Plant nutrition and transport in plants

Question 1

Define photosynthesis

Answer 1

process which plants manufacture carbohydrates from raw materials using energy from light

Question 2

Are plants autotrophs

Answer 2

yes

Question 3

Define autotrophs

Answer 3

organisms that are able to make their own food

Question 4

Purpose of chlorophyll (2)

Answer 4

transfers light energy into chemical energy in molecules

used for synthesis (production) of carbohydrates

Question 5

Word equation of photosynthesis

Answer 5

carbon dioxide + water –> glucose + oxygen

Question 6

Balanced chemical equation of photosynthesis

Answer 6

6CO2 + 6H2O –> C6H12O6 + 6O2

Question 7

Name layers of the structure of a leaf in order (7)

Answer 7

waxy cuticle

upper epidermis

palisade mesophyll

Spongy mesophyll

Lower epidermis

Guard cells

waxy cuticle

Question 8

Features of palisade mesophyll cells (4)

Answer 8

where most photosynthesis occurs

contains many chloroplasts

columnar shape allows many cells to be tightly packed to maximise absorption

found close to upper surface of leaf

Question 9

Stomata and guard cells function (3)

Answer 9

play role in gas exchange

gases enter and exit through stomata

guard cells open or close in response to environment

Question 10

Function of xylem

Answer 10

transports water and minerals from root to leaves

Question 11

Function of phloem

Answer 11

transports sugars (sucrose) and amino acids from leaves to other parts of plant

Question 12

By which process is glucose produced

Answer 12

photosynthesis

Question 13

What is glucose used for (5)

Answer 13

energy

growth of shoots

growth of young leaves

growth of fruit

root growth

Question 14

Purpose of sucrose (2)

Answer 14

converted from glucose

less reactive than glucose so not lost if transported

Question 15

Where is sucrose transported

Answer 15

phloem

Question 16

Purpose of starch

Answer 16

storage of glucose

Question 17

Function of nitrate ions

Answer 17

synthesis (production) of amino acids

Question 18

Function of magnesium ions

Answer 18

chlorophyll production

Question 19

Deficiency of magnesium and nitrate ions (2)

Answer 19

stunted growth

yellow leaves

Question 20

What chemical is used to test for starch

Answer 20

iodine

Question 21

Experiment layout for testing starch availability in plants (7)

Answer 21

remove leaf from plant

place in beaker of boiling water for 30 seconds to break open cells

place in boiling tube of ethanol inside the beaker of boiling water - removes chlorophyll from leaves

remove leaf after 1 minute using forceps

rinse leaf with cold water

spread leaf on white tile and drip iodine on it

positive result is blue/black

Question 22

Define variegated leaves

Answer 22

leaves which have green and white parts

Question 23

Answering 7 mark experiment question (8)

Answer 23

independent variable

dependent variables

control variable (2)

safety precautions

how you will set up the experiment

how and how often you record data

how you will analyse results

what results show

Question 24

Determinants for the rate of photosynthesis (3)

Answer 24

light intensity

CO2 amount

temperature

Question 25

Define limiting factor

Answer 25

factor at lowest level which limits rate of reaction

Question 26

Purpose of water in plants (2)

Answer 26

needed for photosynthesis maintain turgor pressure and keep structure

Question 27

How is water absorbed into roots (3)

Answer 27

osmosis high concentration of minerals in root cells water drawn into cells from high water potential (soil) to low water potential (cells)

Question 28

Adaptation of root cells

Answer 28

root hair cells increase surface area for osmosis

Question 29

Transport of water in plant (3)

Answer 29

once inside root cells water passes through xylem vessels up stem into leaves if leaf photosynthesizing, water lost through open stomata process called transpiration

Question 30

Define transpiration (3)

Answer 30

loss of water from a plant by evaporation at surface of mesophyll cells also diffuses out as water vapour through stomata draws more water and minerals through xylem and up roots

Question 31

Define transpiration stream

Answer 31

flow of water through plant taking water up roots

Question 32

Pathway of water through roots, stem and leaf (4)

Answer 32

root hair cells root cortex cells xylem mesophyll cells

Question 33

Purpose of lignin in xylem vessels

Answer 33

supports structure

Question 34

How does water move upwards in the xylem (7)

Answer 34

transpiration pull made by water potential gradient between roots and leaves water evaporates at surface of mesophyll cells water vapour diffuses through stomata creates water potential gradient causes lower water potential compared to higher water potential in roots water absorbed by root hair cells water moves up xylem as unbroken column of water molecules - held together by cohesion

Question 35

4 main factors which affect rate of transpiration (4)

Answer 35

Light intensity Temperature wind speed humidity

Question 36

How does light intensity impact rate of transpiration (3)

Answer 36

greater light intensity --> more stomata open for photosynthesis more stomata --> more transpiration all stomata open --> further increase in light intensity won't affect rate of transpiration

Question 37

How does temperature affect rate of transpiration (2)

Answer 37

greater temperature --> faster the particles in the air move faster particles --> more water particles evaporate from leaf --> increases transpiration

Question 38

How does wind speed affect rate of transpiration (3)

Answer 38

increase in wind speed --> moves water particles surrounding leaf away increases water potential gradient between inside and outside of leaf increases rate of transpiration

Question 39

How does humidity affect rate of transpiration (3)

Answer 39

more humid --> more water in air reduces water potential gradient between inside and outside of leaf transpiration slows down

Question 40

Experiment for investigating rate of transpiration (4)

Answer 40

bubble potometer to estimate rate of transpiration as transpiration occurs xylem sucks up more water bubble will move along capillary tube measure distance moved by air bubble every minute to calculate rate of transpiration

Question 41

Define translocation

Answer 41

movement of sugars (sucrose) and amino acids in phloem of plant

Question 42

Define source

Answer 42

where sugar is produced or supplied to plant

Question 43

Define sink

Answer 43

where substance is used or converted to another substance

Question 44

What is the source and sink in summer (2)

Answer 44

leaves are source roots are sink

Question 45

What is the source and sink in winter (2)

Answer 45

roots are source leaves are sink

Question 46

Where is xylem and phloem in root cross-section (2)

Answer 46

xylem is large hollow X centre phloem on outer

Question 47

Where is xylem and phloem on stem cross-section (2)

Answer 47

xylem on inside phloem on outside

Question 48

Where is xylem and phloem on leaf cross-section (2)

Answer 48

xylem above phloem underneath

Question 49

When and Why is active transport used to take in ions (3)

Answer 49

active transport is movement of particles from area of low concentration to area of high concentration against concentration gradient using energy mineral ions in higher contents in plant than soil root hair cells use active transport to get nutrients

Question 50

How does cohesion work in a plant (4)

Answer 50

water molecules are cohesive tension created at top of xylem tube when water moves out of xylem cells tension pulls water molecules up xylem into leaf which pulls molecules out root cortical cells into root xylem tubes

Question 51

State the type of cell through which water enters a plant

Answer 51

root hair cell

Question 52

State the type of energy required for photosynthesis

Answer 52

light energy

Question 53

Adaptation of xylem (4)

Answer 53

hollow - to reduce resistance/allow efficient flow large cross-sectional area/wide - to allow transport of large volume of water lignin to provide support waterproof to prevent water loss

Question 54

Explain how mineral ions enter a plant (2)

Answer 54

enter into root hair cell by active transport moves against concentration gradient using energy

Question 55

Which chemical is a product of photosynthesis that moves out of a green leaf through its stomata?

Answer 55

oxygen

Question 56

In a leaf, water moves from the surface of a mesophyll cell and then out of the leaf into the atmosphere What is the correct order of the processes involved?

Answer 56

evaporation --> diffusion

Question 57

The list shows features of a plant leaf: 1 air spaces between spongy mesophyll cells 2 chloroplasts in mesophyll cells 3 contains a natural insecticide 4 xylem vessels close to mesophyll cells Which features are adaptations for photosynthesis?

Answer 57

1,2 and 4