L1.5 - Eukaryotic Cells

Question 1

What is the structure of ribosomes?

4

Answer 1

tiny organelles made of RNA + protein

consist of 1 large + 1 small sub-unit

not always attached to ER, many found floating in cytoplasm

have no membrane

Question 2

What is the function of ribosomes?

1

Answer 2

Site of protein synthesis

Question 3

What is the structure of the nucleus and nucleolus?

4

Answer 3

jelly like matrix

spherical

Nuclear envelope - double membrane

Nucleolus - smaller sphere inside

Question 4

What is the function of the nucleus and nucleolus?

3

Answer 4

produces RNA to make ribosomes (nucleolus)

Site of DNA replication + transcript (making mRNA)

Contains genetic code for each cell

Question 5

What is the structure of the endoplasmic reticulum (ER)?

2

Answer 5

Folded membranes (cisternae)

RER has ribosomes lining the cisternae

Question 6

What is the function of the endoplasmic reticulum (ER)?

2

Answer 6

RER - involved in protein synthesis

SER - Involved in the synthesis + storage of lipids

Question 7

What is the structure of the golgi apparatus?

2

Answer 7

Folded membranes making cisternae

Secretary vesicles pinch off from cisternae

Question 8

What is the function of the golgi apparatus?

4

Answer 8

package proteins for secretion

secrete carbs

transport + store lipids

form lysosomes

Question 9

What is the structure of lysosomes?

1

Answer 9

membrane bound vesicles secreted by golgi apparatus containing ‘hydrolytic enzymes’

Question 10

What is the function of lysosomes?

2

Answer 10

Secrete digestive enzymes outside the cell

breaks down ingested material or worn out organelles or destroys cells when they die

Question 11

What is the structure of mitochondria?

3

Answer 11

Double membrane

Inner membrane called cristae

a matrix - contains ribosomes, own DNA + enzymes for respiration

Question 12

What is the structure of chloroplasts?

4

Answer 12

Double membrane, forming an envelope

Has a colourless mixture called stomata (contains enzymes for photosynthesis)

has thylakoids floating in stomata

have genetic information + ribosomes

Question 13

What is the function of chloroplasts?

1

Answer 13

Site of photosynthesis

Question 14

What is the structure of the cell wall?

2

Answer 14

Plants - Made of microfibrils of the cellulose polymer

Fungi - Made of chitin, a nitrogen-containing polysaccharide

Question 15

What is the function of the cell wall?

3

Answer 15

provides structural support to plant

stops plant bursting when water moves in by osmosis

involved in transport of water into and throughout the plant

Question 16

What is the structure of the cell vacuole?

3

Answer 16

liquid filled space surrounded by a membrane (membrane called a tonoplast)

many are small (called vesicles)

all cells have one, plants have a large one

Question 17

What is the function of the cell vacuole?

4

Answer 17

storage (sugars + amino acids)

isolate substances which may be harmful to the rest of the cell

help maintain cell turgidity

Pigments may colour petals to attract pollinators

Question 18

What is the function of the mitochondria?

2

Answer 18

Site of aerobic respiration to produce ATP

DNA to code for enzymes needed in respiration

Question 19

What is the structure of plasma membrane?

2

Answer 19

In all cells

Had a phospholipid bilayer - molecules embed within + attached on the outside

Question 20

What is the function of plasma membrane?

1

Answer 20

Controls the entrance + exit of molecules