CELLS 3 ( cell functions & structures ) Flashcards
Ribosomes function
Site of protein synthesis
the amino acids are correctly ordered to form proteins
function of the cell wall
prevents cells from bursting due to osmotic damage causing pressure changes eg shrinking
what is a plasmid and which cell type is it found it?
circular DNA that floats free in cytoplasm in a prokaryotic cell that contains genetic code
what 2 features does prokaryotic DNA lack vs a eukaryotic cells nucleus?
- No histone proteins present (DNA not held together)
- no introns ( cells that don’t code for proteins )
what’s a nucleoid?
space in a prokaryotic cell cytoplasm where DNA is found
function of slime capsule
- makes the cell slippery so cell can’t be engulfed by white blood cells
- prevents prokaryotic cell from drying out
- surrounds cell wall
what type of ribosomes are present in a eukaryotic cell?
80s
what type of ribosomes are present in a prokaryotic cell?
70s
what cell type does not have a cell wall?
animal eukaryotic cell
what is a prokaryotic cell wall made of?
peptidoglycan
what is a plant cell wall made of?
cellulose
what is a fungal cell wall made of?
chitin
Function of a flagellum
- in prokaryotic
- hair like structure to propel the cell forward
function of a Golgi apparatus
- eukaryotic cell
- produces lysosomes
- synthesises proteins from the rough ER
- processes, packages, modifies and transports proteins & lipids
what does the smooth ER do?
synthesises and processes lipids
what does the rough ER do?
- ribosomes attached so it processes proteins for transport
Function of nucleus
- Eukaryotic
- controls cell activity
- contains genetic material and chromosomes
- nucleolus in centre, produces ribosomes
Role of the nucleolus
produces ribosomes in the centre of the nucleus
what is the plasma membrane made of?
phospholipids
function of plasma membrane
Controls movement of substances in and out of the cell
Function of the lysosomes
- Small liquid spheres surrounded by a membrane
- eukaryotic cell
- enzymes to breakdown and hydrolyse foreign matter
what do the enzymes in the lysosomes do?
breakdown and hydrolyse foreign matter in cells
3x additional organelles that plant cells have that animal don’t
chloroplasts, cell wall, large permanent vacuole
Function of large permanent vacuole
- makes cell turgid
- temporary food store for cell in cell sap (solution of salts + sugars)
- helps get rid of waste chemicals
what membrane is a large permanent vacuole surrounded by?
- tonoplast membrane.
- contains pigments, salts, sugars and wastes
Function of mitochondria
- releases energy in cellular respiration
- contains enzymes in Cristae for aerobic respiration
- generates ATP
Function of chloroplasts
- site of photosynthesis
- contain photosystems
- Contain photosynthetic pigments
- Thylakoids = LDR
- Stroma = LIR
describe nucleus structure in eukaryotic cell
- surrounded by nuclear envelope
- has nuclear pores
- centre = nucleolus ( makes ribosomes )
- contains genetic material (chromatins)
describe structure of a plasma membrane
- made of phospholipids
- phospholipid bilayer with carrier and channel proteins within it
- receptor molecules to respond to hormones
what two proteins exist within the phospholipid bilayer in the plasma membrane
carrier and channel proteins
describe structure of a mitochondria
- oval shape
- Cytoplasm (glycolysis)
- double membrane,
- Folded inner membrane called cristae (contains electron transport proteins)
- inner membrane called the matrix and contains aerobic respiration enzymes for krebs cycle, link reaction.
describe structure of a chloroplast
- surrounded by double membrane
- internal system of thylakoids that are stacked into grana
- grana linked by lamella
describe structure of a Golgi apparatus
- flattened sacs surrounded by a membrane
- Golgi vesicles off of the sacs
Are ribosomes surrounded by a membrane?
No, they’re made of proteins
