16.Fertilization: The process of fusion of male and female gametes 17.Parthenogenesis: The development of egg to new form without fertilization. E.g Rotifers, Honey bees, Turkey birds etc. 18.External fertilization: When fertilization takes place outside the body of organisms. E.g Frog and Bony Fishes. 19.Internal Fertilization: When fertilization takes place inside the body of female organisms. E.g Female human. 20.Zygote: The product of fusion of male and female gametes. 21.Embryogenesis: The development of embryo from the zygote. 22.Oviparous: Egg laying animals e.g Fishes, Reptiles, Amphibians and Birds. 23.Viviparous: The organism which gives birth of young one. E.g Mammals excepting Echidra ( oviparous mammals) 24.Pericarp: Protective wall of fruit, sometimes pericarp is differentiated into mesocarp and Endocarp. 25.Clone: Organisms which are morphologically and Genetically identical with eah other. B. Important Notes: 1.Life Span Period from birth till natural death.Every organism lives only for certain period of time Eg Elephant 60 -90 years, Fruit fly 4-5 weeks. Life span of mayfly is one day.Life span of Man is 100 years.Life span of parrot is 140 years Life span of a banyan tree is 200 yearsLife span of Tortoises is 100- 150 years PHASES OF LIFE SPAN. Juvenile phase: The phase of growth before reproductive maturity. Reproductive phase: Reproductive maturity. Senescent phase: Phase between reproductive maturity and death. 2.Reproduction: The biological process by which an organism produces its own kind to maintain the race. Reproduction enables the continuity of species generation after generation. Types of Reproduction: Asexual reproduction
antigens autoimmunity Autoimmunity is the failure of an organism to recognize its own constituent parts as self, which allows an immune response against its own cells and tissues. Benign tumor It is tumor that lacks all three of the malignant properties of a cancer. A benign tumor does not invade surrounding tissues and does not metastatise. Contact inhibition It is a natural process of arresting cell growth when two or more cells come into contact with each other. Innate immunity The innate immunity comprises of cells and mechanisms that defend the host in a manner interferon Thes are proteins made and released by the cells of most vertebrates in response to the presence of pathogens or tumor cells. They allow communication between cells to trigger the protective defences of the immune system that eradicate pathogens. Malignant tumor A group of cells which display uncontrolled growth , invasion and sometimes metastasis. Oncogenic virus An oncovirus is a virus that can cause cancer Passive immunity The immunity that is developed due to the transfer of ready made antibodies. Withdrawl syndrome A group of symptoms that occurs upon the abrupt discontinuation of dosage of drug or alcohol. ONE MARK QUESTIONS 1. Name the diagnostic test which confirms typhoid. 2. Name the two major groups of cells required to attain specific immunity. 3. Infectious diseases are more common than non-infectious diseases. Give reasoS 4. Do you agree with the statement that Auto-immunity causes some diseases? If so, name the diseases. 5. Breast fed babies are more immune to diseases than the bottle fed babies. Why? ANSWERS Widal test B-lymphocytes and T-lymphocytes.
Features of cloning vector: Origin of replication (Ori), selectable marker and cloning sites are the features that are required to facilitate cloning into a vector. Origin of Replication (Ori) : This is a sequence from where replication starts and any piece of DNA when linked to this sequence can be made to replicate within the host cells. This sequence is also responsible for controlling the copy number of the linked DNA. Selectable Marker : It is a gene which helps in identifying and eliminating from transformants (having recombinant DNA) by selectively permitting the growth of transformants. The process through which a piece of DNA is introduced in a host bacterium is called transformation. The genes encooling resistance to antibiotics are considered useful selectable marker for E.coli
Presence of single defective X chromosome results in disorder. Women can develop this disorder if both the defective copies of X chromosome, which is rare. 29 Diagram NCERT text book Fig 2.79d) and correct labeling Functional megaspore mother cell Detailed explanation Egg cell--- forms zygote & future embryo Polar nuclei--- form PEN and provide nourishment to the embryo Antipodals--- degenerate OR Ref. NCERT text book fig 3.11 Fallopian tube, zygote undergoes change to form blastomeres and develop 8-16 cell stage the morula, then blastocyst- implantation ½ x3=1.5 ½ 1.5 ½ ½ ½ 4+1=5 30 I will deny in having drink in an assertive way to maintain the friendship. Any 2 harmful effects; Affects nervous system Peptic ulcer Hepatitis Prevention and control Avoid undue peer pressure Seeking help from parents/ (any other correct two points) 1 1 x 2=2 1 x 2=2 BIOLOGY (Theory) CLASS –XII Blue Print Class (XII) S.NO. Type of question → Units↓ VSA (1 mark) SA-II (2 marks) SA-I (3 marks) LA (5 marks) Total 1 Sexual reproduction 2 (2) 4(2) 6(2) - 12(6) 2 Genetics & Evolution 2(2) 4(2) 9(3) 5(1) 20(8)
Ascariasis Ascaris Through contaminated water, vegetables and fruits d 13. In which part of the body of the hosts do the following events in the life cycles of Plasmodium takes place (Name body part and host both) (a) Fertilization (b) Development of gametocytes (c) Release of sporozoites (d) Asexual reproduction 2 14. A person injured in a road accident and requiring an urgent immune response was brought to a doctor. 2 (a) What did the doctor immediately do? (b) What kind of immunity was he providing to the patient? 15. Why does a beekeeper keep beehives in crop fields during flowering season? 2. 16. List any four advantages of genetically modified crop plants over their Wild/domesticated relatives. 2 17. As the sewage is discharged in the water body, there is a sharp decline in DO but exponential increase in BOD as depicted in the graph. Study the graph carefully and fill in the gaps A-D. 2
9. 10. 11. 12. 13. 14. 15. 16. 17. Restriction enzymes /Endonucleases or Exonucleases) SECTION-B (I) Only one pollen tube enters an ovule so 10 pollen tubes will be required for 10 ovules. (ii) Out of two male gametes per pollen tube, one is used in syngamy and other gamete in triple fusion. (a) Rr (b) None of the parental allele for colour is dominant or recessive showing incomplete dominance. Single Polynucleotide chain a- transmitted through house flies from faeces of infected persons to water,food and food products and thereby by contaminating them b- Ringworm c- Rhinovirus d- Internal bleeding/anaemia/muscular pain (any one) (a) Intestine of mosquito (b) RBCs of human (c) Salivary gland of mosquito (d)Liver cell/ RBCs of human (a) Inject antitoxin/tetanus injection (b) Passive immunity (a) Bees are pollinators of crop plant (b) Provide better yield of honey for bees. (a) More tolerant to abiotic stress (b) Provide better yields of crop (c) Reduced post harvest losses (d) Increased nutritional value of food. (a)kills fish (b) disappearance of clean water(c)reappearance of clean water (d) reappearance of clean water (i) (a) N2O (b) CFCs (ii) Green house gases cause global warming which in turn causes melting of ice caps. 1+1=2 1+1=2 1+1 ½x4 ½x4 1+1 1+1 ½x4 1+1
24. 25. 26. Diagram and Explanation of three steps. Paster’s Two Flask experiment Two flasks used were pre-sterilised Pre-killed yeast placed in both of them One flask was open to air while the other was covered. Flask open to air had new life but not the other one. Life comes from the pre-existing life. a). GGAA and ggaa b).GgAa c). 9:3:3:1 Male gamete + egg (n) (n) 2(n) Male gamete + 2 polar nuclei PEN (triple fusion) (n) (n) (3n) Section D a). b). As endosperm stores and supplies nutrients for developing embryo. c). Wheat – Monocot Castor – Dicot. OR a). At puberty ; in seminiferous tubules of testis b). 1½+1½ 1+1+1 1½+1½ 2+1 1+1+1 ½x6=3
27. 28. c). a). Step wise description with diagram b). It conclusively proved that the genetic material was DNA OR a). Repressor mRNA produces repressor, inducer binds with repressor ; makes repressor inactive ; operator gene becomes active; structural genes z,y,a transcribe mRNA ; LAC – mRNA translates z, y,a genes to give enzymes β- galactosidase , permease and transacetylase. b). Lactose acts as inducer. OR (a). and (b). c). Because resources are pre-stable so carrying capacity controls the population causing the growth curve to be flatter at the end. d) . 1½+1½ 1½+1½ 1 ½+½ 1