Plants and organs

Question 1

Epidermal tissue definition

Answer 1

Upper most layer on a leaf
It is
Thin 
Waxy cuticle 
Minimised amount of water lost through evaporation

Question 2

Palisade mesophyll

Answer 2

Next layer down after the epidermal tissue
Responsible for most of photosynthesis
Made up of tightly packed cells with large numbers of chloroplasts

Question 3

Spongy mesophyll

Answer 3

Lots of air sacs with air pockets

Gases can diffuse freely within

Question 4

Xylem

Answer 4

Tubes that transport water and minerals form the roots up the plant
Called transpiration

Question 5

Phloem

Answer 5

Made from living cells
Responsible for dissolving sugars made from photosynthesis
Moves it from the leaves to rest of the plant
Moves substances both up and down

Question 6

Meristems

Answer 6

Found at tips of the root
Made of stem cells
Can be turned into any cell needed

Question 7

What is transpiration

Answer 7

Movement of water in a plant

Question 8

How does light intensity change the speed of transpiration

Answer 8

When light levels drop plants are unable to photosynthesise due to no co2 being needed the plant closes its stomata reduces the amount of water going out the plant

Question 9

How does temperature change the speed of transpiration

Answer 9

Warmer the water molecules inside the plant the more energy the more likely the water is to leave the plants

Question 10

How does air flow change the speed of transpiration

Answer 10

On a windy day quicker the wind quicker the water leaves the surroundings increasing the concentration gradient from the inside to the outside
Higher the gradient the quicker it diffuses out

Question 11

How does humidity affect the concentration gradient

Answer 11

The concentration gradient of a humid day the amount of water outside the leaf will be around the same as inside the lease and so less transpiration occurs

Question 12

Signs of a disease in a plant

Answer 12

Growth stunted
Leaves discoloured 
Covered with spots 
Rotting or decay 
Growths
Leaves and stems abnormally shaped
Plant discoloured 
High number of pests present

Question 13

Physical adaptations to deter pathogens

Answer 13

Plant cell walls made of cellulose
Upper surface have a thick waxy cuticle
Trees have bark

Question 14

Chemical adaptations deter pathogens

Answer 14

Able to secrete antibacterial chemicals

Poisonous qualities

Question 15

Mechanical adaptations to deter pathogens

Answer 15

Tough hairs
Thorns
Leaves curl when touched
Mimicking colours of poisonous plants