cells Flashcards
what are prokaryotic cells?
do not have their genetic material enclosed in a nucleus and has no membrane bound organelles
what are eukaryotic cells?
has its genetic material located within the nucleus and has membrane bound organelles
centriole function
involved in nuclear division as they create spindle fibres which pull the chromatids apart to the opposite side of the cell
centriole structure
hollow cylinders that are made up of a ring of microtubules
mitochondria function
site of aerobic respiration
mitochondria structure
folded inner membrane = cristae
nucleus function
has a double membrane and contains the chromosomes and the nucleolus
nucleolus function
where ribosomes are made
rough endoplasmic reticulum
membrane - bound flattened sacs. Ribosomes are attached to the outer surface, proteins are made and transported from the ER to other parts of the cell
Ribosomes
made of RNA and proteins - site of protein synthesis
cell surface membrane
phospholipid bilayer
smooth endoplasmic reticulum
no ribosomes attached, makes lipids and steroids.
golgi apparatus
sacs of flattened membrane that are formed by the fusion of vesicles from ER. Modifies proteins and packages them for transport.
lysosomes
contain digestive enzymes. Breaks down dead cells/unwanted substances. Break down proteins into amino acids.
endomembrane system
- transcription of DNA to mRNA —> mRNA leaves the nucleus
- protein made on ribosomes enter rough ER
- vesicles pinched off the rough ER contain the protein
- vesicles from rough ER fuse to form the flattened sacs of the golgi apparatus
- proteins are modified within the golgi apparatus
- vesicles pinched off the the golgi apparatus contain the modified protein
- vesicles fuse with the cell surface membrane releasing protein such as extracellular enzymes
