Gas Exchange And Transport In Plants

Question 1

What does a plant cell contain?

Answer 1

Nucleus
Cytoplasm
Cell membrane
Mitochondria
Cell wall
Ribosome
Vacuole
Chloroplast

Question 2

Are plants unicellular or multicellular?

Answer 2

Multicellular

Question 3

What do the chloroplasts in the plant cell do?

Answer 3

Carry out photosynthesis

Question 4

How do plants store carbohydrates?

Answer 4

As starch

Question 5

What is the plant cell wall made of?

Answer 5

Cellulose

Question 6

Examples of plants

Answer 6

Rose
Daffodil
Oak

Question 7

Which organs does the vascular system contain?

Answer 7

Roots
Stem
Leaf

Question 8

What is the function of a root hair cell?

Answer 8

To absorb water

Question 9

What is a root hair cell’s adaptation?

Answer 9

Large surface area

Question 10

What does a plant need?

Answer 10

Minerals and water from the soil

Question 11

What are mineral ions?

Answer 11

Naturally occurring inorganic substances

Question 12

Which mineral ions do plants need?

Answer 12

Magnesium ions
Nitrate ions

Question 13

Why are magnesium ions needed in a plant?

Answer 13

To make chlorophyll

Question 14

What is chlorosis caused by?

Answer 14

Magnesium deficiency (in plants)

Question 15

What is chlorosis?

Answer 15

Yellowing of leaves due to lack of chlorophyll

Question 16

Why are nitrate ions needed in a plant?

Answer 16

For protein synthesis

Question 17

What does a nitrate deficiency in a plant cause?

Answer 17

Stunted growth

Question 18

Glucose + nitrogen —> …?

Answer 18

Glucose + nitrogen —> AMINO ACID

Question 19

What are amino acids?

Answer 19

Building blocks of proteins

Question 20

What is a fertiliser?

Answer 20

Chemicals that farmers add to the soil to replace missing minerals

Question 21

Why are fertilisers needed?

Answer 21

When crops are harvested, minerals are removed from the ground

Question 22

What is a common fertiliser?

Answer 22

NPK

Question 23

What is the stem in a plant used for?

Answer 23

Transporting nutrients and water around the plant

Question 24

What is the stem of a plant made of?

Answer 24

2 special vascular tissues

Question 25

What are the 2 vascular tissues?

Answer 25

Xylem Phloem

Question 26

What is a leaf?

Answer 26

Organ found at the end of stems

Question 27

What is the function of the leaf?

Answer 27

To do photosynthesis

Question 28

Features of leaves

Answer 28

Green Thin Wide Veins Shiny on one side

Question 29

Wore equation for photosynthesis

Answer 29

light Carbon dioxide + water —> glucose + oxygen

Question 30

Chemical equation for photosynthesis

Answer 30

6CO2 + 6H2O —> C6H12O6 + 6O2

Question 31

What is the function of the xylem?

Answer 31

To carry water and minerals around the plant

Question 32

What is the function of the phloem?

Answer 32

To carry sugar (sucrose) and amino acids around the plant

Question 33

What is the stomata?

Answer 33

Tiny ‘mouths’ (gaps) on the underside of a leaf which allows carbon dioxide in

Question 34

Why is the stomata only open for as short a time as possible?

Answer 34

To minimise water loss

Question 35

What is the main problem in the stomata?

Answer 35

The water will diffuse out of any gaps really easily

Question 36

What do guard cells do?

Answer 36

Control the size of the stomata

Question 37

What are guard cells sensitive to?

Answer 37

Light —> close at night when photosynthesis isn’t taking place and they don’t need CO2

Question 38

Why is the stomata only open the underside of a leaf?

Answer 38

It is more shaded - makes it cooler so less water will evaporate To allow carbon dioxide into the leaf

Question 39

Turgid means …?

Answer 39

Open

Question 40

Flaccid means …?

Answer 40

Closed

Question 41

When are guard cells usually open?

Answer 41

When there is lots of water and when it is light

Question 42

What is the lower epidermis?

Answer 42

Layer of epidermal tissue for protection Contains guard cells

Question 43

What is the vein?

Answer 43

Connects to the stem Provides water and minerals from the root Takes away sugars

Question 44

What is the spongy mesophyll?

Answer 44

White layer near the middle of the leaf Has lots of air gaps to store carbon dioxide and easily diffuse to the next layer (gas exchange)

Question 45

What is the palisade mesophyll?

Answer 45

Green layer near the tip of the leaf Contains lots of chloroplasts for photosynthesis

Question 46

What is the upper epidermis?

Answer 46

Layer of epidermal tissue for protection Thin and transparent to allow sunlight to pass through to get to the chloroplasts in the palisade cells

Question 47

What happens once photosynthesis produces sugar molecules?

Answer 47

They’re carried to the rest of the plant by the phloem

Question 48

What is the main problem for a leaf?

Answer 48

Water loss (from the top and bottom of the leaf)

Question 49

What is the waxy cuticle?

Answer 49

On the top of the lead Thin waterproof layer of lipids that the water can’t get through

Question 50

Which structures help to minimise water loss?

Answer 50

Guard cells which can close the stomata Waxy cuticle

Question 51

What is the meristem tissue?

Answer 51

Made up of plant stem cells Found in the growing parts of the plant (tips of the roots and shoots)

Question 52

What can the meristem tissue do?

Answer 52

Differentiate into loads of different cell types so that the plant can grow

Question 53

Does phloem transport things up or down?

Answer 53

Both

Question 54

What is phloem made of?

Answer 54

Living cells

Question 55

What is at the end of each cell (phloem)?

Answer 55

A sieve plate which has pores to allow substances through

Question 56

What is phloem not?

Answer 56

Not a hollow tube

Question 57

Does phloem have a nucleus?

Answer 57

No

Question 58

How is phloem controlled and kept alive?

Answer 58

By companion cells

Question 59

Does phloem have thin or thick walls?

Answer 59

Thin walls

Question 60

Why does phloem have thin walls?

Answer 60

Easier for sugars to flow = efficient transport

Question 61

Does xylem transport things up or down?

Answer 61

Up

Question 62

Where does phloem transport things from and to?

Answer 62

From the leaves to the roots and stem

Question 63

Where does xylem transport things from and to?

Answer 63

From the roots to the stem and leaves

Question 64

What is xylem made of?

Answer 64

Dead cells which form hollow tubes

Question 65

Does xylem have thin or thick walls?

Answer 65

Thick walls

Question 66

What are xylem walls strengthened by?

Answer 66

Lignin

Question 67

Why are xylem wall’s thick and strengthened by lignin?

Answer 67

To cope with pressure

Question 68

Movement of water throughout a plant

Answer 68

1) water enters root hair cells by osmosis 2) water moves through the root cortex cells by osmosis 3) water moves into the xylem 4) water is drawn up the xylem 5) water enters mesophyll cells (palisade and spongy) 6) water evaporates and leaves through the stomata

Question 69

What does photosynthesis do?

Answer 69

Converts light energy into chemical energy (glucose)

Question 70

Why does the leaf have a large surface area?

Answer 70

To absorb light For gas exchange through the stomata

Question 71

Why are leaves very thin?

Answer 71

Shorter diffusion distance for the gases from the bottom (Increases the rate of diffusion)

Question 72

What does turgid mean?

Answer 72

Guard cells are full of water and swollen

Question 73

What is the root hair cell an adaption for?

Answer 73

To increase surface area to volume ratio for absorption

Question 74

How do mineral ions enter a root hair cell?

Answer 74

Via active transport

Question 75

How does water enter a root hair cell?

Answer 75

Via osmosis