NOTE: Attempt FIVE questions in all, including question No. 8 which is COMPULSORY. All questions carry EQUAL marks.

1. (a) Draw neat diagram representing important stages of meiosis in an organism having the diploid chromosomal number of 4. (12)
(b) Define Excretion and briefly discuss the main excretory products in animals. (8)

2. (a) Define and explain Generic Linkage. What are the cytogical bases of linkage? (8)
(b) How will you explain the production of long neck in Giraffe under Darwinian Theory. (12)

3. (a) Give a detailed account of Phosphorous cycle. (10)
(b) What do you understand from energy subsidy? (5)
(c) Define hormones. How do these differ from enzymes? (5)

4. (a) Discuss the mechanism of transport of oxygen from lungs to the tissues. (10)
(b) Write a brief note on Paracentric Inversion. (10)

5. (a) Give a brief account of Orthogenesis. (8)
(b) Discuss the basic structure and chemical composition of Mitochondrion. (12)

6. (a) Define pollution. Discuss air pollution with reference to Pakistan. (8)
(b) Define and explain Epistasis. How does it differ from Genetic dominance? (12)

7. Write short notes on the following:
(a) Golgi Complex
(b) Global warming
(c) Possible first living organism
(d) Linkage



8. Write only the correct answer in the Answer Book. Do not reproduce the questions.


(1) The main division of the chromosomes occurs in:
(a) Prophase
(b) Metaphase
(c) Anaphase
(d) Jelophase
(e) None of these

(2) The protein synthesis occurs in:
(a) Mitochondria
(b) Endoplasmic reticulum
(c) Ribosomes
(d) Acrosome
(e) None of these

(3) Blood antigens are present in:
(a) Blood serum
(b) RBC’s
(c) WBC’s
(d) Platelets
(e) None of these

(4) Sex linked genes are the genes located on:
(a) X-chromosome only
(b) Y-chromosome only
(c) Both X and Y-chromosomes
(d) X or Y-chromosomes
(e) None of these

(5) Transcription is the phenomenon associated with:
(a) Synthesis of new DNA
(b) Formation of mRNA and DNA
(c) Formation of tRNA
(d) None of these

(6) Segregation of alleles of a gene occurs in:
(a) Diploid individual
(b) Homozygous individual
(c) Heterozygous individual
(d) All of the above
(e) None of these

(7) Sodium-Potassium pump is located in:
(a) Liver
(b) Heart Cell
(c) Nerve cell
(d) All of the above
(e) None of these

(8) Pepsin is an enzyme responsible for breaking:
(a) Proteins
(b) Lipids
(c) Fats
(d) None of these

(9) Pace maker is located in:
(a) Liver
(b) Brain
(c) Heart
(d) Muscle
(e) None of these

(10) Follicle stimulating hormones are produced in:
(a) Pituitary
(b) Ovaries
(c) Thyroid
(d) Kidney
(e) None of these

(11) Genetic dominance is strongly associated with:
(a) Personality dominance
(b) Adaptive value
(c) Population distribution
(d) None of these

(12) Crossing over is the physical exchange between chromosomes.
(a) Homologous
(b) Non-Homologous
(c) Both (a) and (b)
(d) None of these

(13) XXY individual in man is phonotypically a
(a) Male
(b) Female
(c) Inter sex
(d) None of these

(14) Amino acids are the organic compound behaving like:
(a) Acid
(b) Base
(c) Both (a) and (b)
(d) None of these

(15) Which of these can be the first living organism on the earth:
(a) Protozoan
(b) Algae
(c) Virus
(d) None of these

(16) Ontogeny represents the history of an organism.
(a) Revolutionary
(b) Embryonic
(c) Both (a) and (b)
(d) None of these

(17) Nuclear membrane has a structure similar to:
(a) Cell membrane
(b) Mitochondrion
(c) Endoplasmic reticulum
(d) All of these

(18) Osmosis is the movement of solutes through a membrane.
(a) Permeable
(b) Semi-permeable
(c) Both (a) and (b)
(d) None of these

(19) Sickle Cell Anemia is the condition where the RBS’s deflate.
(a) Under Oxygen
(b) Absence of Oxygen
(c) Both (a) and (b)
(d) None of these

(20) Pond is an example of ecosystem:
(a) Complete
(b) Incomplete
(c) Almost complete
(d) None of these

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