Question

1. during transcription, what enzyme is responsible for synthesizing mrna?

a. dna polymerase
b. rna polymerase
c. trna
d. rrna

1. how does the sickle cell trait provide an advantage in malaria - endemic regions?

a. it hinders the malaria parasite’s ability to thrive in red blood cells
b. it increases susceptibility to malaria
c. it causes a more severe form of malaria
d. it eliminates the malaria parasite from the environment

1. what happens during the termination phase of dna replication?

a. new dna strands are synthesized
b. nucleotides are added to the growing strand
c. dna strands are unwound
d. specific sequences signal the completion of replication

Explanation:

Question 1

• Option a: DNA Polymerase is involved in DNA replication, not transcription.
• Option b: RNA Polymerase is the enzyme that synthesizes mRNA from a DNA template during transcription.
• Option c: tRNA (transfer RNA) is involved in translation, carrying amino acids.
• Option d: rRNA (ribosomal RNA) is a component of ribosomes, involved in translation.

• Option a: The sickle - cell trait (having one copy of the sickle - cell gene) makes the red blood cells less favorable for the malaria parasite (Plasmodium) to thrive, thus providing a survival advantage in malaria - endemic regions.
• Option b: Sickle - cell trait does not increase susceptibility to malaria; in fact, it reduces it.
• Option c: Sickle - cell trait does not cause a more severe form of malaria.
• Option d: Sickle - cell trait does not eliminate the malaria parasite from the environment.

• Option a: New DNA strands are synthesized during the elongation phase of DNA replication.
• Option b: Nucleotides are added to the growing strand during the elongation phase.
• Option c: DNA strands are unwound during the initiation phase of DNA replication.
• Option d: During the termination phase of DNA replication, specific sequences (like termination sites) signal that the replication process is complete.

Answer:

b. RNA Polymerase

Question 2