Plant Adaptations

Question 1

in descending order, list out the features of a plant

Answer 1

• waxy cuticle
• upper epidermis (containing tightly packed cells)
• layer of palisade mesophyll tissue
• xylem and phloem tubes
• spongy mesophyll tissue with air spaces
• lower epidermis containing stomata
• guard cell

Question 2

why do desert plants have thick cuticles

Answer 2

to protect against excessive loss of water from transpiration

Question 3

adaptation of palisade layer

Answer 3

• has lots of chloroplast
• near the top of the leaf for more light absorption
• means higher rate of photosynthesis

Question 4

adaptation of stomata open during the day

Answer 4

allows more CO2 and water to diffuse into the plant throughout the day

Question 5

adaptation of leaf being very thin

Answer 5

CO2 doesnt have long distances to diffuse before reaching a cell that needs it

Question 6

adaptation of spongy cells creating air spaces inside the leaf

Answer 6

air spaces provide large surface area for cells to exchange gases with the air

Question 7

adaptations of manzita bushes

Answer 7

• small leaves to minimise surface area for water loss by transpiration / by evaporation
• green leaves means lots of chloroplast for more light absorption in desert sun
• thick waxy cuticle to protect against excessive water loss, as hot sun means they’re more prone to drying up

Question 8

special features of the oak tree

Answer 8

broad and disposable leaves so they can shed them to minimise water loss through transpiration

Question 9

special features of prarie grass

Answer 9

• narrow leaves to lose less water and 3.5m deep roots to absorb moisture when dry
• bright flowers attract pollenators

Question 10

special features of the water lily

Answer 10

• stomatas on upper surface of leaves as bottom is facing water
• flat leaves to maximise light exposure
• weak stems allows them to focus energy on expanding leaf network

Question 11

special features of the cactus

Answer 11

• thick fleshy stems to store water
• widespread root system collect water form a large area
• spines to minimise water loss to transpiration

Question 12

adaptation of the upper epidermis

Answer 12

transparent so that light can pass through it to the palisade layer

Question 13

adaptations of xylem and phloem vessels

Answer 13

• form a network of vascular bundles
• which provide plant with water for photosynthesis
• and takes away glucose produced
• also help support its structure

Question 14

adaptation of the lower epidermis

Answer 14

• has lots of stomata

- which let CO2 diffuse directly into the leaf

Question 15

adaptation of the spongy mesophyll tissue

Answer 15

contains air spaces which increases the rate of diffusion of gases into and out of the leaf’s cells

Question 16

why would plants in the desert have curled leaves or hairs on the surface of leaves

Answer 16

• it reduces air flow close to the leaf

- trapping water vapour near the surface and reducing diffusion from the leaf to the air

Question 17

why would a plant in the desert have fewer stomata or stomata that only open at night

Answer 17

to reduce water loss by evaporation

Question 18

why would a plant in the desert have stomata sunken in pits

Answer 18

• makes stomata lower than the surface of the leaf
• which reduces air flow close to the stomata
• this reduces water loss in the same way as curled leaves