Internal plant structure Flashcards
What is the upper epidermis?
The transparent, outer layer of cells on the upper side of a leaf which allows sunlight to penetrate through to the photosynthetic cells, such as the palisade mesophyll, beneath.
What and where is the palisade mesophyll?
The palisade mesophyll are elongated and cylindrical cells that contain many chloroplasts in order to absorb as much light as possible. They are found directly beneath the upper epidermis.
What and where is the spongy mesophyll?
The spongy mesophyll are irregularly organised calls that sit below the palisade mesophyll and allows for the interchange of gases that are needed for photosynthesis
How do gases enter the leaf?
Gases such as carbon dioxide, water vapour and oxygen enter and exit through small pores in the leaf called ‘stomata’
What is the main vein in the leaf called?
The midrib.
What is inside the midrib?
Inside the midrib is both the xylem and phloem.
What controls the opening of the stomata? How?
The guard cells. When the guard cells fill with water, they bend outwards and open the stoma, closing when all water has gone through.
