in each
case on the principal national securities exchange on which the shares of Common
Stock are listed or  admitted  to trading  or, if not so listed or  admitted  to
trading,  the last sale price of the Common  Stock on the Nasdaq Stock Market or
any comparable system. If the current market price of the Common Stock cannot be
so determined,  the Board of Directors of the Company shall reasonably determine
the current market price on the basis of such quotations as are available.

                           (e) No  adjustment  in the number of  Warrant  Shares
purchasable  hereunder shall be required unless such adjustment would require an
increase  or  decrease  of at least one  percent  (1%) in the  number of Warrant
Shares purchasable upon the exercise of each Warrant;  provided,  however,  that
any  adjustments  which by reason of this  paragraph  (e) are not required to be
made  shall  be  carried  forward  and  taken  into  account  in any  subsequent
adjustment. All calculations shall be made with respect to the number of Warrant
Shares purchasable  hereunder,  to the nearest tenth of a share and with respect
to the Warrant Price payable hereunder, to the nearest whole cent.

                           (f) Whenever the number of Warrant Shares purchasable
upon the exercise of each Warrant is adjusted,  as herein provided,  the Warrant
Price  payable upon  exercise of each Warrant  shall be adjusted by  multiplying
such Warrant Price immediately prior to such adjustment by a fraction,  of which
the  numerator  shall be the  number  of  Warrant  Shares  purchasable  upon the
exercise of each Warrant immediately prior to such adjustment,  and of which the
denominator  shall be the  number  of  Warrant  Shares  purchasable  immediately
thereafter.

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                           (g) No  adjustment  in the number of  Warrant  Shares
purchasable  upon the exercise of each Warrant need be made under paragraphs (b)
and (c) if the Company  issues or  distributes  to each  Holder of Warrants  the
rights  options,   warrants,  or  convertible  or  exchangeable  securities,  or
evidences of indebtedness or assets referred to in those  paragraphs  which each
Holder of Warrants  would have been  entitled to receive had the  Warrants  been
exercised  prior to the  happening of such event or the record date with respect
thereto. No adjustment need be made for a change in the par value of the Warrant
Shares.

                           (h) For the purpose of this subsection 10.1, the term
"shares of Common  Stock"  shall mean (i) the class of stock  designated  as the
Common  Stock of the  Company at the date of this  Agreement,  or (ii) any other
class of stock resulting from successive  changes or  reclassifications  of such
shares  consisting  solely of changes in par value,  or from par value to no par
value,  or from no par value to par value.  In the event that at any time,  as a
result of an adjustment made pursuant to paragraph (a) above,  the Holders shall
become  entitled to purchase any  securities of the Company other than shares of
Common Stock,  thereafter  the number of such other shares so  purchasable  upon
exercise of each  Warrant and the Warrant  Price of such shares shall be subject
to adjustment from time to time in a manner and on terms as nearly equivalent as
practicable  to the provisions  with respect to the Warrant Shares  contained in
paragraphs  (a) through  (i),  inclusive,  and the  provisions  of Section 5 and
subsections  10.2 through 10.5,  inclusive,  with respect to the Warrant Shares,
shall apply on like terms to any such other securities.

                           (i)  Upon  the  expiration  of any  rights,  options,
warrants or  conversion  or exchange  privileges,  if any thereof shall not have
been exercised,  the Warrant Price and the number of Warrant Shares  purchasable
upon the exercise of each Warrant shall, upon such expiration, be readjusted and
shall  thereafter be such as it would have been had it been originally  adjusted
(or had the original adjustment not been required, as the case may be) as if (A)
the only shares of Common  Stock so issued were the shares of Common  Stock,  if
any, actually issued or sold upon the exercise of such rights, options, warrants
or  conversion or exchange  rights and (B) such shares of Common Stock,  if any,
were issued or sold for the consideration  actually received by the Company upon
such exercise plus the aggregate consideration, if any, actually received by the
Company for the issuance, sale or grant of all such rights, options, warrants or
conversion or exchange rights whether or not exercised.

                  10.2 Voluntary  Adjustment by the Company.  The Company may at
its option, at any time during the term of the Warrants, reduce the then current
Warrant Price to any amount deemed  appropriate by the Board of Directors of the
Company.

                  10.3  Notice of  Adjustment.  Whenever  the  number of Warrant
Shares  purchasable  upon the exercise of each  Warrant or the Warrant  Price of
such Warrant Shares is adjusted,  as herein  provided,  the Company shall, or in
the event that a Warrant Agent is appointed, the Company shall cause the Warrant
Agent promptly to, mail by first class,  postage prepaid,  to each Holder notice
of such  adjustment  or  adjustments.  Such notice shall set forth the number of
Warrant  Shares  purchasable  upon the  exercise of each Warrant and the Warrant
Price

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of such Warrant Shares after such adjustment, setting forth a brief statement of
the facts  requiring such  adjustment and setting forth the computation by which
such adjustment was made.

                  10.4 No  Adjustment  for  Dividends.  Except  as  provided  in
subsection  10.1, no adjustment in respect of any dividends shall be made during
the term of a Warrant or upon the exercise of a Warrant.

                  10.5    Preservation   of   Purchase   Rights   Upon   Merger,
Consolidation,  etc. In case of any  consolidation of the Company with or merger
of the Company  into  another  corporation  or in case of any sale,  transfer or
lease to another  corporation  of all or  substantially  all the property of the
Company,  the Company or such successor or purchasing  corporation,  as the case
may be,  shall  execute  an  agreement  that each  Holder  shall  have the right
thereafter,  upon such Holder's election, either (i) upon payment of the Warrant
Price in effect  immediately  prior to such action, to purchase upon exercise of
each  Warrant the kind and amount of shares and other  securities  and  property
(including  cash)  which he would  have owned or have been  entitled  to receive
after the happening of such consolidation,  merger,  sale, transfer or lease had
such Warrant been  exercised  immediately  prior to such action (such shares and
other  securities and property  (including  cash) being referred to as the "Sale
Consideration") or (ii) to receive, in cancellation of such Warrant (and in lieu
of paying the Warrant price and exercising such Warrant), the Sale Consideration
less a portion  thereof having a fair market value (as reasonably  determined by
the Company) equal to the Warrant Price (it being  understood  that, if the Sale
Consideration  consists  of more than one type of shares,  other  securities  or
property,  the amount of each type of shares, other securities or property to be
received  shall  be  reduced  proportionately);   provided,   however,  that  no
adjustment  in respect of  dividends,  interest or other  income on or from such
shares or other  securities  and  property  shall be made  during  the term of a
Warrant or upon the exercise of a Warrant. The Company shall mail by first class
mail,  postage  prepaid,  to each  Holder,  notice of the  execution of any such
agreement.  Such  agreement  shall  provide for  adjustments,  which shall be as
nearly equivalent as may be practicable to the adjustments  provided for in this
Section 10. The  provisions of this  subsection  10.5 shall  similarly  apply to
successive  consolidations,  mergers,  sales,  transfers or leases.  The Warrant
Agent (if appointed) shall be under no duty or  responsibility  to determine the
correctness  of any provisions  contained in any such agreement  relating to the
kind or amount of shares of stock or other  securities  or  property  receivable
upon  exercise of Warrants or with  respect to the method  employed and provided
therein for any  adjustments  and shall be entitled to rely upon the  provisions
contained in any such agreement.

                  10.6 Statement on Warrants. Irrespective of any adjustments in
the Warrant Price or the number or kind of shares  purchasable upon the exercise
of the Warrants, Warrants issued before or after such adjustment may continue to
express  the same  price and  number  and kind of  shares  as are  stated in the
Warrants initially issuable pursuant to this Agreement.

         SECTION 11. Fractional Interests.  The Company shall not be required to
issue  fractional  Warrant Shares on the exercise of Warrants.  If more than one
Warrant  shall be  presented  for  exercise in full at the same time by the same
Holder,  the number of full  Warrant

                                       9

<PAGE>


Shares which shall be issuable  upon the exercise  thereof  shall be computed on
the basis of the aggregate  number of Warrant Shares  purchasable on exercise of
the Warrants so presented.  If any fraction of a Warrant Share would, except for
the  provisions  of this  Section 11, be issuable on the exercise of any Warrant
(or specified portion thereof), the Company shall pay an amount in cash equal to
the average of the daily  closing sale prices  (determined  in  accordance  with
paragraph  (d) of  subsection  10.1)  per  share  of  Common  Stock  for  the 20
consecutive trading days ending one trading day prior to the date the Warrant is
presented for exercise, multiplied by such fraction.

         SECTION  12. No Rights as  Shareholders;  Notices to  Holders.  Nothing
contained  in this  Agreement  or in any of the  Warrants  shall be construed as
conferring upon the Holders or their transferees the right to vote or to receive
dividends or to consent or to receive notice as  shareholders  in respect of any
meeting of  shareholders  for the  election of  directors  of the Company or any
other matter,  or any rights  whatsoever  as  shareholders  of the Company.  If,
however,  at any time prior to the expiration of the Warrants and prior to their
exercise, any of the following events shall occur:

                  (a) the  Company  shall  declare any  dividend  payable in any
securities upon its shares of Common Stock or make any distribution  (other than
a regular cash dividend, as such dividend may be increased from time to time, or
a dividend  payable in shares of Common  Stock) to the  holders of its shares of
Common Stock; or

                  (b) the  Company  shall  offer to the holders of its shares of
Common Stock on a pro rata basis any cash,  additional shares of Common Stock or
other  securities  of the Company or any right to subscribe  for or purchase any
thereof; or

                  (c) a  dissolution,  liquidation  or winding up of the Company
(other than in connection with a consolidation,  merger, sale, transfer or lease
of all  or  substantially  all  of its  property,  assets,  and  business  as an
entirety) shall be proposed,

then in any one or more of said  events  the  Company  shall (a) give  notice in
writing of such event as provided  in Section 14 hereof and (b) if the  Warrants
have been  registered  pursuant  to the Act,  cause  notice of such  event to be
published once in The Wall Street  Journal  (national  edition),  such giving of
notice and  publication to be completed at least 10 days prior to the date fixed
as a record date or the date of closing the transfer books for the determination
of the  stockholders  entitled to such dividend,  distribution,  or subscription
rights  or for  the  determination  of  stockholders  entitled  to  vote on such
proposed  dissolution,  liquidation  or winding up or the date of  expiration of
such offer.  Such notice  shall  specify such record date or the date of closing
the transfer  books or the date of  expiration,  as the case may be.  Failure to
publish, mail or receive such notice or any defect therein or in the publication
or mailing  thereof  shall not affect the  validity of any action in  connection
with such  dividend,  distribution  or  subscription  rights,  or such  proposed
dissolution, liquidation or winding up, or such offer.

                                       10

<PAGE>


         SECTION 13.  Appointment of Warrant Agent.  At such time as the Company
shall register Warrants under the Act, the Company shall appoint a Warrant Agent
to act on behalf of the  Company  in  connection  with the  issuance,  division,
transfer  and  exercise  of  Warrants.  At such time as the  Company  appoints a
Warrant  Agent,  the Company shall enter into a new Warrant  Agreement  with the
Warrant  Agent   pursuant  to  which  all  new  Warrants  will  be  issued  upon
registration of transfer or division,  which will reflect the appointment of the
Warrant Agent, as well as additional customary provisions as shall be reasonably
requested by the Warrant Agent in connection with the performance of its duties.
In the event that a Warrant Agent is  appointed,  the Company shall (i) promptly
notify the Holders of such  appointment  and the place  designated for transfer,
exchange and exercise of the Warrants, and (ii) take such steps as are necessary
to insure that Warrants  issued prior to such  appointment  may be exchanged for
Warrants countersigned by the Warrant Agent.

         SECTION 14.  Notices;  Principal  Office.  Any notice  pursuant to this
Agreement  by  the  Company  or by  any  Holder  to  the  Warrant  Agent  (if so
appointed),  or by the Warrant  Agent (if so  appointed) or by any Holder to the
Company,  shall be in writing and shall be delivered in person,  or mailed first
class, postage prepaid (a) to the Company, at its office,  Attention:  President
or (b) to the  Warrant  Agent,  at its  offices  as  designated  at the time the
Warrant Agent is appointed.  The address of the principal  office of the Company
is 935 Pardee Street,  Berkeley,  California  94710.  Each party hereto may from
time to time change the address to which  notices to it are to be  delivered  or
mailed hereunder by notice to the other party.

                  Any notice mailed pursuant to this Agreement by the Company or
the Warrant  Agent to the Holders  shall be in writing and shall be mailed first
class,  postage  prepaid,  or  otherwise  delivered,  to such  Holders  at their
respective  addresses on the books of the Company or the Warrant  Agent,  as the
case may be.

         SECTION 15.  Successors.  Except as  expressly  provided  herein to the
contrary,  all the  covenants  and  provisions  of this  Agreement by or for the
benefit of the  Company  and the Lender  shall bind and inure to the  benefit of
their respective successors and permitted assigns hereunder.

         SECTION 16. Merger or  Consolidation  of the Company.  The Company will
not  merge or  consolidate  with or  into,  or sell,  transfer  or lease  all or
substantially all of its property to, any other corporation unless the successor
or  purchasing  corporation,  as the  case  may be (if not the  Company),  shall
expressly assume, by supplemental  agreement,  the due and punctual  performance
and  observance of each and every covenant and condition of this Agreement to be
performed and observed by the Company.

                                       11

<PAGE>


         SECTION 17. Investment Representations.  Lender represents and warrants
to BioTime that:

                  17.1 Lender has received the  Company's  financial  statements
for the year ended on December  31,  2001,  as will be included in its Form 10-K
for such fiscal year,  its annual  report on Form 10-K for the fiscal year ended
December 31, 2000, and quarterly  report on Form 10-Q for the fiscal quarter and
nine months ended  September 30, 2001 (the  "Disclosure  Documents").  Lender is
relying on the  information  provided in the  Disclosure  Documents or otherwise
communicated  to Lender in writing by the Company.  Lender has not relied on any
statement or representations inconsistent with those contained in the Disclosure
Documents.  Lender has had a  reasonable  opportunity  to ask  questions  of and
receive answers from the executive officers and directors of the Company, or one
or more  of its  officers,  concerning  the  Company  and to  obtain  additional
information,  to the extent possessed or obtainable without  unreasonable effort
or expense, necessary to verify the information in the Disclosure Documents. All
such questions have been answered to Lender's satisfaction;

                  17.2  Lender  understands  that the  Warrant  and the  Warrant
Shares  are  being  offered  and  sold  without  registration  under  the Act or
qualification  under the California  Corporate  Securities Law of 1968, or under
the laws of other states, in reliance upon the exemptions from such registration
and qualification requirements for non-public offerings. Lender acknowledges and
understands  that the availability of the aforesaid  exemptions  depends in part
upon the accuracy of certain of the representations, declarations and warranties
contained  herein,  which  Lender  hereby makes with the intent that they may be
relied  upon by the  Company  and its  officers  and  directors  in  determining
Lender's suitability to acquire the Warrant. Lender understands and acknowledges
that no federal,  state or other agency has reviewed or endorsed the offering of
the Warrant or the Warrant Shares or made any finding or determination as to the
fairness of the offering or  completeness  of the  information in the Disclosure
Documents;

                  17.3  Lender  understands  that the  Warrant  and the  Warrant
Shares may not be offered,  sold, or transferred in any manner,  and the Warrant
may not be exercised,  unless  subsequently  registered under the Act, or unless
there is an exemption from such  registration  available for such offer, sale or
transfer;

                  17.4 Lender has such knowledge and experience in financial and
business  matters to enable Lender to utilize the  information  contained in the
Disclosure  Documents,  or  otherwise  made  available to Lender to evaluate the
merits and risks of an investment  in the Warrant and the Warrant  Shares and to
make an informed investment decision with respect thereto.

                  17.5 Lender is acquiring  the Warrant  solely for Lender's own
account and for long-term  investment  purposes,  and not with a view to, or for
sale in connection with, any distribution of the Warrant or Warrant Shares; and

                                       12

<PAGE>


                  17.6  Lender  is an  "accredited  investor,"  as such  term is
defined in Regulation D promulgated under the Act.

         SECTION 18. Registration Rights.

                  18.1 The Company agrees, at its expense,  upon written request
from the Lender,  to register  under the Act, the Warrant and the Warrant Shares
and to take such other  actions as may be necessary to allow the Warrant and the
Warrant Shares to be freely tradable,  without restrictions,  in compliance with
all regulatory  requirements.  A written request for registration  shall specify
the quantity of the Warrant Shares intended to be sold, the plan of distribution
and the identity of the sellers,  which may include the Lender and  assignees of
its rights hereunder  (collectively,  "Selling Securities Holders"), and whether
the  registration  shall be pursuant  to an  underwritten  public  offering or a
"shelf'  registration  pursuant to Rule 415 (or similar rule that may be adopted
by the Securities and Exchange  Commission).  The Company shall not be obligated
to file more than two such  registration  statements,  other  than  registration
statements  on Form S-3.  The Company  shall keep such  registration  statements
effective  for a period  of at  least  nine  months,  except  that  registration
statements  on Form S-3 shall be kept  effective  for at least  three years ( or
such  lesser  period  as the  parties  may  agree,  but in no event  beyond  the
completion of the  distribution or distributions  being made pursuant  thereto).
The Company  shall  utilize Form S-3 if it  qualifies  for such use. The Company
shall make all filings required with respect to the registration  statements and
will use its best efforts to cause such filings to become effective, so that the
Warrant and Warrant Shares being registered shall be registered or qualified for
sale under the  securities  or blue sky laws of such  jurisdictions  as shall be
reasonably  appropriate  for  distribution  of the Warrant  and  Warrant  Shares
covered by the registration  statement.  The Company will furnish to the Selling
Securities  Holders  such  numbers  of  copies  of  a  prospectus,  including  a
preliminary prospectus,  in conformity with the requirements of the Act and such
other related documents as the Selling Securities Holders may reasonably request
in order to effect the sale of the  Warrant and  Warrant  Shares.  To effect any
offering  pursuant to a registration  statement under this Section,  the Company
shall  enter  into  an  agreement  containing   customary   representations  and
warranties, and indemnification and contribution provisions, all for the benefit
of  Selling  Securities  Holders,  and,  in the case of an  Underwritten  public
offering. an underwriting  agreement with an investment banking firm selected by
the Lender and reasonably  acceptable to the Company,  containing such customary
representations and warranties, and indemnification and contribution provisions

                  18.2 If, at any time, the Company  proposes to register any of
its securities  under the Act (otherwise  than pursuant to Section 18.1 above or
on a Form S-8 if such form  cannot be used for  registration  of the  Warrant or
Warrant  Shares  pursuant  to its  terms),  the  Company  shall,  as promptly as
practicable,  give written  notice to the Lender.  The Company  shall include in
such  registration  statement the Warrant and any Warrant Shares  proposed to be
sold by the Selling Securities Holders.  Notwithstanding  the foregoing,  if the
offering of the  Company's  securities is to be made through  underwriters,  the
Company  shall not be required to include the Warrant and Warrant  Shares if and
to the extent that the managing  underwriter  reasonably  believes in good faith
that such inclusion would  materially  adversely affect such

                                       13

<PAGE>


offering  unless the Selling  Securities  Holders agree to postpone  their sales
until 10 days after the distribution is completed.

                  18.3  The  Company  shall  pay the  cost  of the  registration
statements filed pursuant to this Agreement,  including  without  limitation all
registration and filing fees, fees and expenses of compliance with securities or
blue sky laws (including  counsel's fees and expenses in connection  therewith),
printing  expenses,  messenger and delivery  expenses,  internal expenses of the
Company,  listing  fees and  expenses,  and fees and  expenses of the  Company's
counsel,  independent  accountants and other persons retained or employed by the
Company.  Selling  Securities  Holders  shall  pay  any  underwriters  discounts
applicable to the Warrant and Warrant Shares.

         SECTION 19. Legends. The Warrants and Warrant Shares issued pursuant to
this Agreement shall bear an appropriate  legend,  conspicuously  disclosing the
restrictions  on exercise and transfer under Section 2.2 of this Agreement until
the same are registered for sale under the Act. The Company agrees that upon the
sale of the Warrant and Warrant Shares  pursuant to a registration  statement or
an exemption, upon the presentation of the certificates containing such a legend
to it's transfer agent,  it will remove such legend.  The Company further agrees
to remove the legend at such time as registration  under the Act shall no longer
be required.

         SECTION 20.  Applicable  Law. This  Agreement  and each Warrant  issued
hereunder  shall be governed by and construed in accordance with the laws of the
State of California, without giving effect to principles of conflict of laws.

         SECTION 21. Benefits of this Agreement. Nothing in this Agreement shall
be construed to give to any person or  corporation  other than the Company,  the
Warrant  Agent (if  appointed)  and the  Holders any legal or  equitable  right,
remedy or claim under this  Agreement;  but this Agreement shall be for the sole
and exclusive  benefit of the Company,  the Warrant Agent and the Holders of the
Warrants.

         SECTION 22. Counterparts.  This Agreement may be executed in any number
of counterparts and each of such  counterparts  shall for all purposes be deemed
to be an original,  and all such counterparts shall together  constitute but one
and the same instrument.

         SECTION 23.  Captions.  The captions of the Sections and subsections of
this  Agreement  have been  inserted  for  convenience  only and  shall  have no
substantive effect.

                                       14

<PAGE>


         IN WITNESS WHEREOF, the parties hereto have caused this Agreement to be
duly executed, all as of the day and year first above written.

                                            BIOTIME, INC.


                                            By: ________________________________
                                               Name: Paul Segall, Ph.D
                                               Title: Chairman and Chief
                                                      Executive Officer


Attest:

By: ______________________________
    Name: Judith Segall
    Title: Secretary

                                            ____________________________________
                                                       Alfred D. Kingsley

                                       15

<PAGE>


                                                                       EXHIBIT A

         THIS WARRANT HAS NOT BEEN REGISTERED  UNDER THE SECURITIES ACT OF 1933,
AS AMENDED,  OR UNDER  APPLICABLE STATE SECURITIES LAWS. THIS WARRANT MAY NOT BE
EXERCISED, SOLD, PLEDGED, HYPOTHECATED,  TRANSFERRED OR ASSIGNED EXCEPT UNDER AN
EFFECTIVE  REGISTRATION STATEMENT UNDER SUCH ACT AND APPLICABLE STATE SECURITIES
LAWS, UNLESS AN EXEMPTION FROM SUCH REGISTRATION IS AVAILABLE.

               VOID AFTER 5:00 P.M. NEW YORK TIME, March 26, 2007


Certificate No. ______                                       Warrant to Purchase
                                                       [Insert number of Shares]
                                                          Shares of Common Stock


                                  BIOTIME, INC.
                         COMMON SHARE PURCHASE WARRANTS

         This  certifies  that, for value  received,  [Insert name of Holder] or
registered assigns (the "Holder"),  is entitled to purchase from BioTime, Inc. a
California  corporation (the  "Company"),  at a purchase price per share [Insert
Warrant Price determined pursuant to Sections 9 and 10 of the Warrant Agreement]
(the "Warrant  Price"),  the number of its Common Shares, no par value per share
(the  "Common  Stock"),  shown  above.  The  number of shares  purchasable  upon
exercise of the Common Share Purchase  Warrants (the "Warrants") and the Warrant
Price are  subject to  adjustment  from time to time as set forth in the Warrant
Agreement  referred to below.  Outstanding  Warrants not exercised prior to 5:00
p.m., New York time, on March 26, 2007 shall thereafter be void.

         Subject to restriction specified in the Warrant Agreement, Warrants may
be exercised  in whole or in part by  presentation  of this Warrant  Certificate
with the Purchase Form on the reverse side hereof duly executed, which signature
shall be  guaranteed by a bank or trust company or a broker or dealer which is a
member of the National Association of Securities Dealers, Inc., and simultaneous
payment of the Warrant  Price (or as otherwise set forth in Section 10.5) of the
Warrant  Agreement at the principal office of the Company (or if a Warrant Agent
is appointed,  at the principal  office of the Warrant  Agent).  Payment of such
price shall be made in cash or by certified or bank cashier's check. As provided
in the Warrant  Agreement,  the  Warrant  Price and the number or kind of shares
which may be  purchased  upon the  exercise  of the  Warrant  evidenced  by this
Warrant  Certificate  are,  upon the  happening  of certain  events,  subject to
modification and adjustment.

                                       16

<PAGE>


         This  Warrant  Certificate  is issued  under and in  accordance  with a
Warrant  Agreement  dated as of March 27, 2002 between the Company and Alfred D.
Kingsley  and is subject to the terms and  provisions  contained  in the Warrant
Agreement,  to all of which the Holder of this Warrant Certificate by acceptance
of this Warrant  Certificate  consents.  A copy of the Warrant  Agreement may be
obtained by the Holder hereof upon written request to the Company.  In the event
that  pursuant  to  Section  13 of the  Warrant  Agreement  a  Warrant  Agent is
appointed and a new warrant  agreement entered into between the Company and such
Warrant  Agent,  then such new warrant  agreement  shall  constitute the Warrant
Agreement for purposes  hereof and this Warrant  Certificate  shall be deemed to
have been issued pursuant to such new warrant agreement.

         Upon any  partial  exercise of the Warrant  evidenced  by this  Warrant
Certificate,  there  shall  be  issued  to  the  Holder  hereof  a  new  Warrant
Certificate  in respect of the  shares of Common  Stock as to which the  Warrant
evidenced  by this  Warrant  Certificate  shall  not have been  exercised.  This
Warrant  Certificate  may be  exchanged  at the  office of the  Company  (or the
Warrant Agent, if appointed) by surrender of this Warrant  Certificate  properly
endorsed  either  separately  or in  combination  with one or more other Warrant
Certificates  for one or more new Warrant  Certificates  evidencing the right of
the  Holder  thereof  to  purchase  the  aggregate  number  of  shares  as  were
purchasable on exercise of the Warrants evidenced by the Warrant  Certificate or
Certificates exchanged. No fractional shares will be issued upon the exercise of
any  Warrant,  but the Company  will pay the cash value  thereof  determined  as
provided in the Warrant Agreement.  This Warrant  Certificate is transferable at
the office of the Company (or the Warrant Agent, if appointed) in the manner and
subject to the limitations set forth in the Warrant Agreement.

         The Holder hereof may be treated by the Company,  the Warrant Agent (if
appointed)  and all other persons  dealing with this Warrant  Certificate as the
absolute owner hereof for any purpose and as the person entitled to exercise the
rights  represented  hereby,  or to the  transfer  hereof  on the  books  of the
Company, any notice to the contrary notwithstanding,  and until such transfer on
such books,  the Company (and the Warrant  Agent,  if  appointed)  may treat the
Holder hereof as the owner for all purposes.

         Neither the Warrant nor this Warrant Certificate entitles any Holder to
any of the rights of a stockholder of the Company.

         [This  Warrant  Certificate  shall not be valid or  obligatory  for any
purpose until it shall have been countersigned by the Warrant Agent.]*

                                       17

<PAGE>


DATED:

                                                     BIOTIME, INC.


(Seal)                                               By:________________________

                                                     Title:

Attest:____________________


[COUNTERSIGNED:

                                    ,
WARRANT AGENT


By: _________________________________]*
         Authorized Signature

--------------------
*        To be part of the Warrant only after the appointment of a Warrant Agent
         pursuant to Section 13 of the Warrant Agreement.

                                       18

<PAGE>


                                  PURCHASE FORM

                    (To be executed upon exercise of Warrant)


To BioTime, Inc.:

         The  undersigned  hereby  irrevocably  elects to exercise  the right of
purchase  represented  by the within  Warrant  Certificate  for, and to purchase
thereunder,  _____ shares of Common Stock, as provided for therein,  and tenders
herewith  payment  of the  purchase  price  in  full  in the  form  of cash or a
certified or bank cashier's check in the amount of $_________.

         Please issue a certificate  or  certificates  for such shares of Common
Stock in the name of, and pay any cash for any fractional share to:

PLEASE INSERT SOCIAL SECURITY                 NAME
OR OTHER IDENTIFYING NUMBER                        (Please Print Name &
OF ASSIGNEE                                          Address)


___________________________                   Address

___________________________                   Signature

                                                   NOTE: The   above   signature
                                                         should       correspond
                                                         exactly  with  the name
                                                         on  the  face  of  this
                                                         Warrant  Certificate or
                                                         with  the  name  of the
                                                         assignee  appearing  in
                                                         the   assignment   form
                                                         below.

And, if said number of shares shall not be all the shares  purchasable under the
within  Warrant  Certificate,  a new Warrant  Certificate is to be issued in the
name of said  undersigned  for the balance  remaining  of the share  purchasable
thereunder less any fraction of a share paid in cash.

                                       19

<PAGE>


                                   ASSIGNMENT

          (To be executed only upon assignment of Warrant Certificate)

         For value received,  _____________  hereby sells, assigns and transfers
unto  _______________ the within Warrant  Certificate,  together with all right,
title and interest therein,  and does hereby irrevocably  constitute and appoint
_________________ attorney, to transfer said Warrant Certificate on the books of
the within-named Company, with full power of substitution in the premises.

Dated:___________________                       ________________________________
                                                NOTE: The above signature should
                                                      correspond   exactly  with
                                                      the  name  on the  face of
                                                      this Warrant Certificate.

                                       20