Plant Cell Structure and Function

grana

embedded stacked, disk-like plates which are the site of photosynthetic reactions

chitin

material that the cell wall of fungi is made of instead of cellulose like plants, bacteria, and some protists

chlorophyll

pigment molecules that give the choloroplast it's green color; loss of it in the fall reveals the red and yellow carotenoid pigments that are also in the choloroplasts

difference between animal and plant cells

plant cells have the additional organelles of a cell wall, chloroplasts, and a central vacuole; the cell membrane functions the same but may have channels to connect the cytoplasm of connecting cells in plants

turgor pressure

pushes the plasma membrane against the cell wall of plant, bacteria, and fungi cells as well as those protist cells which have cell walls. This pressure, turgidity, is caused by the osmotic flow of water from area of low solute concentration outside of the cell into the cell's vacuole, which has a higher solute concentration. Healthy plant cells are turgid and plants rely on turgidity to maintain rigidity.

central vacuole

takes up much of the volume of a plant cell' a membrane-bound fluid-filled space which stores water and soluble nutrients for the plant's use; tendency to absorb water gives plant cells their rigid shape (turgidity)

stroma

the body of the chloroplast

chloroplasts

the site of photosynthesis; found in plant cells and some protists; stroma (body) contain grana

cell wall

wall made of cellulose and lignin that encloses the cell membrane providing structural support and protection; allows plant cells to store water under relatively high concentration; allows substances to pass through it easily so transport into and out of the cell still need to be regulated by the cell membrane (bacteria also have a cell wall)