12th Standard Syllabus & Materials
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TN 12th Computer Applications மின்னணு தரவு பரிமாற்றம் Sample Question Papers Study Material - QB365 Set A
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TN 12th Computer Applications மின்னணு செலுத்தல் முறைகள் Sample Question Papers Study Material - QB365 Set A
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TN 12th Computer Applications மின் - வணிகம் Sample Question Papers Study Material - QB365 Set A
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TN 12th Computer Applications திறந்த மூல கருத்துருக்கள் Sample Question Papers Study Material - QB365 Set A
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TN 12th Computer Applications வலையமைப்பு வடமிடல் Sample Question Papers Study Material - QB365 Set A
Published on: 05/11/2020
12th Standard Biology English Medium Free Online Test 1 Mark Questions 2020 - Part Ten
Download Tamil Nadu 12th Standard Biology question papers, model tests, one-mark questions, important questions, and public exam papers in PDF format. Free study materials and answer keys for TN State Board students.
Questions + Answers key
Take MCQ Biology Test1.
The sequence of bases in coding strand of DNA is GAGTTAGCAGGC, then the sequence of codons in primary transcript is ___________
C U C A U A C G C C C G
C U C A A U C G U C C G
U C A G A U C U G C G C
U U C A A U C G U G C G
2.
Whose experiment finally provided convincing evidence that DNA is the genetic material?
Griffith experiment
Avery, Macleod and McCarty's experiment
Hershey-Chase experiment
Urey-Miller's experiment
3.
The type of antibodies present in colostrum.
Ig E
Ig M
Ig A
Ig B
4.
Which of the following contributes to the seminal plasma?
(i) Cowper's gland
(ii) Seminal vesicles
(iii) Prostate gland
(iv) Bulbourethral gland
ii, iii and ii
i, ii, and iii
i, iii and iv
all the above
5.
Which of the following types of asexual reproduction is noticed in Amoeba?
Sporulation
Encystment
Binary fission
All the above
6.
Which one of the following statement is correct?
stem cells are specialized cells
there is no evidence of the existence of gills during embryogenesis of mammals
all plant and animal cells are totipotent
Ontogeny repeats phylogeny
7.
Usage of _____ greatly reduces the risk of STI.
IUDS
Latex Condoms
Saheli
Lippes loop
8.
______ is needed for normal functioning of reproductive structures
Vitamin A
Vitamin E
Vitamin B
Vitamin C
9.
The hormone ____ brings about powerful contraction of uterine muscles during child birth.
Relaxin
Oestrogen
Progesterone
Oxytocin
10.
______ is a hormone produced by sertoli cells.
Inhibin
Progesterone
Testosterone
Oestrogen
11.
The sexual union of young individuals produced immediately after the division of the parent Cell is called _____
Paedogamy
hologamy
merogamy
isogamy
12.
Messelson and Stahl ___________.
proved that RNA is the genetic material
proved that protein synthesis is dependent on DNA
proved the semi conservative mode of DNA replication.
discovered enzymes involved in replication
13.
Scientists who contributed to karyotyping _______.
Tjio and Levan
John Cotto
Bridges
Wiener
14.
Tectona grandis is coming under family _____.
Lamiaceae
Fabaceae
Dipterocaipaceae
Ebenaceae
15.
Depletion of which gas in the atmosphere can lead to an increased incidence of skin cancer?
Ammonia
Methane
Nitrous oxide
Ozone
16.
Which one of the following are at high risk extinction due to habitat destruction?
Mammals
Birds
Amphibians
Echinoderms
17.
18.
E. coli cell grown on 15N medium are transferred to 14N medium and allowed to grow for two generations. DNA extracted from these cells is ultracentrifuged in a cesium chloride density gradient. What density distribution of DNA would you expect in this experiment?
One high and one low density band
One intermediate density band.
One high and one intermediate density band.
One low and one intermediate density band
19.
The process which the sperm undergoes before penetrating the ovum is _____.
Spermiation
Cortical reaction
Spermiogenesis
Capacitation
20.
Paratope is an
Antibody binding site on variable regions
Antibody binding site on heavy regions
Antigen binding site on variable regions
Antigen binding site on heavy regions
21.
The point mutation sequence for transition, transition, transversion and transversion in DNA are ______.
A to T, T to A, C to G and G to C
A to G, C to T, C to G and T to A
C to G, A to G, T to A and G to A
G to C, A to T, T to A and C to G
22.
Which of the following is not correct?
Three or more alleles of a trait in the population are called multiple alleles
A normal gene undergoes mutations to form many alleles
Multiple alleles map at different loci of a chromosome
A diploid organism has only two alleles out of many in the population
23.
24.
Which of the following represent megagametophyte?
Ovule
Embryo sac
Nucellus
Endosperm
1.
(b)
C U C A A U C G U C C G
2.
(c)
Hershey-Chase experiment
3.
(c)
Ig A
4.
(d)
all the above
5.
(d)
All the above
6.
(d)
Ontogeny repeats phylogeny
7.
(b)
Latex Condoms
8.
(b)
Vitamin E
9.
(d)
Oxytocin
10.
(a)
Inhibin
11.
(a)
Paedogamy
12.
(c)
proved the semi conservative mode of DNA replication.
13.
(a)
Tjio and Levan
14.
(a)
Lamiaceae
15.
(d)
Ozone
16.
(a)
Mammals
17.
(b)
18.
(d)
One low and one intermediate density band
19.
(d)
Capacitation
20.
(c)
Antigen binding site on variable regions
21.
(b)
A to G, C to T, C to G and T to A
22.
(c)
Multiple alleles map at different loci of a chromosome
23.
(b)
24.
(b)
Embryo sac
12th Standard Syllabus & Materials
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Tamilnadu Stateboard 12th Standard Subjects
Maths
Chemistry
Physics
Biology
Computer Science
Business Maths and Statistics
Economics
Commerce
Accountancy
History
Computer Applications
Biology
Computer Technology
Computer Applications
Computer Science
Business Maths and Statistics
Commerce
Economics
Maths
Chemistry
Physics
Computer Technology
History
Accountancy
Tamil
English
French
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