Leaf Structure Flashcards
The leaf structure…
the structure of a leaf in which is able to complete its full purpose
waxy cuticle…
waterproof layer that coats the outside of the leaf – it prevents the leaf from losing water, but does not block sunlight from getting in
epidermis…
thin membrane (skin) that holds the leaf together. It is transparent so that sunlight can pass through.
palisade layer (palisade mesophyll)…
upper part of leaf where most of the photosynthesis takes place, because this is the part of the plant/leaf that gets the most sunlight.
It is made of palisade cells that contain lots of chloroplasts so that they can absorb as much sunlight as possible to maximise photosynthesis.
spongy mesophyll…
lower part of the leaf and contains lots of air spaces.
This allows air to diffuse inside the leaf so that all the cells can get the carbon dioxide that they need for photosynthesis
stomata (plural) or …
stoma (singular)
tiny pores (holes) in the epidermis of the leaf, they are opened and closed by a pair of guard cells.
The stomata open to allow carbon dioxide to diffuse into the leaf and oxygen to diffuse out, but close when necessary to prevent too much water from being lost
more stomata in the lower epidermis than the upper epidermis because less water will be lost from the bottom of the leaf than the top
leaf vein…
carry water, food and minerals to the parts of the plant where they are needed
made up of two types of vessel (xylem and phloem) that run from the roots, through the stem and then branch out through the leaves and the rest of the plant
xylem vessels carry water and minerals from the roots (where they were absorbed from the soil) to the parts of the plant that need them (the leaves need water for photosynthesis and to help keep their shape).
The phloem vessels carry the glucose (food) that is made in the leaves to the parts of the plant that need it
transpiration…
