1.5 Respiration Biology N5

Question 1

what form of energy is found in food

Answer 1

chemical energy

Question 2

what do all cells require

Answer 2

energy

Question 3

how is the chemical energy in food releasd

Answer 3

it is released through enzyme controlled reactions called respiration

Question 4

what is made from the breakdown of glucose in respiration

Answer 4

the glucose is used to make ATP energy

Question 5

what cellular activities that use the ATP energy

Answer 5

muscle cell contraction, cell division, protein synthesis, active transport of ions or molecules across the cell membrane, transmission of nerve impulses in neurons

Question 6

how many stages are there in respiration

Answer 6

two stages

Question 7

describe the 1st stage of respiration

Answer 7

during the first stage one glucose mo0lecule is brokendown into 2 pyruvate molecules which happens in the cytoplasm of the cell and results in making two molecules of ATP to breakdown the pyruvate any further i sdependent on wetrher oxygen is present or absent

Question 8

explain the processs of the 2nd stage of respiration

Answer 8

pyruvate is brooken down into to carbon dioxide and water when oxygen is present this takes place in the mitochondria of the cell and results in a large number of ATP molecules

Question 9

what is the word equation for aerobic respiration

Answer 9

gluycose+oxygen>carbondioxide+water+lots of water

Question 10

describe the relation between energy requirment of a cell and number of mitochondria present in the cell

Answer 10

the higher the energy requirement of the cell the more number of mitochondrioa in the cell and the lower the energy requirment the lower number of mitochondria in the cell

Question 11

name examples of cells with lots of mitochondria and a high energy requirment

Answer 11

muscle,companion, sperm and nueron cells

Question 12

what is used to measure rate of respiration

Answer 12

respirometer

Question 13

explain how a respirometer is used to measure rate of respiration

Answer 13

a respiring organism is placed in the specimen chamber which has a perforated platform which is used to stop the organism touching the soda lime which could harm, it the soda lime is there to remove carbondioxide given out by the organism the starting level of the coloured liquid is noted the organism respires aerobically for a known period of time like an hour for example the organism wiil take up oxygen from the enclosed space causingf the coloured liquid to rise the organism also releases the same volume of carbon dioxide which is absorbed by the soda lime after the one hour is up the new level of coloured liquid is noted the difference imn coloured liquid represents the volume of oxygen taken up by the respiring organism in one hour which is the rate of respirationof the organism in cm cubed per hour

Question 14

how do you calculate the rate ofrespiration

Answer 14

you divide the difference in level of liquid by the number of minutes

Question 15

what key variables affect the rate of respiration

Answer 15

temprature glucose concentration oxygen level

Question 16

how maqny stages are in fermentation

Answer 16

2 stages

Question 17

what happens during the first stage of fermentation

Answer 17

glucose is brokendown into two molecules of pyruvate this is done in the cytoplasm and the pyruvate is then used to make 2 molecules of ATP

Question 18

what needs to happen for fermentation to occur

Answer 18

fgermantation occurs only if oxygen is absent

Question 19

explain the the second stage of fermentation

Answer 19

in the second stage the 2 pyruvate is broken down into lactate because no oxygen is present and occurs in the cytoplasm and no further ATP is made due to no nenergy being released

Question 20

what is the word equation foer fermentation inn animal cells

Answer 20

glucose>lactate+energy (2xATP)

Question 21

describe the first stage of fermentation in plant and yeast cells

Answer 21

glucose is broken down into 2 pyruvate which makes 2 ATP

Question 22

explaimn the second stage of fermentation in plant and yeast cells

Answer 22

in the second stage pyruvate is brokjen down into carbon dioxide and ethanol and no more ATP is made