9b plants (biology)

Question 1

photosynthesis definition

Answer 1

a process that occurs in plants (and some other organisms) that involves a series of chemical reactions that convert ligtht energy into food called ‘glucose’

Question 2

word equation for photosynthesis

Answer 2

carbon dioxide + water –> glucose + oxygen

Question 3

number equation for photosynthesis

Answer 3

6CO2 + 6H20 –> C6H12O6 + 6O2

Question 4

chlorophyll definition

Answer 4

a green chemical that absorbs energy transferred by light and uses it to power photosynthesis (it is the pigment that makes plants green)

Question 5

reactants definition

Answer 5

the raw materials required for photosynthesis to occur

Question 6

limiting factors definition

Answer 6

the factors that limit the rate of speed of photosynthesis

Question 7

fill in the blanks: 1. _______ and 2. _______ are needed for photosynthesis to occur.

Answer 7

1. energy, 2. chlorophyll

Question 8

the energy transferred by light is stored in the…

Answer 8

glucose

Question 9

what is the test for starch?

Answer 9

iodine solution – if starch is seen on a leaf, the plant is going through photosynthesis

Question 10

what is the test for carbon dioxide?

Answer 10

lime water – lime water becomes milky when carbon dioxide is shaken/bubbled through it

Question 11

what is starch?

Answer 11

starch is a carbohydrate and a product of photosynthesis that stores energy

Question 12

xylem cells definition

Answer 12

the vascular tissue/vein that transports water throughout a plant’s body (made out of hollow dead cells)

Question 13

wilt definition

Answer 13

when plants become weak and begin to bend towards the ground

Question 14

what is the process of plants getting water?

Answer 14

1. water is taken out of the soil by the roots/root hair cells
2. water flows up xylem cells to the leaf

Question 15

how are roots adapted to their function?

Answer 15

by being branched and spread out to help them to absorb water from a large volume of soil

Question 16

why do plants need water to stay healthy?

Answer 16

water contains mineral salts (e.g. plants need nitrates to make proteins)

Question 17

how are root hair cells adapted to their function?

Answer 17

by having a large surface area to help them absorb water quickly

Question 18

what happens to plants when they don’t have enough water?

Answer 18

they wilt

Question 19

how does water prevent plants from wilting?

Answer 19

by filling up their cells (giving the plant structure) and keeping their leaves cool

Question 20

stomata definition

Answer 20

specialised pores or opening present in the upper epidermis of plant cells

Question 21

what controls the gas exchange in a plant?

Answer 21

stomata

Question 22

stomata function

Answer 22

air, containing carbon dioxide, diffuses into leaves through small holes called stomata

Question 23

why do leaves have a large surface area?

Answer 23

to absorb as much light as possible

Question 24

where does most photosynthesis occur?

Answer 24

in the palisade cells near the upper surface of the leaves

Question 25

what do palisade cells contain?

Answer 25

chloroplasts (an organelle)

Question 26

what do chloroplasts contain?

Answer 26

chlorophyll

Question 27

increasing the amount of ______ can speed up photosynthesis (give an example)

Answer 27

reactants (e.g. water, carbon dioxide, light)

Question 28

name 4 limiting factors

Answer 28

light intensity, water, temperature, carbon dioxide concentration

Question 29

aerobic respiration definiton

Answer 29

a series of chemical reactions where plant cells release the energy stored in the glucose

Question 30

word equation for aerobic respiration

Answer 30

glucose + oxygen –> carbon dioxide + water

Question 31

number equation for aerobic respiration

Answer 31

C6H12O6 + 6O2 –> 6CO2 + 6H20

Question 32

when does aerobic respiration occur?

Answer 32

constantly

Question 33

glucose definition

Answer 33

a type of sugar

Question 34

phloem vessels definition

Answer 34

the vascular tissue of a plant that carries foods made in the leaves during photosynthesis to all other parts of the plant

Question 35

name 3 functions of glucose

Answer 35

glucose can be used for…
1. respiration to release energy
2. making other substances that act as stores of energy (e.g. starch), which can be turned back into glucose for respiration when needed
3. making new materials for growth

Question 36

name 3 examples of how glucose can be used for making new materials for growth

Answer 36

1. cellulose to make cell walls
2. lipids to make cell membranes
3. proteins to make enzymes

Question 37

yield definition

Answer 37

an amount produced of an agricultural or industrial product

Question 38

biodiversity definition

Answer 38

the variety of all living things and their interactions

Question 39

what do modern farming methods cause?

Answer 39

environmental problems

Question 40

why is land cleared of hedges and trees and what problems does this cause?

Answer 40

to make more land for crops and to make it easier for machinery to move around –> destroys habitats … lack of roots can cause soil erosion

Question 41

what are 1. pesticides, 2. herbicides and 3. insecticides?

Answer 41

1. pest killers, 2. weed killers, 3. insect killers

Question 42

pesticides are used

Answer 42

to kill pests that compete with or harm the crops –> can kill useful organisms and pests + damages food webs

Question 43

fertilisers are used

Answer 43

they contain mineral salts that help plants to grow and increase the yield –> can was into streams and rivers and cause pollution so that the organisms in the water die

Question 44

varieties

Answer 44

varieties of plants are chosen that produce the highest yield –> the planning of huge areas of a single variety reduces biodiversity

Question 45

selective breeding process

Answer 45

1. farmers and plant breeders ‘select’ a plant with the certain characteristics they want
2. this organism is used to breed from
3. the offspring that have the best of these characteristics are bred from again

Question 46

cross-breeding definition

Answer 46

when two different varieties are bred together to try and produce offspring with characteristics from both varieties