Respiration

Question 1

define respiration

Answer 1

the release of energy from food

Question 2

where is energy released from food

Answer 2

in all the cells mitochondrias of the body

Question 3

define energy

Answer 3

the ability to do work

Question 4

define work

Answer 4

work is done when a force moves an object

Question 5

word equation for respiration

Answer 5

glucose + oxygen = energy + carbon dioxide + water

Question 6

chemical equation for respiration

Answer 6

C6H12O6 + 6O2 = energy + 6CO2 + 6H2O

Question 7

how is respiration and photosynthesis a chemical process

Answer 7

involves a number of steps where new substances are formed

Question 8

how is respiration a biological process

Answer 8

takes place in living cells and uses enzymes

Question 9

what are the 7 characteristics of life

Answer 9

Movement Respiration Sensitivity Growth Reproduction Excretion Nutrition

Question 10

what three factors affect respiration

Answer 10

glucose , oxygen availability

temperature

Question 11

why does temperature affect respiration

Answer 11

enzymes can’t work if it’s too cold

enzymes are killed if it’s too hot

Question 12

investigate how temperature affects rate of respiration

Answer 12

four water baths with 10,20,30,40C. test tube with glucose solution and yeast in each, left for 6 minutes. Observe different heights of foam.
CONCLUSION: an increase in temp from 10 to 40 causes an increase in rate of respiration

Question 13

3 ways earth depends on photosynthesis

Answer 13

provide food, oxygen and clean air

Question 14

define photosynthesis

Answer 14

the way green plants make their own food by using light

Question 15

word equation for photosynthesis

Answer 15

carbon dioxide + water, chlorophyll/sunlight glucose + oxygen

Question 16

chemical equation for photosynthesis

Answer 16

6CO2 + 6H2O chlorophyll/sunlight C6H12O6 + 6O2

Question 17

how does photosynthesis happen?

Answer 17

• the plant gets all the stuff needed for the equation
• co2 and water combine in chloroplasts to make glucose by using energy from sunlight .
• oxygen is given off as a waste product

Question 18

how does the plant get carbon dioxide ?

Answer 18

from air through tiny pores on the leaf called stomata

Question 19

how does the plant get water?

Answer 19

from the soil through roots

Question 20

how does the plant get sunlight?

Answer 20

chlorophyll in chloroplasts of leaf cells absorb it

Question 21

what energy conversion happens in photosynthesis?

Answer 21

light to chemical

Question 22

what 3 factors affect photosynthesis?

Answer 22

co2 bc it reacts w water
temperature bc of enzymes
light bc it transforms to chemical energy

Question 23

show that light is necessary for photosynthesis

Answer 23

place plant in darkness for 24 hours to destarch it. then cover a leaf with aluminium foil w paper clips. then leave in sunlight for 6 hours. Test two leaves for starch:
put in boiling water to soften
place a test tube with methylated spirits in the beaker with hot water. put leaf inside to remove chlorophyll - it will become white . water shouldn’t boil bc alcohol has a lower boiling rate
put leaves back in hot water to remove alcohol
place on white tile to observe colour change
drop iodine solution - blueblack has starch

Question 24

how to use knowledge of factors of photosynthesis to increase crop yields ? 3

Answer 24

increase light w artificial lights
increase co2 by burning gas in greenhouses
increase temperature

Question 25

how is photosynthesis a chemical reaction

Answer 25

involves a number of steps where new substances are formed

Question 26

how is photosynthesis a biological reaction

Answer 26

takes place in living cells and involves enzymes