Unit 2 - Cells and Organelles 2

Question 1

Proteins are made…(where?)

Answer 1

Mainly at the ribosomes attached to the RER. These proteins are stored in the RER until they can be processed and packaged at the golgi apparatus. Some ribosomes are free in the cytoplasm and the proteins they produce also stay in the cytoplasm.

Question 2

In the RER proteins are..

Answer 2

folded and processed, being modified in ways such as having sugar chains added.

Question 3

Proteins are transported from the RER to the…

Answer 3

Golgi apparatus in vesicles.

Question 4

At the Golgi apparatus the proteins…

Answer 4

undergo further processing where sugar chains are trimmed or more are added.

Question 5

Proteins are transported in/out/around cells in…

Answer 5

vesicles.

Question 6

Secretory cells, which release hormones or enzymes, have more…

Answer 6

rough endoplasmic reticulum than cells that do not release proteins.

Question 7

Proteins may be stored…(in which organelle?)

Answer 7

in the rough endoplasmic reticulum until they are needed by the Golgi apparatus

Question 8

The cytoskeleton is made of which three components:

Answer 8

1. Microfilaments - contractile fibres formed from the protein actin.
2. Microtubules - globular tubulin proteins polymerised to form tubes that act as a scaffold structure determining the shape of a cell. Also act as tracks for the movements of organelles.
3. Intermediate fibre - fibres that give mechanical strength to cells and help maintain their integrity.

Question 9

Microtubules and microfilaments

Answer 9

Support the cell’s organelles keeping them in position,
strengthen the cell and help maintain it’s shape,
they’re responsible for the transport of organelles and materials within the cell.

Question 10

Vacuole

Answer 10

Membrane lined sac in plant cells containing cell sap. Large permanent vacuoles as used to maintain turgor. The membrane of the vacuole is called the tonoplast. It is selectively permeable. if vacuoles appear in animal cells they are small and transient.

Question 11

Prokaryotic vs. eukaryotic - cell size

Answer 11

Prokaryotic - extremely small, less than 2 µm diameter

Eukaryotic - Larger Cells, 2-200 µm diameter

Question 12

Prokaryotic vs. eukaryotic - Nucleus & DNA

Answer 12

Prokaryotic - No nucleus, DNA free in cytoplasm, DNA is circular, organised by proteins folding and condensing DNA.

Eukaryotic - Nucleus Present, DNA inside nucleus in form of chromosomes, DNA is Linear. Organised by DNA molecules associating with histones to form chromatin, which is condensed to form chromosomes.

Question 13

Prokaryotic vs. eukaryotic - Extra chromosomal DNA

Answer 13

Prokaryotic - found in plasmids

Eukaryotic - found in chloroplasts and mitochondria

Question 14

Prokaryotic vs. eukaryotic - Organelles

Answer 14

Prokaryotic - non-membrane bound

Eukaryotic - both non-membrane bound and membrane bound

Question 15

Prokaryotic vs. eukaryotic - Cell wall

Answer 15

Prokaryotic - peptidoglycan

Eukaryotic - chitin in fungi, cellulose in plants

Question 16

Prokaryotic vs. eukaryotic - Ribosomes

Answer 16

Prokaryotic - smaller, 70S

Eukaryotic - larger, 80S

Question 17

Prokaryotic vs. eukaryotic - Cystoskeleton

Answer 17

Prokaryotic - present but basic

Eukaryotic - present, more complex (microfilaments, microtubules, & intermediate fibres)

Question 18

Prokaryotic vs. eukaryotic - Reproduction

Answer 18

Prokaryotic - binary fission

Eukaryotic - asexual or sexual

Question 19

Prokaryotic vs. eukaryotic - Cell type

Answer 19

Prokaryotic - unicellular

Eukaryotic - unicellular or multicellular

Question 20

Prokaryotic vs. eukaryotic - Cell membrane

Answer 20

Present in both