cell organelles Flashcards
(24 cards)
Name three organelles involved in protein synthesis and describe their roles.
Ribosomes: synthesize proteins from mRNA
Rough endoplasmic reticulum: folds and transports proteins
Golgi apparatus: modifies and packages proteins into vesicles
Describe the role of the Golgi apparatus in the cell.
modifies proteins and packages them into vesicles for secretion
why do muscle cells usually have so much mitocondria
muscle cells have high energy demand and mitocondria produce ATP by aerobic respiration
Suggest one advantage of having organelles in a eukaryotic cell.
to allow compatmentation of reactions
Describe how the structure of the RER is related to its function.
the RER has ribosomes on its surface for protein synthesis
it has a system of membranes to transport proteins
State two features of a prokaryotic cell that are not found in a eukaryotic cell.
circular strand of DNA petidoglycan cell wall
Describe the role of plasmids in prokaryotic cells.
contain genes that aid survival like genes that code for antibiotic resistance
what is the prokaryotic cell wall made out of
peptidoglycan
Explain how a prokaryotic cell divides
circular strands of DNA replicate. membranes form between DNA
Give two differences between prokaryotic and eukaryotic ribosomes.
prokaryotic ribosomes are smaller (70s) while eukaryotic ribosomes are bigger (80s)
Describe how the DNA of a prokaryotic cell is different from that of a eukaryotic cell.
DNA in prokaryotes is cirular and not associated with histones while DNA in eukaryotes is linear and associated with histones
how is protein transported around the cell from RER to golgi
amino acids are turned into proteins by the RER then transported by vesicles to the golgi aparatus where the protein is modified and packaged into secretery vesicles
Describe the route that a protein takes from its synthesis to secretion from a cell.
✅ Model Answer:
mRNA is transcribed in the nucleus and leaves via a nuclear pore.
mRNA binds to a ribosome on the RER, and the protein is synthesised.
The protein enters the RER, where it is folded and modified.
It is transported in a vesicle to the Golgi apparatus.
The Golgi modifies the protein and packages it into a vesicle, which fuses with the membrane to release the protein by exocytosis.
🟢 Mark Scheme Breakdown:
1 mark: mRNA transcription & nuclear pore
1 mark: Ribosome on RER synthesises protein
1 mark: Protein folded/modified in RER
1 mark: Golgi further modifies/sorts
1 mark: Vesicle transport and exocytosis
What is the role of the Golgi apparatus in protein transport?
The Golgi apparatus modifies and packages proteins into vesicles for transport.
🟢 Mark scheme:
1 mark for modification
1 mark for packaging into vesicles
Nucleus
where genetic information is found within a cell
nucleolus
where ribosomes are mad e
RER
where proteins from ribosomes are folded
ribosomes
the site of protein synthesis
cell membrane
a phospholipid bilayer containing proteins and other molecules making it partially permiable
golgi aparatus
where proteins are packaged in vesicles and modified
SER
where lipids and steroids are made
lysosome
where digestive enzymes are found. involved in the break down of unwanted subcellular structures
what happens to lysosomes once there content is digested
lysosome fuses with the cell membrane and then its digested content leaves by exocytosis
II what subcellular structure is this and what does it do
involved in spindle formation centrole
