Question 1

Which of the following best describes the Central Dogma of Biology?

Accepted Answer

DNA is transcribed into RNA, which is then translated into protein.

Question 2

During transcription, which enzyme is responsible for synthesizing RNA from a DNA template?

Accepted Answer

RNA polymerase

Question 3

If a DNA sequence reads 5'-ATGCGT-3', what is the corresponding mRNA sequence produced during transcription?

Accepted Answer

5'-AUGCGU-3'

Question 4

Which codon serves as the start codon for translation in eukaryotes, and what amino acid does it code for?

Accepted Answer

$$	ext{AUG}$$; Methionine

Question 5

A mutation changes a codon from $$	ext{UAC} to$$ $$	ext{UAA}. $$What is the consequence of this mutation?

Accepted Answer

A stop codon is introduced, terminating translation.

Question 6

Which of the following statements about exons and introns is correct?

Accepted Answer

Introns are removed during mRNA processing, while exons are expressed.

Question 7

In the cell cycle, what is the primary purpose of the G1 checkpoint?

Accepted Answer

To check for sufficient nutrients and growth factors before DNA replication.

Question 8

Which phase of mitosis is characterized by chromosomes lining up at the cell's equator?

Accepted Answer

Metaphase

Question 9

A cell with uncontrolled growth and loss of cell cycle checkpoints is most likely to become:

Accepted Answer

A cancer cell

Question 10

In the mouse cross shown, what is the phenotypic ratio of agouti:black:albino offspring?

Accepted Answer

$$9:3:4$$

Question 11

Which of the following best explains why multiple codons can code for the same amino acid?

Accepted Answer

The genetic code is degenerate.

Question 12

A male with genotype $$X^hY ($$where $$h is a $$recessive allele for hemophilia) and a female carrier $$X^HX^h$$ have children. What is the probability that a son will have hemophilia?

Accepted Answer

$$0.25$$

Question 13

Which biotechnology technique is used to separate DNA fragments by size?

Accepted Answer

Gel electrophoresis

Question 14

If a restriction enzyme recognizes the sequence $$5'-GAATTC-3'$$ and cuts between G and A, how many fragments will result from digesting a circular DNA molecule with two such sites?

Accepted Answer

2

Question 15

Which of the following is true about the difference between DNA and RNA?

Accepted Answer

RNA contains uracil, while DNA contains thymine.

Question 16

A mutation in the gene for pigment production in mice (allele 'c') results in no pigment. If two heterozygous agouti mice ($$AaCc) $$are crossed, what fraction of their offspring will be albino?

Accepted Answer

$$\frac{4}{16}$$

Question 17

Which process is responsible for making millions of copies of a specific DNA sequence in the laboratory?

Accepted Answer

Polymerase Chain Reaction (PCR)

Question 18

During which phase of mitosis do sister chromatids separate and move toward opposite poles?

Accepted Answer

Anaphase

Question 19

Which of the following best describes the function of ribosomes in the cell?

Accepted Answer

They synthesize proteins from mRNA.

Question 20

If a protein is 100 amino acids long, what is the minimum number of nucleotides required in the coding region of the mRNA?

Accepted Answer

$$300$$

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