organelles

Question 1

cell wall function [2]

Answer 1

1. maintains shape
2. prevents bursting

Question 2

prokaryotes

Answer 2

organisms that do not have a true nucleus
- dna not protected by the nucleus

Question 3

plasma membrane

Answer 3

semi-permeable and selective barrier surrounding the cell

Question 4

cytoplasm

Answer 4

internal fluid component of the cell

Question 5

bound ribosomes

Answer 5

synthesises protein used outside the cells

Question 6

free ribosomes

Answer 6

synthesises protein used inside the cell

Question 7

rough er

Answer 7

starts folding of polypeptide

Question 8

smooth er

Answer 8

synthesises the phospholipid
- used in cell membrane + cholesterol

Question 9

cells with ERs

Answer 9

undertake secretory activities

Question 10

mitochondria function

Answer 10

aerobic respiration
- requires higher concentration of oxygen and glucose

Question 11

mitochondria structure

Answer 11

• double membrane
• inner membrane higher folded into internal cristae

Question 12

golgi apparatus

Answer 12

• modifies polypeptides into their functional state
• sorts, concentrates and packs proteins into vesicles
• exocytosis

Question 13

lysosome structure

Answer 13

membranous sacs filled with hydrolytic enzymes

Question 14

lysosome function

Answer 14

• breakdown/hydrolysis of macromolecules
• contains lysozymes (digestive enzyme)

Question 15

plasmids

Answer 15

autonomous circular DNA molecules that may be transferred between bacteria (horizontal gene transfer)

Question 16

pili

Answer 16

hair like extensions that
1. enable adherence to surfaces (attachment pili)
2. mediate bacterial conjugation (sex pili)

Question 17

slime capsule

Answer 17

thick polysaccharide layer used for protection against desiccation (drying out) and phagocytosis

Question 18

vesicles

Answer 18

move substances in + out of cell
either to
1. within the cell (lysosomes)
2. plasma membrane out of cell
3. secretion to the outside of the cell (exostosis)

Question 19

compartmentalised because [3]

Answer 19

1. control concentration of chemicals needed
2. avoid enzymes
3. mRNA can be modified after transcription before it leaves the nucleus

Question 20

typical cells contains [2 + reason]

Answer 20

1. DNA as genetic material
2. cytoplasm
   - dissolve substances
   - carry out metabolic reactions

Question 21

prokaryote dna is..

Answer 21

naked + in a loop

Question 22

eukaryote plasma membrane

Answer 22

enclosing a compartmentalised cytoplasm with 80S ribosomes

Question 23

nucleus [5]

Answer 23

• with chromosomes made of DNA
• store genetic material as chromatin
• bound to histones
• contained in a double membrane with pores
• inner region called nucleolus: site of ribosome assembly

Question 24

eukaryotes has cytoskeleton of…

Answer 24

microtubules and microfilaments

Question 25

advantages of compartmentalisation in the cytoplasm

Answer 25

- concentration of metabolites and enzymes and the separation of incompatible biochemical processes eg. lysosomes and phagocycotic vacuoles

Question 26

plasma membrane composed of

Answer 26

lipids

Question 27

structure of cytoskeleton

Answer 27

filamentous scaffolding within the cytoplasm

Question 28

cytoskeleton function [2]

Answer 28

- provides internal structure - mediates intracellular transport less developed in prokaryotes

Question 29

peroxisome function

Answer 29

catalyses breakdown of toxic substances and other metabolites

Question 30

peroxisome structure

Answer 30

membranous sac containing a variety of catabolic enzymes

Question 31

centrioles function

Answer 31

- microtubule organising centre - arrangement of the mitotic spindle during cell division - serve as anchor points for microtubules in the cytoplasm, cilia and flagella

Question 32

centriole structure

Answer 32

- paired cylindrical -shaped organelles composed of nine groups of three microtubules organised symmetry - fibrous protein inside the cells

Question 33

chloroplast structure [2]

Answer 33

- double membrane - internal stacks of membranous discs (thylakoids)

Question 34

chloroplast function

Answer 34

site of photosynthesis- manufactured organic molecules are stored in various plastids

Question 35

cell wall structure

Answer 35

- external outer covering made of cellulose - not an organelle

Question 36

cell wall function [2]

Answer 36

- provides support and mechanical strength - prevents excess water uptake

Question 37

plastids present in

Answer 37

plants

Question 38

cell wall present in

Answer 38

plants + fungi

Question 39

how do plants and fungi differ [3]

Answer 39

1. no chloroplasts 2. diff cell wall material 3. decomposers

Question 40

centrioles present in

Answer 40

animals

Question 41

cilia present in

Answer 41

animal + plant

Question 42

flagella present in

Answer 42

animal + plant

Question 43

vesicle's journey

Answer 43

- formed in the rough ER - received by Golgi apparatus - Golgi apparatus forms vesicles that transport substances to membrane

Question 44

y is cell wall not an organelle

Answer 44

dont have a specific metabolic function