Gas Exchange in Plants

Question 1

What are the parts of a plant that is dicotylodenous?

Answer 1

waxy cuticle - long thin line
square thins - palisade (photosynthesis)
circles - spongy mesophyll
tube thin - luner epidermis
stomata = gap between two guard cells
circle thin at end of tube - guard cell

Question 2

What is gas exchange in dicotyledonous plants?

Answer 2

mesophyll is where gas exchange of co2 for photosynthesis happens - which is spongy - large surface area

gasses diffuse in / out

guard cells can open or close to reduce water loss

Question 3

What are parts of xerophytic plants?

Answer 3

stomata sunken in pits - dots
thick waxy cuticle - lines

circuit looking lines - hairs

Question 4

What is gas exchange in xerophytic plants?

Answer 4

curled leaf, stomata sunken in pits and hairs on epiderrmis are all adapations

water vapour builds up and decreases the water diffusion gradient

thick waxy cuticle reduces evaporation

fewer stomata

Question 5

Why does the stomata close to save water?

Answer 5

plant has lots of water - cells are turgid
plant cells lose water - cells are flaccid
flaccid guard cells close stomata