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                                                                    EXHIBIT 10.4

                              HYCOR BIOMEDICAL INC.
                             2001 STOCK OPTION PLAN

      PURPOSE. The Plan is intended to provide incentive to employees,
directors, advisors and consultants of the Corporation, to encourage such
employees to remain in the employ of the Corporation or such directors, advisors
and consultants to remain in the service of the Corporation, and to attract new
employees, directors, advisors and consultants with outstanding qualifications.

      DEFINITIONS. Unless otherwise defined herein or the context otherwise
requires, the capitalized terms used herein shall have the following meanings:

            "Administrator" shall mean the Board or the Plan Committee of the
Board, whichever shall be administering the Plan from time to time in the
discretion of the Board, as described in Section 4 of the Plan.

            "Board" shall mean the Board of Directors of the Corporation.

            "Change of Control" shall mean, a change of control of a nature that
would be required to be reported in response to Item 1 of Form 8-K required to
be filed pursuant to the Exchange Act; provided that, without limitation, such a
Change of Control shall be deemed to have occurred if:

                  the stockholders of the Company approve a definitive agreement
to sell, transfer, or otherwise dispose of all or substantially all of the
Company's assets and properties; or

                  any "person" (as such term is used in Section 13(d) and 14(d)
of the Exchange Act), other than the Company, is or becomes the "beneficial
owner" (as defined in Rule 13d-3 under the Exchange Act), directly or
indirectly, of securities of the Company representing fifty percent (50%) or
more of the combined voting power of the Company's then outstanding securities;
provided, however, that the following shall not constitute a "Change of Control"
of the Company:

                        any acquisition directly from the Company (excluding any
acquisition resulting from the exercise of a conversion or exchange privilege in
respect of outstanding convertible or exchangeable securities); or

                        any acquisition by an employee benefit plan (or related
trust) sponsored or maintained by the Company or any corporation controlled by
the Company; or

                  during any period of two consecutive years during the term of
this Plan, individuals who at the beginning of such period constitute the Board
cease for any reason to constitute at least a majority thereof, unless the
election of each director who was not a director at the beginning of such period
has been approved in advance by directors representing at least two-thirds of
the directors then in office who were directors at the beginning of the period;
or

                  the stockholders of the Company approve the dissolution of the
Company or a definitive agreement to merge or consolidate the Company with or
into another entity in which the Company is not the continuing or surviving
corporation or pursuant to which any shares of the Company's stock would be
converted into cash, securities or other property of another entity, other than
a merger of the Company in which holders of the Company's Common Stock
immediately prior to the merger own, either directly or indirectly, fifty
percent (50%) or more of the equity interests or combined voting power of the
surviving entity or corporation immediately following such merger.

            "Code" shall mean the Internal Revenue Code of 1986, as amended.

            "Commission" shall mean the Securities and Exchange Commission.

            "Common Stock" shall mean the common stock of the Corporation and
any class of shares into which such common stock hereafter may be converted or
reclassified.

            "Corporation" shall mean Hycor Biomedical Inc., a Delaware
corporation.

            "Disability" shall mean a medically determinable physical or mental
impairment which has made an individual incapable of engaging in any substantial
gainful activity. A

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condition shall be considered a Disability only if (i) it can be expected to
result in death or has lasted or it can be expected to last for a continuous
period of not less than twelve (12) months, and (ii) the Administrator, based
upon medical evidence, has expressly determined that Disability exists.

            "Employee" shall mean an individual who is employed (within the
meaning of Section 3401 of the Code and the regulations thereunder) by the
Corporation.

            "Exchange Act" shall mean the Securities Exchange Act of 1934, as
amended.

            "Exercise Price" shall mean the price per Share of Common Stock,
determined by the Administrator, at which an Option may be exercised.

            "Fair Market Value" shall mean the value of one (1) Share of Common
Stock, determined as follows:

                  If the Shares are (A) listed on an exchange, the closing price
as reported for composite transactions on the date of valuation, or, if no sale
occurred on that date, then the mean between the closing bid and asked prices on
such exchange on such date, or (B) traded over-the-counter on the National
Market System (the "NMS") of The Nasdaq Stock Market, Inc. ("NASDAQ"), the last
sale price on the date of valuation, or, if no sale occurred on such date, the
last sale price on the business day immediately prior to the date of valuation,
or, if no sale occurred on that date, then the mean between the highest bid and
lowest asked prices as of the close of business on the business day immediately
prior to the date of valuation, as reported in NASDAQ;

                  If the Shares are not traded on an exchange or the NMS but are
otherwise traded over-the-counter, the mean between the highest bid and lowest
asked prices quoted in NASDAQ as of the close of business on the date of
valuation, or, if on such day such Shares are not quoted in NASDAQ, the mean
between the representative bid and asked prices on such date in the domestic
over-the-counter market as reported by the National Quotation Bureau, Inc., or
any similar successor organization; or

                  If neither clause (i) nor (ii) above applies, the Fair Market
Value shall be determined by the Administrator in good faith. Such determination
shall be conclusive and binding on all persons.

            "Grant Date" shall mean the date on which the granting of an Option
is authorized by the Administrator or such other date as prescribed by the
Administrator.

            "Incentive Stock Option" shall mean an option described in Section
422 of the Code.

            "Nonstatutory Stock Option" shall mean an option that does not meet
the requirements of Section 422 of the Code or is not intended to be an
Incentive Stock Option.

            "Option" shall mean any stock option granted pursuant to the Plan.

            "Option Agreement" shall mean a written stock option agreement
evidencing the grant of an Option.

            "Option Limit" shall have the meaning assigned to it in Section 6.

            "Optionee" shall mean a Participant who has received an Option.

            "Participant" shall have the meaning assigned to it in Section 5(a)
hereof.

            "Plan" shall mean this Hycor Biomedical Inc. 2001 Stock Option Plan,
as it may be amended from time to time.

            "Plan Committee" shall mean a committee of two or more directors
appointed by the Board to administer the Plan.

            "Purchase Price" shall mean the Exercise Price multiplied by the
number of Shares with respect to which an Option is exercised.

            "Retirement" shall mean the voluntary termination of employment by
an employee after qualifying for early or normal retirement under any pension
plan or profit sharing or

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benefit plan of the Corporation or its Subsidiaries. If an employee is not
covered by any such plan, "Retirement" shall mean voluntary termination of
employment after the employee has attained age sixty-five (65) and after the
employee has attained the tenth (10th) anniversary of his or her employment, or
as otherwise determined in the Administrator's sole discretion.

            "Section 16 Participant" shall mean a Participant who is (or, in the
opinion of the Administrator, may be) generally subject to the Section 16
Requirements with respect to purchases and sales of Common Stock or other equity
securities of the Corporation.

            "Section 16 Requirements" shall mean the those obligations and
requirements imposed on officers and directors by Sections 16(a) and 16(b) of
the Exchange Act and the rules of the Commission promulgated thereunder.

            "Securities Act" shall mean the Securities Act of 1933, as amended.

            "Subsidiary" shall mean any subsidiary corporation as defined in
Section 425(f) of the Code.

            "Share" shall mean one share of Common Stock, adjusted in accordance
with Section 10 of the Plan (if applicable).

            "Transfer Agent" shall mean a third-party organization retained by
the Corporation to maintain the stock transfer records of the Corporation.

      EFFECTIVE DATE. The Plan was adopted by the Board effective February 23,
2001. Options granted hereunder prior to obtaining stockholder approval in
accordance with Section 15 of the Plan shall be subject to such approval and
shall be canceled if such approval is not obtained.

      ADMINISTRATION.

            Administrator. Subject to subsection (c) below, the Plan shall be
administered, in the discretion of the Board from time to time, by the Board or
by a Plan Committee which shall be appointed by the Board as provided in the
Corporation's Bylaws. The Board may from time to time remove members from, or
add members to, the Plan Committee. Vacancies on the Plan Committee, however
caused, shall be filled by the Board. The Board shall appoint one of the members
of the Plan Committee as Chairman. The Administrator shall hold meetings at such
times and places as it may determine. Acts of a majority of the Administrator at
which a quorum is present, or acts reduced to or approved in writing by the
unanimous consent of the members of the Administrator, shall be the valid acts
of the Administrator.

            Powers of Administrator. The Administrator shall from time to time
at its discretion select the Optionees who are to be granted Options, determine
the number of Shares to be subject to Options to be granted to each Optionee and
designate such Options as Incentive Stock Options or Nonstatutory Stock Options.
The Administrator shall have full power and authority to operate, manage and
administer the Plan and interpret and construe the Plan and the terms of all
Option Agreements. The interpretation and construction by the Administrator of
any provision of the Plan or of any Option or Option Agreement shall be final.
No member of the Administrator shall be liable for any action or determination
made in good faith with respect to the Plan or any Option.

            Disinterested Administration. If the Common Stock is registered
under the Exchange Act and Section 16 Participants are to receive Options
hereunder, this Plan shall be administered by the Board or by a Plan Committee
consisting solely of two or more directors each of whom shall be a "non-employee
director" within the meaning of Rule 16b-3(b)(3) of the Exchange Act and an
"outside director" within the meaning of Section 162(m) of the Code.

      PARTICIPATION.

            Eligibility. The Optionee shall be such persons (collectively,
"Participants"; individually a "Participant") as the Administrator may select
from among the following classes of persons, subject to the terms and conditions
of Section 5(b) below:

                  Employees (who may be officers, whether or not they are
directors) of the Corporation or of a Subsidiary and non-employees to whom an
offer of employment has been extended; and

                  directors, advisors and consultants of the Corporation or a
Subsidiary.

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      Notwithstanding provisions of the first paragraph of this Section 5(a),
the Administrator may at any time or from time to time designate one or more
directors as being ineligible for selection as Participants in the Plan for any
period or periods of time. The Administrator may, in its sole discretion and
upon such terms as it deems appropriate, require as a condition of the grant of
an Option to a Participant that the Participant surrender for cancellation some
or all of the Options which have been previously granted to such person under
this Plan or otherwise. An Option, the grant of which is conditioned upon such
surrender, may have an option price lower (or higher) than the exercise price of
such surrendered Option, may cover the same (or a lesser or greater) number of
shares as such surrendered Option, may contain such other terms as the
Administrator deems appropriate, and shall be exerciseable in accordance with
its terms, without regard to the number of shares, price, exercise period or any
other term or condition of such surrendered Option.

            Ten-Percent Stockholders. A Participant who, at the time of grant,
owns more than ten percent (10%) of the total combined voting power of all
classes of outstanding stock of the Corporation or its parent shall not be
eligible to receive an Incentive Stock Option unless the Exercise Price of the
Shares subject to such Option is at least one hundred ten percent (110%) of the
Fair Market Value of such Shares on the Grant Date.

            Stock Ownership. For purposes of Section 5(b) above, in determining
stock ownership, a Participant shall be considered as owning the stock owned,
directly or indirectly, by or for his or her brothers and sisters, spouse,
ancestors and lineal descendants. Stock owned, directly or indirectly, by or for
a corporation, partnership, estate or trust shall be considered as being owned
proportionately by or for its stockholders, partners or beneficiaries. Stock
with respect to which such Participant holds an Option shall not be counted.

            Outstanding Stock. For purposes of Section 5(b) above, "outstanding
stock" shall include all stock actually issued and outstanding immediately after
the grant of the Option to the Optionee. "Outstanding stock" shall not include
Shares authorized for issue under outstanding Options held by the Optionee or by
any other person.

      STOCK. The stock subject to Options granted under the Plan shall be Shares
of the Corporation's authorized but unissued or reacquired Common Stock. The
aggregate number of Shares which may be issued upon exercise of Options under
the Plan at any time shall not exceed 1,000,000 Shares (the "Option Limit"),
subject to adjustment as provided for in this Plan. Notwithstanding the
foregoing, upon the full or partial payment of any Purchase Price by the
transfer to the Corporation of Shares or upon satisfaction of tax withholding
provisions in connection with any such exercise or any other payment made or
benefit realized under this Plan by the transfer or relinquishment of Shares,
there shall be deemed to have been issued or transferred under this Plan only
the net number of Shares actually issued or transferred by the Corporation. In
the event any outstanding Option granted under this Plan for any reason expires
or is canceled or terminated, the Shares allocable to the unexercised portion of
such Option shall again be available to be granted as Options under this Plan.
Notwithstanding the previous sentence, to the extent required by Section 162(m)
of the Code, Shares subject to Options which are canceled continue to be counted
against the Option Limit and if, after an Option grant, the price of Shares
subject to such Option is reduced, the transaction is treated as a cancellation
of the Option and a grant of a New Option and both the Option deemed to be
canceled and the Option deemed to be granted are counted against the Option
Limit. The limitations established by this Section 6 shall be subject to
adjustment in the manner provided in Section 10 hereof upon the occurrence of an
event specified in Section 10.

      TERMS AND CONDITIONS OF OPTIONS.

            Stock Option Agreements. Each Option shall be evidenced by an Option
Agreement in such other form as the Administrator shall from time to time
determine. Such Option Agreements need not be identical but shall comply with
and be subject to the terms and conditions set forth in this Section 7.

            Nature of Option. Each Option shall state whether it is an Incentive
Stock Option or a Nonstatutory Stock Option.

            Optionee's Undertaking. Each Optionee shall agree to remain in the
employ or service of the Corporation and to render services for a period as
shall be determined by the Administrator, from the Grant Date of the Option or
such other date agreed to by the Optionee and the Corporation, but such
agreement shall not impose upon the Corporation any obligation to retain the
Optionee in their employ or service for any period.

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            Number of Shares. Each Option shall state the number of Shares to
which it pertains and shall provide for the adjustment thereof in accordance
with the provisions of Section 10 hereof.

            Exercise Price; Exercise of Options. Each Option shall state the
Exercise Price. The Exercise Price in the case of an Incentive Stock Option
granted to an Optionee described in Section 5(b) hereof, shall not be less than
one hundred ten percent (110%) of the Fair Market Value on the Grant Date. The
Exercise Price in the case of any Incentive Stock Option granted to persons
other than to an Optionee described in Section 5(b) hereof, shall not be less
than the Fair Market Value on the Grant Date. The Exercise Price in the case of
any Nonstatutory Stock Option, shall not be less than Eighty-five percent (85%)
of the Fair Market Value on the Grant Date. At the sole discretion of the
Administrator, any Option granted under this Plan to any Participant may be
exercisable in whole or in part immediately upon the grant thereof, or only
after the occurrence of a specified event and/or only in installments, which
installments may be equal or otherwise, and which installments may vary as to
the number thereof as well as to whether any unexercised installments are
cumulative through the life of a particular Option.

            Medium and Time of Payment; Notice. The Purchase Price shall be
payable in full in United States dollars upon the exercise of the Option;
provided, however, that if the applicable Option Agreement so provides, or the
Administrator in its sole discretion otherwise approves thereof, the Purchase
Price may (to the extent permitted by applicable law) be paid by the surrender
of Shares in good form for transfer, owned by the person exercising the Option
and having a Fair Market Value on the date of exercise equal to the Purchase
Price.

      In the event the Corporation determines that it is required to withhold
state or Federal income tax as a result of the exercise of an Option, as a
condition to the exercise thereof, an Optionee must make arrangements
satisfactory to the Corporation to enable it to satisfy such withholding
requirements before the Optionee shall be permitted to exercise the Option.
Payment of such withholding requirements may be made, in the discretion of the
Administrator, (i) in cash, (ii) by delivery of Shares registered in the name of
the Optionee, or by the Corporation not issuing such number of Shares subject to
the Option, having a Fair Market Value at the time of exercise equal to the
amount to be withheld or (iii) any combination of (i) and (ii) above.

      The Optionee shall exercise an Option by completing and delivering to the
Corporation, concurrently with the payment of the Purchase Price in the manner
described above, an exercise notice in such form as the Administrator shall from
time to time determine.

            Term and Non-Transferability of Options. Each Option shall state the
time or times when all or part thereof becomes exercisable. No Option shall be
exercisable after the expiration of ten (10) years (or less, in the discretion
of the Administrator) from the Grant Date; except that no Incentive Stock Option
granted to an Optionee described in Section 5(b) hereof shall be exercisable
after the expiration of five (5) years from the Grant Date (or less, in the
discretion of the Administrator). During the lifetime of the Optionee, the
Option shall be exercisable only by the Optionee or the Optionee's guardian or
legal representative and shall not be assignable or transferable. The Option
shall not be transferable by the Optionee other than by will or the laws of
descent and distribution. Any other attempted alienation, assignment, pledge,
hypothecation, attachment, execution or similar process, whether voluntary or
involuntary, with respect to all or any part of any Option or right thereunder,
shall be null and void and, at the Corporation's option, shall cause all of the
Optionee's rights under the Option to terminate.

            Cessation of Employment (Except by Death, Disability or Retirement).
If an Optionee's employment or service with the Corporation ceases for any
reason or no reason, whether voluntarily or involuntarily, with or without
cause, other than pursuant to death, Disability or Retirement, such Optionee
shall have the right, subject to the restrictions referred to in Section 7(g)
above, to exercise the Option at any time within ninety (90) days after such
cessation, but, except as otherwise provided in the applicable Option Agreement,
only to the extent that, at the date of such cessation, the Optionee's right to
exercise such Option had accrued pursuant to the terms of the applicable Option
Agreement and had not previously been exercised.

      For purposes of this Section 7(h), the employment relationship shall be
treated as continuing intact while the Optionee is on military leave, sick leave
or other bona fide leave of absence (to be determined in the sole discretion of
the Administrator). The foregoing notwithstanding, in the case of an Incentive
Stock Option, employment shall not be deemed to continue beyond the ninetieth
(90th) day after the Optionee ceased active employment, unless the Optionee's
reemployment rights are guaranteed by statute or by contract.

            Death of Optionee. If an Optionee's employment or service with the
Corporation

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ceases by reason of the Optionee's death, or after ceasing to be a Participant
but during the period in which he or she could have exercised the Option under
this Section 7, and has not fully exercised the Option, then the Option may be
exercised in full, subject to the restrictions referred to in Section 7(g)
above, at any time within twelve (12) months after the Optionee's death by the
executor or administrator of his or her estate or by any person or persons who
have acquired the Option directly from the Optionee by bequest or inheritance,
but, except as otherwise provided in the applicable Option Agreement, only to
the extent that, at the date of death, the Optionee's right to exercise such
Option had accrued and had not been forfeited pursuant to the terms of the
applicable Option Agreement and had not previously been exercised.

            Disability of Optionee. If an Optionee's employment or service with
the Corporation ceases by reason of the Optionee's Disability, such Optionee
shall have the right, subject to the restrictions referred to in Section 7(g)
above, to exercise the Option at any time within twelve (12) months after such
cessation by reason of Disability, but, except as provided in the applicable
Option Agreement, only to the extent that, at the date of such cessation, the
Optionee's right to exercise such Option had accrued pursuant to the terms of
the applicable Option Agreement and had not previously been exercised.

            Retirement of Optionee. If an Optionee's employment or service with
the Corporation ceases by reason of the Optionee's Retirement, such Optionee
shall have the right, subject to the restrictions referred to in Section 7(g)
above, to exercise the Option at any time within six (6) months days after the
date of Retirement, but only to the extent that, at the date of such cessation,
the Optionee's right to exercise such Option had accrued pursuant to the terms
of the applicable Option Agreement and had not previously been exercised.

            Time of Cessation of Service. For purposes of this Plan, the
Optionee's employment or service shall be deemed to have ceased or be terminated
on the date when the Optionee's employment or service in fact ceased or Optionee
is in fact terminated.

            Rights as a Stockholder. No one shall have rights as a stockholder
with respect to any Shares covered by an Option until the date of the issuance
of a stock certificate for such Shares. No adjustment shall be made for
dividends (ordinary or extraordinary, whether in cash, securities or other
property), distributions or other rights for which the record date is prior to
the date such stock certificate is issued, except as expressly provided in
Section 10 hereof.

            Modification, Extension and Renewal of Options. Within the
limitations of the Plan, the Administrator may modify an Option, extend or renew
outstanding Options or accept the cancellation of outstanding Options (to the
extent not previously exercised) for the granting of new Options in substitution
therefor. The foregoing notwithstanding, no modification of an Option shall,
without the consent of the Optionee, adversely alter or impair any rights or
obligations under any Option previously granted. With the consent of the
affected Optionee, the Administrator may cancel any agreement evidencing
Options. In the event of such cancellation, the Administrator may authorize the
granting of new Options, which may or may not cover the same number of Shares
that have been the subject of the prior award, at such Exercise Price and
subject to such terms, conditions and discretions as would have been applicable
under this Plan had the canceled Options not been granted.

            Substitution of Options. Notwithstanding any inconsistent provisions
or limits under the Plan, in the event the Corporation acquires (whether by
purchase, merger or otherwise) all or substantially all of outstanding capital
stock or assets of another corporation or of any reorganization or other
transaction qualifying under Section 424 of the Code, the Administrator may, in
accordance with the provisions of that Section, substitute Options under the
Plan for options under the plan of the acquired company; provided, however, that
(i) the excess of the aggregate fair market value of the shares subject to an
option immediately after the substitution over the aggregate option price of
such shares is not more than the similar excess immediately before such
substitution and (ii) the new option does not give persons additional benefits,
including any extension of the exercise period.

            Other Provisions. An Option Agreement authorized under the Plan may
contain such terms and provisions not inconsistent with the terms of the Plan
(including, without limitation, restrictions upon the exercise of the Option) as
the Administrator shall deem advisable in its sole and absolute discretion.

      LIMITATION ON INCENTIVE STOCK OPTIONS. To the extent that the aggregate
Fair Market Value (determined as of the Grant Date) of the Shares with respect
to which Incentive Stock Options are exercisable for the first time by any
Optionee during any calendar year under the

<PAGE>

Plan and all other plans maintained by the Corporation or its parent, exceeds
$100,000, such excess Options shall be treated as Nonstatutory Stock Options.
For the purposes of this Section 8, Incentive Stock Options shall be taken into
account in the order in which they were granted.

      TERM OF PLAN. Options may be granted pursuant to the Plan until the
expiration of the Plan ten (10) years after the effective date referred to in
Section 3.

      EFFECT OF CERTAIN EVENTS.

            Adjustments Upon Changes in Stock. The Administrator shall make or
provide for such adjustments in the Option Limit, the Exercise Price and in the
number or kind of shares or other securities (including shares or other
securities of another issuer) covered by this Plan and outstanding Options as
the Administrator in its sole discretion, exercised in good faith, shall
determine is equitably required to prevent dilution or enlargement of rights of
optionees that would otherwise result from (a) any stock dividend, stock split,
combination of shares, issuance of rights or warrants to purchase stock,
spin-off, recapitalization or other changes in the capital structure of the
Corporation, (b) any merger, consolidation, reorganization or partial or
complete liquidations, or (c) any other corporate transaction or event having an
effect similar to any of the foregoing. The Administrator may also make or
provide for such adjustment in the number or kind of shares of the Corporation's
capital stock or other securities (or in shares or other securities of another
issuer) which may be acquired pursuant to Options granted under the Plan and the
number of such securities to be awarded to each Optionee as the Administrator in
its sole discretion, shall determine is appropriate to reflect any transaction
or event described in the preceding sentence. In the event of any such
transaction or event, the Administrator may provide in substitution for any or
all outstanding Options under the Plan such alternative consideration (including
securities of any surviving entity) as it may in good faith determine to be
equitable under the circumstances and may require in connection therewith the
surrender of all Options so replaced. In any case, such substitution of
securities shall not require the consent of any person who is granted Options
pursuant to the Plan. The determination of the Administrator as to what
adjustments shall be made, and the extent thereof, shall be final, binding and
conclusive.

            Change of Control. In addition to the rights set forth in Section
10(a) above, in the event of a Change of Control, the Administrator may, in its
sole discretion, without obtaining stockholder approval or the consent of any
person granted Options under the Plan, take one or more of the following
actions:

                  Accelerate the exercise dates of any outstanding Options, or
make Options fully vested and exercisable;

                  Pay cash to any or all owners of Options in exchange for the
cancellation of their outstanding Options; or

                  Make any other adjustments or amendments to the Plan and
outstanding Options and substitute new Options for outstanding Options.

            Adjustment Determination. To the extent that the foregoing
adjustments relate to securities of the Corporation, such adjustments shall be
made by the Administrator, whose determination shall be conclusive and binding
on all persons.

            Limitation on Rights. Except as expressly provided in this Section
10, the Optionee shall have no rights by reason of any subdivision or
consolidation of shares of stock of any class, the payment of any stock dividend
or any other increase or decrease in the number of shares of stock of any class
or by reason of any dissolution, liquidation, merger or consolidation or spinoff
of assets or stock of another corporation, and any issue by the Corporation of
shares of stock of any class, or securities convertible into shares of stock of
any class, shall not affect, and no adjustment by reason thereof shall be made
with respect to, the number or Exercise Price of Shares subject to an Option.
The grant of an Option pursuant to the Plan shall not affect in any way the
right or power of the Corporation to make adjustments, reclassifications,
reorganizations or changes of its capital or business structure, to merge or
consolidate or to dissolve, liquidate, sell or transfer all or any part of its
business or assets.

      SECURITIES LAW REQUIREMENTS.

            Legality of Issuance. No Shares shall be issued upon the exercise of
any Option unless and until the Corporation has determined that:

<PAGE>

                  it and the Optionee have taken all actions required to
register the offer and sale of the Shares under the Securities Act, or to
perfect an exemption from the registration requirements thereof;

                  any applicable listing requirement of any stock exchange on
which the Common Stock is listed has been satisfied; and

                  any other applicable provision of state or Federal law has
been satisfied.

            Restrictions on Transfer; Representations of Optionee; Legends.
Regardless of whether the offering and sale of Shares under the Plan has been
registered under the Securities Act or has been registered or qualified under
the securities laws of any state, the Corporation may impose restrictions upon
the sale, pledge or other transfer of such Shares (including the placement of
appropriate legends on stock certificates) if, in the judgment of the
Corporation and its counsel, such restrictions are necessary or desirable in
order to achieve compliance with the provisions of the Securities Act, the
securities laws of any state or any other law. In the event that the sale of
Shares under the Plan is not registered under the Securities Act but an
exemption is available which requires an investment representation or other
representation, each Optionee shall be required to represent that such Shares
are being acquired for investment, and not with a view to the sale or
distribution thereof, and to make such other representations as are deemed
necessary or appropriate by the Corporation and its counsel. Stock certificates
evidencing Shares acquired under the Plan pursuant to an unregistered
transaction shall bear the following restrictive legend and such other
restrictive legends as are required or deemed advisable under the provisions of
any applicable law:

            "THE SALE OF THE SECURITIES REPRESENTED HEREBY HAS NOT BEEN
REGISTERED UNDER THE SECURITIES ACT OF 1933 AS AMENDED (THE "ACT"). ANY TRANSFER
OR PLEDGE OF SUCH SECURITIES WILL BE INVALID UNLESS A REGISTRATION STATEMENT
UNDER THE ACT IS IN EFFECT AS TO SUCH TRANSFER OR IN THE OPINION OF COUNSEL FOR
THE ISSUER SUCH REGISTRATION IS UNNECESSARY IN ORDER FOR SUCH TRANSFER OR PLEDGE
TO COMPLY WITH THE ACT."

      Any determination by the Corporation and its counsel in connection with
any of the matters set forth in this Section 11 shall be conclusive and binding
on all persons.

            Registration or Qualification of Securities. The Corporation may,
but shall not be obligated to, register or qualify the sale of Shares under the
Securities Act or any other applicable law. The Corporation shall not be
obligated to take any affirmative action in order to cause the sale of Shares
under the Plan to comply with any law.

            Exchange of Certificates. If, in the opinion of the Corporation and
its counsel, any legend placed on a stock certificate representing Shares sold
under the Plan is no longer required, the holder of such certificate shall be
entitled to exchange such certificate for a certificate representing the same
number of Shares but without such legend.

      AMENDMENT OF THE PLAN. The Administrator may from time to time, with
respect to any Shares at the time not subject to Options, suspend or discontinue
the Plan or revise or amend it in any respect whatsoever except that, without
the approval of the Corporation's stockholders, no such revision or amendment
shall:

            Be made if stockholder approval is required by applicable law,
regulation or the requirements of The Nasdaq Stock Market or any exchange or
interdealer network where the Shares are trading;

            Increase the number of Shares which may be issued under the Plan;
            Amend this Section 12 to defeat its purpose.

      Without limiting the generality of the foregoing, the Administrator may
amend this Plan to eliminate provisions which are no longer necessary as a
result of changes in tax or securities laws or regulations, or in the
interpretation thereof.

      FINANCIAL STATEMENTS. Each Optionee shall receive financial statements of
the Corporation not less than annually.

      APPLICATION OF FUNDS. The proceeds received by the Corporation from the
sale of Common Stock pursuant to the exercise of an Option will be used for
general corporate purposes.

      APPROVAL OF STOCKHOLDERS. The Plan must be approved by the affirmative
vote of the

<PAGE>

holders of a majority of the Corporation's outstanding shares of capital stock
on or before the date twelve (12) months from the date the Plan was adopted by
the Board.

      GOVERNING LAW. This Plan, and the Option Agreements, shall be governed by
and enforced and construed in accordance with the internal substantive laws (and
not the laws of conflicts of laws) of the State of California.

      To record the adoption of the Plan by the Board as of February 23, 2001,
the Board has caused its authorized officers to sign the Plan and affix the
corporate seal hereto.

HYCOR BIOMEDICAL INC.

By:
Name:   /s/ J. David Tholen
       ---------------------
Title: President

By:
Name:  /s/ Reginald P. Jones
       ----------------------
Title: Secretary