b1 - cell structure and transport

Question 1

what is the equation for magnification?

Answer 1

magnification = image size / real size

Question 2

what is resolution?

Answer 2

the ability to clearly distinguish the individual parts of an object

Question 3

what is the resolving power of a microscope?

Answer 3

measure of how well you can distinguish between 2 points

Question 4

what are the structures in an animal cell?

Answer 4

nucleus
cytoplasm
cell membrane
mitochondria
ribosomes

Question 5

what is the function of the nucleus?

Answer 5

controls all activities of the cell
contains the genes

Question 6

what is the function of the cytoplasm?

Answer 6

a liquid gel where most chemical reactions take place

Question 7

what is the function of the cell membrane?

Answer 7

regulates what enters and leaves the cell
protects and supports the cell

Question 8

what is the function of the mitochondria?

Answer 8

where aerobic respiration occurs (releases energy for the cell)

Question 9

what is the function of the ribosomes?

Answer 9

where protein synthesis takes occurs

Question 10

what structures do plant cells have that animal cells don’t?

Answer 10

chloroplasts
cell wall
permanent vacuole

Question 11

what is the function of the cell wall?

Answer 11

made of cellulose, supports + strengthens the cell

Question 12

what is the function of the chloroplasts?

Answer 12

contain chlorophyll which absorbs light for photosynthesis

Question 13

what is the function of the permanent vacuole?

Answer 13

filled with cell sap to help keep the cell turgid

Question 14

what is a eukaryotic cell?

Answer 14

a cell that has a nucleus and organelles

Question 15

give examples of eukaryotic cells

Answer 15

plants
animals
fungi
protists

Question 16

what is a prokaryotic cell?

Answer 16

a cell without a nucleus
they are single felled living organisms

Question 17

give examples of prokaryotic cells

Answer 17

bacteria
archaea

Question 18

what structure does the dna in eukaryotic cells form?

Answer 18

chromosomes

Question 19

what structure does the dna in prokaryotic cells form?

Answer 19

plasmids (small rings of dna found in the cytoplasm)

Question 20

what is a flagella?

Answer 20

long, thin whip-like structure that helps organisms move through moist or wet surroundings

Question 21

what is differentiation?

Answer 21

the process by which a cell changes to become specialised for its job

Question 22

give examples of specialised cells

Answer 22

red blood cells
nerve cells
gamete cells
root hair cell
muscle cells
xylem + phloem cells
photosynthetic cells

Question 23

how are nerve cells specialised?

Answer 23

lots of dendrites to connect to other cells

a long axon carrying the nerve impulses

synapses at the ends to pass messages on

lots of mitochondria to provide enough energy

Question 24

how are (striated) muscle cells specialised?

Answer 24

contain special proteins that slide over eachother making the fibres contract

lots of mitochondria to release energy needed for contraction
term-51
store glycogen to be broken down + used in cellular respiration

Question 25

how are egg cells specialised?

Answer 25

large diameter for them to carry enough stored food contain stored food needed for early stages of development large, haploid nucleus contains genetic info

Question 26

how are sperm cells specialised?

Answer 26

long tail + streamlined head to help swim faster lots of mitochondria to release energy enzymes stored in the acrosome to digest through the egg large nucleus containing genetic info

Question 27

how is a root hair cell specialised?

Answer 27

increased surface area for water to move into cell large permanent vacuole to speed up movement of water by osmosis from soil across root hair cell lots of mitochondria to transfer energy needed for active transport of mineral ions into root hair cell

Question 28

how are red blood cells specialised?

Answer 28

large surface area that allows absorption of oxygen biconcave shape creates the large surface area for absorption of oxygen able to fold to travel through the capillaries small diameter allowing them to pass through small blood vessels

Question 29

how are palisade mesophyll cells specialised?

Answer 29

contain chlorophyll that absorbs light needed for photosynthesis usually positioned in continuous layers of leaves + outer layers of stem to absorb max amount of light large permanent vacuole to keep cell rigid as a result of osmosis

Question 30

how are xylem cells specialised?

Answer 30

hollow in the centre have very few sub-cellular structures so that water + mineral ions can easily flow through them spirals and rings of lignin to make them strong + help withstand pressure of water moving up plant

Question 31

how are phloem cells specialised?

Answer 31

end walls allow sugars through but support the tubes arranged end to end into tubes have companion cells in between them

Question 32

what is diffusion?

Answer 32

the net movement of particles of gas or any substance in solution from an area of high concentration to an area of low concentration down the concentration gradient

Question 33

what is net movement?

Answer 33

the overall movement of particles

Question 34

what factors affect rate of diffusion?

Answer 34

temperature surface area difference in concentration pressure

Question 35

what substances use diffusion?

Answer 35

gases eg oxygen, co2 glucose waste products eg urea

Question 36

what is gas exchange?

Answer 36

the process by which oxygen is transported to cells and carbon dioxide is transported from cells