Tag: zoology

Questions Related to zoology

For two closely related species, the DNA would be

zoology structure of chromosome, cell cycle and cell division structure of dna nucleic acid heredity and inheritance

  1. Completely different

  2. Somewhat different

  3. Very different

  4. Very similar

  5. Identical

Show answer
Correct Option: D
Explanation:

Species that are very closely related have very similar DNA with only minor differences. They are related through a common ancestor. 

The base pairs of DNA are correctly shown as

zoology structure of chromosome, cell cycle and cell division structure of dna nucleic acid heredity and inheritance

  1. A $\equiv $ T and C = G

  2. A = T and C = G

  3. A = T and C $\equiv $ G

  4. A $\equiv $ T and C $\equiv $ G

Show answer
Correct Option: C
Explanation:

In DNA, purines pairs with pyrimidines. Adenine pairs with Thymine with double hydrogen bond and Guanine pairs with Cytosine with the help of triple hydrogen bond.

Diameter of DNA is/Wilkin's X-ray diffraction showed DNA diameter to be

zoology structure of chromosome, cell cycle and cell division structure of dna nucleic acid heredity and inheritance

  1. $200 \mathring{A}$

  2. $100 \mathring{A}$

  3. $20 \mathring{A}$

  4. $50 \mathring{A}$

Show answer
Correct Option: C
Explanation:
DNA has the double helical structure where the two strands are tightly coiled over each other. B- DNA has right-handed helix with the major and minor groove. The diameter of the DNA is 20 A$^o$. The number of base pairs in one turn is 10 and the distance between base pairs is 3.4 A$^o$. The total length of one turn of DNA is 34 A$^o$.
So, the correct answer is option C.


Two nucleotides in a strand are linked through H-bond form a dinucleotide.

zoology structure of chromosome, cell cycle and cell division structure of dna nucleic acid heredity and inheritance

  1. True

  2. False

Show answer
Correct Option: B
Explanation:

  • The two strands of the double helix DNA have base pairing between complementary purines and pyrimidines. Adenine pairs with Thymine or vice versa by two hydrogen bonds and Guanine pairs with Cytosine or vice versa by three hydrogen bonds. 
  • The two nucleotides on the same strand are linked through phosphodiester bond between 5' phosphate group of one mononucleotide and 3' OH group of other mononucleotide, to form a dinucleotide.
Hence, the statement given in the question is incorrect.
So, the correct answer is 'False'.

Which of the following is TRUE regarding sense and antisense strands?

zoology structure of chromosome, cell cycle and cell division structure of dna nucleic acid heredity and inheritance

  1. Both the strands are present on RNA

  2. Both the strands are present on DNA

  3. Sense strand is on DNA and antisense on RNA

  4. Sense strand is on RNA and antisense on DNA

Show answer
Correct Option: B
Explanation:

Both sense and antisense strands are present in DNA as these act as antisense strand acts as a template during transcription and sense strand has the same sequence as mRNA in the nucleus.

So, the correct option is B.

In which of the following DNA sequences the sequence of nucleotides is the same when one strand is read left to right and the other strand is read right to left?

zoology structure of chromosome, cell cycle and cell division structure of dna nucleic acid heredity and inheritance

  1. RFLP

  2. RAPD

  3. VNTR

  4. Palindromic sequence

Show answer
Correct Option: D
Explanation:
A palindromic sequence is a sequence made up of nucleic acids within double helix of DNA or RNA that is the same when reading from 5' to 3' on one strand and 5' to 3' on the other, complementary strand. 
So, the correct answer is 'Palindromic sequence'.

The double-helix structure of DNA was described by

zoology structure of chromosome, cell cycle and cell division structure of dna nucleic acid heredity and inheritance

  1. Watson

  2. J.D. Watson and F. H. C. Crick

  3. Maurice Wilkins

  4. All of the above

Show answer
Correct Option: D
Explanation:

The structure of DNA was deciphered by Watson and Crick in 1953 on the basis of X-ray diffraction data generated by Wilkins, Astbury and Franklin. Wilkins, Watson and Crick were awarded Nobel prize for their model in 1962.
So, the correct answer is option D.

The characteristic feature of Z-DNA is

zoology structure of chromosome, cell cycle and cell division structure of dna nucleic acid heredity and inheritance

  1. Left handed

  2. Right handed

  3. 12 base pairs in each turn

  4. Both A and C

Show answer
Correct Option: D
Explanation:

DNA duplex of Watson and Crick is right handed and is called as B-DNA. Z-DNA is left handed double helix, which contains zigzag backbone of phosphodiester bonds and 12 base pairs per turn. The diameter of Z-DNA is 18 $\mathring A$ as against B-DNA diameter of 20 $\mathring A$.
So, the correct answer is option D.

Which of the following has higher surface area (SA) to volume (V) ratio?

zoology structure of chromosome, cell cycle and cell division structure of dna nucleic acid heredity and inheritance

  1. Red blood cell

  2. Nails

  3. DNA

  4. Human Hair

Show answer
Correct Option: C

A five carbon sugar with molecular formula $C _5H _{10}O _4$

zoology structure of chromosome, cell cycle and cell division structure of dna nucleic acid heredity and inheritance

  1. Deoxyribose

  2. Ribose

  3. Glucose

  4. Lactose

Show answer
Correct Option: A
Explanation:

Glucose (C$ _6$H$ _1$$ _2$O$ _6$), Deoxyribose (C$ _5$H$ _1$$ _0$O$ _4$), Lactose (C$ _1$$ _2$H$ _2$$ _2$O$ _1$$ _1$), Ribose (C$ _5$H$ _1$$ _0$O$ _5$)

So, the correct answer is option A.