EUKAROYOTIC CELLS Flashcards
what are eukaryotic cells?
they are plant cells and animal cells. these cells contain a nucleus and membrane bound organelles. they contain DNA which is linear and made of chromatin, which is stored in the nucleus, and their genes spilt from introns into exons.
what are prokaryotic cells?
they are bacteria cells which do not contain membrane bound organelles ,nucleus, chloroplasts etc. instead they contain flagella, capsule, single circular DNA molecule, plasmids and 70s ribosomes.
what does the nucleus do?
it controls the cell activities and the replication and transcription of DNA.
Function and structure of the rough endoplasmic reticulum ?
contains a folded membrane called cisternae which is a system of membrane bound flattened sacs. RER is where protein synthesis takes place as proteins are folded and processed and then transported to the golgi apparatus through the vesicles.
What are the structures that the nucleus contain and their functions?
. Nuclear envelope: contains nuclear pores which allow the movement of MRNA ( single stranded RNA which is a messenger as DNA is to large to move out of the nucleus)
. nucleoplasm: contains chromatin which is densely packed with DNA and protein which make chromosomes.
. nucleolus: make ribosomes and RNA production and it is involved in protein synthesis. Ribosomes are made in the nucleolus and sent out into the cytoplasm.
Functions and structure of the smooth endoplasmic reticulum?
contain a folded membrane called cisternae which is a system of membrane bound flattened sacs. In the SER the production, storage and processing of lipids and carbohydrates take place.
Function and structure of the Golgi apparatus ?
Golgi Apparatus is the factory part of the cells. it contains a folded membrane called cisternae from which secretary vesicles pinch off from. In the Golgi carbohydrates are added to proteins which are passed into the golgi by ribosomes and these form glycoproteins. The golgi package proteins and lipids into special membrane bound parcels known as golgi vesicles, these are then transported to the cell surface membrane of the golgi by the vesicles. The golgi also make lysozomes.
Function and structure of lysozome ?
membrane bound organelles which release hydrolytic enzymes , these hydrolyze cells and breakdown dead cells. the enzymes are also released to the outside of the cell to destroy material. they also digest worn out organelles.
Function and structure of mitochondria?
where aerobic respiration takes place and the site of ATP production. it contains a double membrane and its inner membrane is called cristae. in the middle of the mitochondria is the matrix which contain enzymes used in respiration. Mitochondria also have mitochondria DNA.
Function and structure of ribosomes?
Large ribosomes found in the Eukaryotic cells known as - 80s. Small ribosomes which are found in Prokaryotic cells known as - 70s. Ribosomes are small organelles made up of sub units of protein and RNA , it is the site of protein synthesis.
Function and structure of the Vacuole ?
Filled with fluid known as cell sap and have a single membrane called a tonoplast. The cell sap acts as temporary food storage and separated unwanted chemicals. The tonoplast maintains the cells internal pressure.
Function and structure of Chloroplasts ?
It is the site of photosynthesis and surrounded by a double membrane. in the middle of the chloroplast is a fluid filled stroma. it contains thylakoids one stack of thylakoids is known as a granum and these thylakoids and flattened sacs which increase SA for Photosyhthesis . Chloroplasts contain starch grains for energy storage and contains enzymes for Photosynthesis.
Function and structure of the cell wall?
found in plants which provide structural strength to the cell. Cell wall made up of cellulose and the cellulose polymers bond with hydrogen bonds to form microfibrils which allow the cell wall to be flexible. Fungi cells also contain cells walls however theirs is made of chitin.
Function and structure of plasma membrane ?
Controls what enters and exists the cells and membrane bound organelles. Made up of a lipid bilayer which consists of two layers of phospholipid molecules.
