section 1: cell structure - topic 2: organelles working together

Question 1

where are proteins made?

Answer 1

at the ribosomes.

Question 2

what do the ribosomes on the RER do?

Answer 2

make proteins that are excreted or attached to the cell membrane.

Question 3

what do the free ribosomes in the cytoplasm do?

Answer 3

make proteins that stay in the cytoplasm.

Question 4

what happens to the proteins produced at the RER?

Answer 4

they’re folded & processed (i.e. sugar chains are added) in the RER.
then they’re transported from the RER to the golgi apparatus in vesicles.
at the golgi apparatus, the proteins may undergo further processing.
the proteins enter more vesicles to be transported around the cell (i.e. glycoproteins (found in mucus) move to the cell surface & are secreted.

Question 5

what is the cytoskeleton?

Answer 5

the network of protein threads running through the cytoplasm.

Question 6

in eukaryotic cells, what are the protein threads arranged as?

Answer 6

microfilaments (very thin protein strands).
microtubules (tiny protein cylinders).

Question 7

what are the 4 main functions of the cytoskeleton?

Answer 7

1. the microtubules & microfilaments support the cell’s organelles, keeping them in position.
2. they help to strengthen the cell and maintain its shape.
3. they’re responsible for the transport of organelles & materials within the cell.
4. the proteins of the cytoskeleton can also cause the cell to move.

Question 8

why is the cytoskeleton being dynamic good?

Answer 8

it allows it to respond to changes in the cell and carry out its functions.