NAVJYOTI CONVENT SR.SEC.

SCHOOL,
Radhakishanpura, Sikar (Raj.)
PREBOARD-IV (2024-25)
Subject – Biology
Time : 3.15 Hrs Class – XII M.M. : 56

(Section-A)
Q.1 (i) Pollen grain is a:- / (½)
(a) Microspore/ (b) Megaspore /
(c) Microsporangium / (d) Microsporophyll/
(ii) How many sperms/spermatozoa are produced from one primary
spermatocyte: (½)

(a) 6 (b) 4 (c) 2 (d) 8

(iii) At what stage of life is oogenesis initiated in a human female:- (½)

(a) At puberty /
(b) At menarche /
(c) At menopause /
(d) During embryonic development /
(iv) Which of the following is a method to control birth rate:-
(½)

(a) IUD (b) GIFT (c) ZIFT (d) AI

(v) A diploid organism is heterozygous for 2 loci, how many types of gametes
can be produced:- (½)

(a) 4 (b) 8 (c) 16 (d) 32

(vi) What can be the blood group of the offspring when both parents have AB
blood group:- (½)
𝐴𝐵
(a) AB (b) A, B & AB (c) A, B, AB & O (d) A & B
(vii) Who proposed operon concept:- (½)

(a) Jacob & Monod/ (b) Watson & Crick /

(c) Alec Jeffery’s / (d) Har Govind Khorana /
(viii) According to Hugo de varies, speciation is due to:- (½)

(a) Due to small variations /

(b) Due to natural selection /
(c) Due to reproduction /
(d) Saltation /
(ix) The pathogen of Elephantiasis is:-/ (½)
(a) Amoeba / (b) Ascaris /
(c) Filarial worn / (d) Plasmodium /
(x) The antibody, which cross the placenta is:- (½)

(a) IgA (b) IgD (c) IgE (d) IgG

 (xi) Which of the following microbe is made up of protein only:- (½)

(a) Virus/ (b) Prions/

(c) Viroid’s / (d) Bacteria/
(xii) Genetic information is transferred from nucleus to cytoplasm through:- (½)

(a) DNA / DNA (b) Anticodon /

(c) RNA / RNA (d) All of the above /
(xiii) Which organism is used to transfer T-DNA:- (½)
𝑇 − 𝐷𝑁𝐴
(a) Streptomyces /
(b) Agrobacterium tumifaciens /
(c) Salmonella typhi /
(d) Bacillus thuringinesis /
(xiv) Which step of the PCR are catalyzed by the Taq polymerase enzyme:- (½)
𝑃𝐶𝑅
(a) Denaturation / (b) Anneling /
(c) Extension / (d) All of the above /
(xv) Amensalism can be represented as:- / (½)
(a) Species A (−), specis B (0) / 𝐴(−), 𝐵(0)
(b) Species A (+), Species B (−) / 𝐴(+), 𝐵(−)
(c) Species A (−), Species B (−) / 𝐴(−), 𝐵(−)
(d) Species A (+), Species B (0) / 𝐴(+), 𝐵(0)
(xvi) The most stable ecosystem is:- / (½)
(a) Forest / (b) Desert /
(c) Mountain / (d) Ocean /
(xvii) Kanha national park is famous for:- (½)

(a) Birds / (b) Rhinoceros /

(c) Tiger / (d) Crocodiles /
(xviii) The primary treatment of sewage involver:- (½)

(a) Digestion /
(b) Decomposition /
(c) Sedimentation & Filtration /
(d) Biological treatment /
Q.2 Fill in the blanks:- (i to x) / 𝒊 𝒙
(i) The process of formation of seed without fertilization is called as _________. (½)

(ii) The human primary spermatocyte have _________ chromosome. (½)

(iii) HIV mainly infects the __________. (½)

HIV
(iv) The pathogen of common cold is __________. (½)

(v) _________ is used for production of citric acid in industries. (½)

(vi) The DNA polymerase used in PCR is obtained from __________. (½)
DNA 𝑃𝐶𝑅
 (vii) In insulin chain A & chain B are linked together by __________ bond. (½)
𝐴 𝐵
(viii) __________ was the first transgenic crop. (½)

(ix) The _________ growth shows sigmoid growth curve. (½)

(x) An _________ is a functional unit of nature. (½)

Q.3 Very short answer type question:- (i to x) / 𝒊 𝒙

(i) What are Cleistogamous flower. Give example. (1)

(ii) What is LH surge. / LH (1)

(iii) Why a Hemophilic father can never pass hemophilic gene to his son? (1)

(iv) What is Bioinformatics? / (1)

(v) Define Genetic drift. / (1)
(vi) What do you mean about “Baculovirus”. (1)

(vii) What is secondary treatment. / (1)

(viii) Write one advantage & one disadvantage of genetically modified crop. (1)

(ix) In a pond, there were 200 frogs, 40 more were born in a year. Calculate the
birth rate of the population. (1)

(x) In which region of the India, largest diversity of amphibians found? (1)

(Section-B)
Short answer type questions:- /
Q.4 Draw a labelled diagram of Human sperm. (1½)

Q.5 Write the full form of IUT, IUI, AI. (1½)

IUT, IUI, AI
Q.6 Write the difference between convergent & divergent evolution. (1½)

Q.7 Fill in the blanks 1, 2, 3 in given table:- (1½)

1, 2, 3
Name of microbe Name / Commercial Product

Bacteria / “1” Clot buster enzyme

“2” Trichoderma polysporum -A

Fungi/ Monoscus Purpurius “3”

Q.8 Draw a diagram of sparged stirred tank bioreactor. (1½)

Q.9 What is the difference between point mutation & frame shift mutation? (1½)
Q.10 What is the role of C-peptide in Human insulin? (1½)
𝐶
Q.11 What is the ecological principle behind the biological control method of managing
with pest insect? (1½)
(𝐼𝑛𝑠𝑒𝑡 𝑝𝑒𝑠𝑡)

Q.12 What is Leaching? / (1½)

Q.13 What are sacred groves? What is their role in conservation? (1½)

(Section-C)
Long answer type questions:-/
Q.14 Explain the development of female gametophyte with labeled diagram. (3)

OR
What is Apomixes? Explain various steps in the development of a dicot embryo
with diagram.

Q.15 What is pleiotropy? Write short note on Thalassemia.

OR
Explain the law of Dominance using a monohybrid cross.

Q.16 Taking example of a small pond ecosystem, explain how the four components of
this ecosystem function as a unit.

OR
What do you mean about Decomposition? What is the difference between Litter &
Detritus?

(Section-D)
Essay type questions:-/
Q.17 What is transcription? Explain the process of transcription in eukaryotic cell? (1+3=4)

OR
What is Lac operon? Explain the lac operon in Detail.

Q.18 What is metastasis? How is the cancerous cell different from a normal cell? (1+3=4)

OR
Explain the harmful effects of alcohol or drugs their abuses, prevention & control
the use of alcohol or drugs.