Cell Biology

Question 1

function of ribosomes

Answer 1

site of protein synthesis

Question 2

what is osmosis

Answer 2

the movement of water molecules through a selectively permeable membrane from an area of higher concentration to an area of lower concentration

Question 3

what is active transport

Answer 3

the movement of particles across a membrane against a concentration gradient

Question 4

define selectively permeable

Answer 4

some substances are let through but others are not

Question 5

what is diffusion

Answer 5

the movement of particles from an area of a higher concentration to an area of lower concentration

Question 6

what is meant by the term plasmolysed

Answer 6

when a cell shrinks/shrivels as a result of osmosis

Question 7

what is meant by the term turgid

Answer 7

when a cell swells/bursts due to osmosis

Question 8

what is glucose broken down into during aerobic respiration

Answer 8

pyruvate

Question 9

what is fermentation

Answer 9

the type of respiration that doesnt require oxygen

Question 10

is lactate produced in animals or plant

Answer 10

animals

Question 11

what is the word equation for aerobic respiration

Answer 11

glucose + oxygen –> carbon dioxide + water + energy

Question 12

what is the function of the cell membrane

Answer 12

to control what enters and exits the cell

Question 13

what is the role of the vacuole

Answer 13

stores sap

Question 14

what is the cell wall made from

Answer 14

cellulose

Question 15

what is the function of the nucleus

Answer 15

contains genetic material which controls the activities of the cell

Question 16

what do chromosomes contain

Answer 16

DNA

Question 17

what is a gene

Answer 17

a small section of DNA found on a chromosome

Question 18

what are the complementary base pairs

Answer 18

adenine and thymine, cytosine and guanine

Question 19

how are proteins synthesised

Answer 19

the DNA contains the genetic coding for the protein.
in the nucleus, the two DNA strands unzip around the gene.
the mRNA is made which moves out of the nucleus and into the cytoplasm, then attaches to a ribosome.
amino acids that match the code on the mRNA are joined together in the right order which makes the protein.

Question 20

what is an enzyme

Answer 20

biological catalysts which speed up chemical reactions in the body

Question 21

hormones are…

Answer 21

chemical messengers which carry messages around the body

Question 22

what are antibodies

Answer 22

they are produced by white blood cells and help fight disease

Question 23

what happens during a degradation reaction

Answer 23

a substrate binds to an enzymes active site and is then broken down into more than one product

Question 24

describe a synthesis reaction

Answer 24

where more than one substrates bind to an enzyme and are joined together into one product molecule

Question 25

what is an optimum temperature

Answer 25

the temperature at which enzymes work best at

Question 26

how does pH affect enzymes

Answer 26

low or high pH levels can cause an enzymes active site to denature

Question 27

what are the steps in genetic engineering

Answer 27

the section of DNA with the useful gene is identified. the gene is cut out from the chromosome using enzymes. a plasmid is taken from a bacteria cell. the plasmid is cut open using enzymes and the gene is inserted. the plasmid is then inserted into a host bacterial cell.