Leaves Structure

Question 1

What is osmosis

Answer 1

Movement of water molecules from a high to low conc through a partially permeable membrane down the concwntration gradient

Question 2

What will happen if a red blood cell was in pure water

Answer 2

The water molecules will move into the cell causing it to burst

Question 3

What is the core practical for osmosis

Answer 3

-cut potatoes into cylinder
-make sure they are all the same length
-record each mass before
-add different amounts of sucrose solution into water
-leave for amount of time
-remove and dry the potatoes and record mass change

The higher the percent of sucrose solution the lower the mass will be because there will be a smaller mass of water in the potato

Question 4

Name the layers of the leaf

Answer 4

Waxy cuticle
Upper epidermis
Palisade mesophyll
Spongy mesophyll
Lower epidermis

Question 5

How is a leaf adapted to stop water loss

Answer 5

Waxy cuticle
Guard cells which open and close according to the amount if water

Question 6

Why is the upper epidermis transparent

Answer 6

For sunlight to pass through to the palisade mesophyll for photosynthesis

Question 7

What is a meristem tissue

Answer 7

Stem cells found in growth parts of the plant like tips of roots and shoots

Question 8

What is active transport and where does it get it’s energy from

Answer 8

Movement of mineral particles across membrane from low top high concentration gets energy from respiration

Question 9

How do plants absorb minerals

Answer 9

Can’t absorb by diffusion because its against the concentration gradient

They absorb it by root hair cells which also absorb water

Question 10

What is transpiration and how

Answer 10

Evaporation of water from the leaves.

The movement of water up the plant from the roots then out the stomata

Question 11

What is translocation

Answer 11

dissolved food is transported through the phloem in plants

Question 12

Factors affecting transpiration

Answer 12

Temperature increases because more energy
Light increases because stomata open for longer
Wind increases the rate at which water diffuses out

Question 13

Factors affecting photosynthesis

Answer 13

Light co2 temp lack of chlorophyll

Question 14

What happens in light intensity during photosyntyesis

Answer 14

Goes up then plataues meaning other limiting factor

Question 15

Co2 level affecting rate of photosynthesis

Answer 15

Goes up the platuaes means other limting factor

Question 16

Temperature affecting photosynthesis

Answer 16

Rises then falls due to the enzymes becoming denatures

Question 17

How do farmers increase the rate of photosynthesis

Answer 17

Green houses
Stops pests

Fake light when its dark

Pump more co2 into the atmosphere

Fertilisers

Paraffin which release light and co2

Question 18

Photosynthesis equation

Answer 18

Carbon dioxide + Water -> Glucose + Oxygen

6Co² + 6H²O -> C⁶ H12 O⁶ + 6o²

Question 19

Explain the process of diffusion in leafs

Answer 19

Water is taken from the soil by the roots then transported to the leaves via the xylem. The co2 diffuses into the leaves through the stomata

Question 20

Why do plants want glucose

Answer 20

Save as starch for later or for respiration

Question 21

What are the main uses of glucose in plants

Answer 21

Cellular respiratin-break down glucose to release energy

Make cellulose- makw strong cell walls

Make starch to store for later

Question 22

What is the function of the stomata

Answer 22

Holes that allow gas exchange to take place

Allows oxygen and co2 to diffuse into and out of the leaf

Question 23

Whu does the spongy mesophyll have air spaces. Hint-what does that layer need for photosynthesis

Answer 23

To allow oxygen and co2 to diffuse through the leaf

Question 24

How is meristemtissue adapted to its function

Answer 24

Contains cells that are undifferentiated to allow mitosis to happen

Question 25

A gardener decides to increase the humidity in his green house. How will this affect transpiratoon

Answer 25

It decreases because diffusion of water slows down if the leaf is already surrounded by moist air

The conc gradient is smaller so diffusison happenes more slowly

Question 26

What does the phloem vessel do

Answer 26

Transports dissolved sugars from the leaves to the rest of the plant fir immidiate use or storage-this is translocation

Question 27

How are root hair cells adapted to its function

Answer 27

They have large surface area for more absorbtion

Have lots of mitochondria for active transport

Question 28

Suggest reasons why more plants can flower in an open grass land than in a woodland

Answer 28

.can photosynthesise more
.hugher light intensity
.more rain

Question 29

How does co2 moves into the leaves

Answer 29

By diffusion through the stomata

Question 30

Explain how the change in a guard cell on a warm day help the plant survive

Answer 30

.the guard cells will close
.which will reduce the amount of water being lost

Question 31

Which part of the leaf will make the most glycose

Answer 31

Palisade mesophyll

Question 32

Describe the process that takes place in the leaf to produce oxygen

Answer 32

Photosynthesis
Requires co² and water
Produces glucose

Question 33

core practical- light intensity and photosynthesis

Answer 33

Get a set distance between alge and lamp

get 5 glass bottles and fill them up with 20 alge
and put indicator solution (hydrogen carbonate)

get another glass bottle and fill with water

cover one of those bottles in foil as darkness (put that next to the 1st bottle)

get lamp and place water between alge and lamp

wait till results

record ph change in hour

Question 34

light intensity prac- why does photosynthesis lead to the indicator solution changing colour

Answer 34

hydrogen carbonate indicator detects carbon dioxide and photosynthesis used carbon dioxide

Question 35

describe the transport of water through a plant from the roots to the atmosphere

Answer 35

by transpiration. xylem transports water from the roots to the leaves. water is then lost by evaporation through the stomata

Question 36

how is the xylem adapted to its function

Answer 36

hollow tube strengthened by lignin which gives strength and support to the plant