Physiology

Question 1

What is smooth endoplasmic reticulum

Answer 1

site of steroid synthesis and detoxification of drugs and poisons
Also location of G6PD

Question 2

What is a promotor site?

Answer 2

Site where RNA polymerase 2 and other transcription factors bind upstream from gene

Question 3

Introns vs exons

Answer 3

exons contain genetic information for protein
Introns do not but help regulate

Question 4

What does rough endoplasmic reticulum do?

Answer 4

site of secretory proteins
Synthesis, folding and modification of proteins

Question 5

Phases of cell cycle

Answer 5

M - cell separates
G1 - longest, cell grows and produces energy
S - DNA synthesis/replication
G2 - organelles and proteins produced

Question 6

Function of p53

Answer 6

usually inhibits G1 progression to S

Question 7

Phases of mitosis

Answer 7

Prophase - condense chromosomes
Prometaphase
Metaphase - chromosomes move to the middle
Anaphase - spindle fibres pulled by centromeres to pull apart DNA
Telophase - nuclear membrane forms

Question 8

Function of DNA poly 3

Answer 8

elongated 5 -> 3 prime
on 3 -> 5 side makes okazaki fragments

Question 9

What is DNA ligase

Answer 9

joins okazaki fragments

Question 10

How is DNA stored

Answer 10

wraps around histone to form nucleosome

Question 11

What is non-homologous end joining?

Answer 11

double stranded DNA break repair -> some DNA is lost

Question 12

What is homologous recombination and when is it defective

Answer 12

dsDNA is repaired using a complementary strand (caused by ionising radiation)
defective in BRCA1 and fanconi anaemia