Unit 2, Feeding the billions, Biology

Question 1

State what is happening to the human population explain why this could be a problem.

Answer 1

The population is increasing so food has to be grown but there is limited land.

Question 2

Suggest methods to produce more food in the world.

Answer 2

Irrigation            Green houses
Mechanical farming 
Plant rotation          Animals
Basic foods and less cash crops
Eating more vegetables

Question 3

Name the raw materials for photosynthesis.

Answer 3

water

carbon dioxide

Question 4

Name requirements for photosynthesis.

Answer 4

sunlight

chlorophyll

Question 5

Their products of photosynthesis.

Answer 5

glucose

oxygen

Question 6

Right equation for photosynthesis.

Answer 6

water + carbon dioxide -> glucose + oxygen
|
sunlight ] [ chlorophyll

Question 7

Describe what the main product of photosynthesis can be used for.

Answer 7

energy
cellulose
starch (storage)

Question 8

In the indicator used to test for starch and describe the colour change.

Answer 8

iodine solution

brown - no chlorophyll
blue/black - chlorophyll

Question 9

Explain each stage in the “testing a leaf for starch” process.

Answer 9

cut a leaf tissue
boil the leaf in water ( 2 mins )
boil leaf in ethanol
wash the alcohol off the leaf with cold water
put leaf on dimple plate with iodine solution
take leaf out and observe

Question 10

The green pigment found in leaves.

Answer 10

chlorophyll

Question 11

Explain the role of chlorophyll in photosynthesis.

Answer 11

to absorb light

Question 12

Name that cells/structures found in leaves.

Answer 12

Upper epidermis
wax cuticle
pallisade mesophyll 
mesophyll
spongy mesophyll
lower epidermis
guard cell with chloroplast 
stomata

Question 13

Explain how the cuticle of a plant help plants photosynthesise.

Answer 13

waterproof coating

Question 14

Explain how the upper epidermis help plants photosynthesise.

Answer 14

protective outer layer

Question 15

Explain how the palisade mesophyll cells help plants photosynthesise.

Answer 15

contain the most chlorophyll and where photosynthesis occurs

Question 16

Explain how the spongy mesophyll cells help plants photosynthesise.

Answer 16

absorbs extra sunlight and creates ear spaces

Question 17

Explain how the air spaces help plants photosynthesise.

Answer 17

Allows air/gases to and from photosynthesising cells

Question 18

Explain how the xylem vessel help plants photosynthesise.

Answer 18

hollow tube allowed passage of water

Question 19

Explain how the stomata helps plants photosynthesise.

Answer 19

Hole in epidermis that allows gasses in/out of the leaf.

Question 20

Explain how the guard cells help plants photosynthesise.

Answer 20

open/close stomata

Question 21

State whether the upper or lower epidermis as the most stomata.

Answer 21

lower

Question 22

State what a limiting factor is.

Answer 22

If a factor needed for photosynthesis is in short supply and is limiting the photosynthesis rate

Question 23

Name the factors which may limit photosynthesis in plants.

Answer 23

Temperature
Carbon dioxide concentration
Light intensity

Question 24

States several practical measurements of photosynthesis that can be made.

Answer 24

volume of oxygen per minute
mass of glucose produced per day
volume carbon dioxide uptake per min

Question 25

Name three elements required for healthy plant growth.

Answer 25

Nitrogen (N)
Phosphorus (P)
Potassium (K)

Question 26

Describe the symptoms of plant growth without phosphorus.

Answer 26

poorly developed roots

overall growth reduced

Question 27

Describe the symptoms of plant growth without nitrogen.

Answer 27

long thin roots
small yellow leaves
growth reduced

Question 28

Describe the symptoms of plant growth without potassium.

Answer 28

poorly developed flower

growth reduced