plant tissue Flashcards
waxy cuticle
protective layer on top of leaf
prevents water from evaporating
upper epidermis
thin and transparent layer
allowed light to enter palisade mesophyll
palisade mesophyll
tightly packed with lots of chloroplasts
maximises photosynthesis
lower epidermis
guard cells and stomata
spongy mesophyll
contains air spaces
increase SA to volume ratio for diffusion of gases
guard cell
allow Co2 to diffuse in and
o2 to diffuse out
opens and closes at night / day
protects internal tissues
xylem
transports water in to lead for mesophyll cells to use in photosynthesis
phloem
transports minerals, sucrose and amino acids
photosynthesis equation
co2 + water -> glucose + oxygen
what substance strengthens xylem walls
lignin
adaptations of root hair cell
no chloroplasts
long projections
structure of xylem
made of dead cells
contains lignin
do not have pores in their end walls
hollow
does not contain cytoplasm
structure of phloem
made of living cells
have pores in their end walls
contains cytoplasm
does not contain lignin
similarities of xylem and phloem
both tubular
both made of cells
what is xylem involved in
transpiration
