bacteria

Question 1

E. coli has no cholesterol in its cell-surface membrane. Despite this, the cell maintains a constant shape. Explain why.

Answer 1

Cell unable to change shape;

2. (Because) cell has a cell wall;
3. (Wall is) rigid / made of peptidoglycan / murein.

Question 2

Some proteases are secreted as extracellular enzymes by bacteria.

Suggest one advantage to a bacterium of secreting an extracellular protease in its natural environment.

Explain your answer.

Answer 2

To digest protein;

2. (So) they can absorb amino acids for growth / reproduction / protein synthesis / synthesis of named cell component;

OR

(So) they can destroy a toxic substance / protein;