Bulk Transport

Question 1

Define

Answer 1

A type of active transport that moves large molecules or groups of
molecules – such as amino acids, proteins, signalling molecules, or pathogens – into or
out of the cell using vesicles.

Question 2

Exocytosis define

Answer 2

Type of bulk
transport that moves large
substances out of the cell

Question 3

Endocytosis

Answer 3

A type of bulk
transport that moves large
substances into the cell

Question 4

Exocytosis occurs because

Answer 4

Sometimes cells need to transport larger molecules out of the cell but due to their larger size they can’t use facilitated diffusion via a protein membrane

Question 5

Steps in exocytosis

Answer 5

1. Vesicular Transport - vesicle containing secretory products is transported to the
   plasma membrane
   2 Fusion – the membranes of the vesicle and cell fuse
   3 Release – the secretory products are released from the vesicle and out of the cell.

Question 6

Endocytosis why

Answer 6

Molecules are too large to use a protein channel and the cell often requires them to survive

Question 7

Three steps:

Answer 7

Fold – the plasma membrane folds inwards to form a cavity that fills with extracellular
fluid and the target molecules.
2 Trap – the plasma membrane continues folding back on itself until the two ends of the
membrane meet and fuse. This traps the target molecules inside the vesicle.
3 Bud – the vesicle (or endosome) pinches off from the membrane. It can then be
transported to the appropriate cellular location or fused with a lysosome for digestion.

Question 8

Phagocytosis and pinocytosis

Answer 8

Phagocytosis endocytosis of solid
material or food particles

Pinocytosis endocytosis of liquid
or dissolved substances