12th Standard Syllabus & Materials
12th Standard
TN 12th Computer Applications மின்னணு தரவு பரிமாற்றம் Sample Question Papers Study Material - QB365 Set A
NEW12th Standard
TN 12th Computer Applications மின் - வணிக பாதுகாப்பு அமைப்புகள் Sample Question Papers Study Material - QB365 Set A
NEW12th Standard
TN 12th Computer Applications மின்னணு செலுத்தல் முறைகள் Sample Question Papers Study Material - QB365 Set A
NEW12th Standard
TN 12th Computer Applications மின் - வணிகம் Sample Question Papers Study Material - QB365 Set A
NEW12th Standard
TN 12th Computer Applications திறந்த மூல கருத்துருக்கள் Sample Question Papers Study Material - QB365 Set A
NEW12th Standard
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 One Mark Questions with Answer Key 2020 - Part Seven
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.
Extinction of Dodo bird and extinction of Calvaria tree is the example of:
Mass extinction
Co-extinction
Over exploitation
Exotic species invasion
2.
Identify the incorrect statement
Water is a universal solvent
Water has less surface tension
Water is heavier than air
When freezes water contracts
3.
Assertion (A): On diagnosis, Ramu is reported to have underdeveloped testis and gynaecomastia.
Reason (R): His karyotype reveals XXY condition
A is right but R is wrong
R explains A
Both A and R are wrong
Both and R are right but R is not the correct explanation of A
4.
Legalized marriageable age of female in India is __________
19 years
20 years
18 years
21 years
5.
According to Darwin, the organic evolution is due to
Intraspecific competition
Interspecific competition
Competition within closely related species.
Reduced feeding efficiency in one species due to the presence of interfering species.
6.
The diagram shows an important concept in the genetic implication of DNA. Fill in the blanks A to C.
A B C
DNA ⟶ mRNA ⟶ protein⟶ proposed by__________
A - transcription, B-replication, C- James Watson
A - transcription, B-transcription, C-Erwin
A - transcription, B - translation, C - Francis Crick
A- transcription, B- extension, C-Rosalind Frankin
7.
A few statements with regard to sexual reproduction are given below:
i. Sexual reproduction does not always require two individuals
ii. Sexual reproduction generally involves gametic fusion
iii. Meiosis never occurs during sexual reproduction
iv. External fertilization is a rule during sexual reproduction
Choose the correct statements from the options below:
i and iv
i and ii
ii and iii
i and iv
8.
Human exploitation of forests, oceans etc leads to _____________-
Chromosomal mutations
Artificial Selection
Gene recombination
Natural selection
9.
Cryopreservation of embryos are done when _____
When eggs are not available
Sperm count is less
More embryos are available than the required
there is abnormality in the embryo
10.
The hormone _____ produced by anterior pituitary plays a major role in lactation.
oxytocin
prolactin
progesterone
oestrogen
11.
The transfer of sperms by the male into the female genital tract is called _____
implantation
parturition
insemination
gastrulation
12.
Yellowish eyes is a symptom of_______
Plague
Measles
Hepatitis
Sleeping sickness
13.
All the following animals are continuous breeders, except.
Frogs
Honey bees
Poultry
Rabbit
14.
True about interferon is that
It is synthetic antiviral agent
It inhibits viral replication in cells
It is specific for a particular virus
It causes infection
15.
In the E- waste generated by the Mobile Phones, which among the following metal is most abundant?
Copper
Silver
Palladium
Gold
16.
Which of the following is considered a hotspots of biodiversity in India?
Western ghats
Indo-gangetic plain
Eastern Himalayas
Both (a) and (c)
17.
Which of the following one is used as a Biosensors?
Electrophoresis
Bioreactors
Vectors
Electroporation
18.
What is the basis for the difference in the synthesis of the leading and lagging strand of DNA molecules?
Origin of replication occurs only at the 5' end of the molecules
DNA ligase works only in the 3' → 5' direction
DNA polymerase can join new nucleotides only to the 3' end of the growing stand.
Helicases and single-strand binding proteins that work at the 5' end
19.
The Androgen Binding Protein (ABP) is produced by ________.
Leydig cells
Hypothalamus
Sertoli cells
Pituitary gland
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.
Due to incomplete linkage in maize, the ratio of parental and recombinants are ______.
50:50
7:1:1:7
96.4: 3.6
1:7:7:1
22.
Which of the following phenotypes is not possible in the progeny of the parental genotypic combination IAIO x IAIB?
AB
O
A
B
23.
24.
Transmitting tissue is found in ______.
Micropylar region of ovule
Pollen tube wall
Stylar region of gynoecium
Integument
1.
(b)
Co-extinction
2.
(b)
Water has less surface tension
3.
(b)
R explains A
4.
(c)
18 years
5.
(b)
Interspecific competition
6.
(c)
A - transcription, B - translation, C - Francis Crick
7.
(d)
i and iv
8.
(b)
Artificial Selection
9.
(c)
More embryos are available than the required
10.
(b)
prolactin
11.
(c)
insemination
12.
(c)
Hepatitis
13.
(a)
Frogs
14.
(b)
It inhibits viral replication in cells
15.
(a)
Copper
16.
(d)
Both (a) and (c)
17.
(a)
Electrophoresis
18.
(c)
DNA polymerase can join new nucleotides only to the 3' end of the growing stand.
19.
(c)
Sertoli cells
20.
(c)
Antigen binding site on variable regions
21.
(b)
7:1:1:7
22.
(b)
O
23.
(d)
24.
(c)
Stylar region of gynoecium
12th Standard Syllabus & Materials
12th Standard
TN 12th Computer Applications களப்பெயர் முறைமை (DNS) Sample Question Papers Study Material - QB365 Set A
NEW12th Standard
TN 12th Computer Applications வலையமைப்பு எடுத்துக்காட்டுகள் மற்றும் நெறிமுறைகள் Sample Question Papers Study Material - QB365 Set A
NEW12th Standard
TN 12th Computer Applications கணினி வலையமைப்பு ஓர் அறிமுகம் Sample Question Papers Study Material - QB365 Set A
NEW12th Standard
TN 12th Computer Applications PHP-உடன் MySQL-ஐ இணைத்தல் Sample Question Papers Study Material - QB365 Set A
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
Tamilnadu Stateboard Standards
