Exam questions

Question 1

Describe the structure and function of the nucleus.

Answer 1

The nucleus contains a nuclear envelope and pores. It also has DNA with histones. This is where DNA replication occurs . This is also where the production of rNA occurs

Question 2

What is the polymer of the fungal wall ?

Answer 2

Chitin

Question 3

Explain how the use of antibiotics has led to antibiotic-resistant strains of bacteria
becoming a common cause of infection acquired when in hospital?

Answer 3

First point - Some bacteria have alleles for resistance
Second point - Resistant bacteria
survive/reproduce
Third point - There is a high frequency of resistance allele in bacterial population

Question 4

Define the quaternary structure of a protein?

Answer 4

More than 1 polypeptide

Question 5

Describe how the scientists could use aseptic techniques to transfer 0.3 cm3 of C. difficile in liquid culture from a bottle onto an agar plate.

Answer 5

First point - Wash hands with soap
Second point - Use sterile pipette/syringe to transfer bacteria
Third point - Remove bottle lid and flame neck of bottle;

Question 6

Describe how the scientists would remove large organelles from this suspension of
cell contents.

Answer 6

First point -Use centrifuge at
low speed increasing sequence of speed
Second point - Large organelles removed in first pellet

Question 7

Describe the transport of carbohydrate in plants

Answer 7

1 - . Sucrose actively transported into phloem cell
2 - By companion cells
3 - Lowers water potential in phloem and water
enters from xylem by osmosis
4 - Produces higher hydrostatic pressure
5 - Mass flow to respiring cells

Question 8

Describe the complete digestion of starch by a mammal.