Active Transport 5.4

Question 1

Active Transport

Answer 1

The movement of molecules or ions from a low to high concentration so against the concentration gradient

Question 2

What is needed in active transport?

Answer 2

ATP is needed as it is not a passive process

Question 3

Describe the process of active transport

Answer 3

The molecule or ion needing to be transported will bind to the carrier protein on the outside of the cell and ATP will bind to the carrier protein on the inside of the cell and become hydrolysed to form an ADP and a phosphate. The ADP will detach and the remaining phosphate will change the shape of the carrier protein, opening up the inside of the cell so the molecule will have been actively transported as it detaches. The phosphate will also detach and bind with ADP to form ATP. With the phosphate gone, the carrier protein will return to its normal shape.

Question 4

Bulk Transport

Answer 4

Active transport that is used for transporting large structures like hormones or enzymes that cannot be carried by a carrier protein.

Question 5

Endocytosis

Answer 5

This is the transport of materials from outside to inside the cell and there is phagocytosis which is the transport of solids and pinocytosis which is the transport of liquids. The materials will approach the membrane and when it makes contact, the membrane will invaginate and fold around it to make a vesicle called an endosome. This will then be released into the cytoplasm to take part in specific functions.

Question 6

Exocytosis

Answer 6

The transport of materials from the inside of the cell to the outside. Transport vesicles are made by the Golgi apparatus and they will approach and fuse to the membrane, releasing its contents to the outside of the cell

Question 7

Why does bulk transport require ATP?

Answer 7

ATP is needed for the vesicles to travel along the cytoskeleton and for the membranes to make the endosomes and for the membranes to then fuse back together