Topic 6- Plant Structures and their Functions Flashcards Preview

Edexcel GCSE Biology > Topic 6- Plant Structures and their Functions > Flashcards

Flashcards in Topic 6- Plant Structures and their Functions Deck (69):
1

In a food chain, consumers eat other organisms. What word is used to describe organisms that make their own food?


producers


2

What process do plants and algae use to make their own food?

photosynthesis

3

In what sub-cellular part of a plant cell does photosynthesis occur?

chloroplast

4

What substance from the air do plants need for photosynthesis?

carbon dioxide

5

What substance from the ground do plants need for photosynthesis?

water

6

What organs do plants use to get water from the ground?

roots

7

How are roots adapted to getting water from the ground quickly?

large surface area, root hair cells

8

What energy-storing compound is made in photosynthesis?

glucose

9

Suggest one use for glucose in a plant.

respiration, making other substances

10

In what sub-cellular part of a plant cell does respiration occur?

mitochondria

11

What product of photosynthesis is a gas at room temperature?

oxygen

12

Plants photosynthesise. Name one other group of organisms that photosynthesise.

algae or cyanobacteria

13

What reactant in photosynthesis is a gas at room temperature?

carbon dioxide

14

What are all the materials that make up an organism known as?

biomass

15

In what subcellular parts of plants does photosynthesis occur?

chloroplasts

16

Where does all the energy originally come from in most food chains?

the Sun

17

What polymer inside chloroplasts is made from glucose?

starch

18

Name the main sugar that is transported around most plants.

sucrose

19

How are most leaves adapted to only allow gas exchange during the day?

stomata

20

What do we mean by the ‘rate’ of photosynthesis?

the speed of the reactions

21

What is a rate of reaction?


how fast a reaction happens


22

What do we call something that prevents a rate of reaction increasing?

limiting factor

23

If light intensity is a limiting factor, what happens to the rate of photosynthesis when it is increased?

The rate increases.

24

When there is plenty of light and plenty of carbon dioxide, suggest one factor that could be limiting.

temperature or water

25

What happens to the rate of photosynthesis as a plant is moved further away from a light source?

It decreases.

26

What relationship is shown by a straight line through the points on a scatter graph?

linear relationship

27

What sort of linear relationship is shown by a straight line through the origin?

direct proportion

28

Higher and Triple only- By what law does light intensity vary with distance?

inverse square law

29

Higher and Triple only- What is light intensity inversely proportional to?

distance squared

30

What happens to plants if they do not get enough water to fill their cells?

They wilt.

31

What term is used to describe the amount of a substance in a certain unit volume?

concentration

32

What term is used to describe the overall movement of particles from higher concentration to lower concentration?

diffusion

33

What term is used to describe the overall movement of solvent particles from higher concentration to lower concentration through a partially permeable membrane?

osmosis

34

What is the gradual change in concentration from one place to another called?

concentration gradient

35

What process do cells use to transport substances against their concentration gradient?

active transport

36

What adaptation do some root cells have in order to increase the amount of water they can absorb?

root hairs

37

Why do cells that use active transport often have a lot of mitochondria?

Active transport needs a lot of energy.

38

What do plants need nitrate ions for?

making proteins

39

Through what vessels is water moved up a plant?

xylem vessels

40

Through what tissue are sugars transported around a plant?

phloem tissue

41

What is the flow of water through a plant called?


transpiration


42

In what vessels does water flow?

xylem vessels

43

In what vessels are dissolved mineral ions carried?

xylem vessels

44

Give one other function of xylem vessels.

supporting the plant

45

What tissue is used for translocation?

phloem

46

Give the names of the two most common cells in phloem tissue.

sieve tubes and companion cells

47

Why do companion cells contain many mitochondria?

because they actively pump sucrose in and out of sieve tubes

48

If the humidity of the air around a plant is reduced, what happens to the rate of transpiration?

it increases

49

Which cells create the air spaces inside a leaf?

spongy cells

50

What term describes trees that lose their leaves in winter?

deciduous

51

In which tissue of a plant leaf does most photosynthesis occur?

palisade

52

Which tissue in a plant leaf consists of irregularly shaped cells that create air spaces?

sponge

53

Give one function of cuticle.

to prevent microorganisms entering/to prevent water entering/to reduce evaporation of water

54

What cells control the opening and closing of stomata?

guard cells

55

Explain why conifer trees have their stomata in pits.

to trap water vapour and reduce water loss

56

What word describes trees that lose their leaves in winter?

deciduous

57

Why do deciduous trees lose their leaves in winter?

to prevent water loss when water in the ground may not be available because it is frozen

58

Why is it an advantage for a plant root to grow downwards?

to anchor the plant/to reach water

59

Why is it an advantage for a plant shoot to grow towards the light?

to get energy for photosynthesis

60

What is a growth in response to a stimulus called?

tropism

61

What is a growth in response to the stimulus of light called?

photosynthesis

62

What is a growth away from light called?

negative phototropism

63

Name a part of a plant that shows negative phototropism.

root

64

What plant hormones cause phototropism?

auxins

65

What effect do auxins have on cells in a plant shoot?

cause them to elongate

66

What effect do auxins have on cells in a plant root?

stop them elongating

67

Name the growth response of a root in the direction of gravity.

positive gravitropism

68

Name the group of plant hormones that are used to help seeds germinate.

gibberellins

69

Name the plant hormone that is a gas and is used to ripen fruit.

ethene