Biology 9700 · AS & A Level · The immune system

The immune system — practice question

Lysosomes are organelles in cells that contain enzymes called acid hydrolases. Fig. 6.1 illustrates some processes that take place in animal cells.
(a)[2]

Identify the cell structures marked A and E.

(b)[1]

State the role of the structures labelled F.

(c)[1]

Name the process used for bacteria to enter the cell at C.

(d)[3]

Using the processes at B and D in Fig. 6.1, outline how acid hydrolases function in lysosomes.

(e)[2]

Carrier proteins in lysosomal membranes keep the pH below that of the surrounding cytoplasm by transporting hydrogen ions. Suggest how these carrier proteins sustain the lower pH inside lysosomes.

Worked solution & mark scheme

This 9-mark question has a full step-by-step worked solution and mark scheme. One marking point: Rough endoplasmic reticulum correctly identified

  • Full mark scheme, point by point
  • Step-by-step worked solution
  • Write your answer & get it marked instantly by AI