B1.2.2 Organelle Structure and Function Flashcards
What is the nuclear membrane?
Double membrane that controls entry/exit of materials to and from the nucleus.
What are nuclear pores?
Holes in the nuclear membrane that allow mRNA and ribosomes to exit.
What is the nucleoplasm?
Jelly-like material that makes up the bulk of a nucleus.
What is the nucleolus?
Small spherical region in a nucleus that contains ribosomal RNA (rRNA) and manufactures ribosomes.
What is chromatin?
An uncondensed complex of DNA and protein.
What does chromatin condense into prior to cell division?
Chromosomes
What is the function of a mitochondrion?
The site of cellular respiration.
In which eukaryotic cell would you not find a nucleus and why?
Red blood cells
To give more room to carry oxygen
Which cells contain many mitochondria?
Metabolically active cells such as:
Muscle cells
Intestinal epithelial cells
Sperm cells
Why is the rough endoplasmic reticulum described as rough?
It is ‘studded’ with ribosomes.
How does the structure of the rough endoplasmic reticulum relate to its function?
- Folds provide a large surface area for protein synthesis.
- Cisternae provide a pathway for transport of proteins.
- Can form vesicles to allow proteins to exit.
What is the function of the Golgi apparatus?
- Adds carbohydrates to proteins to form glycoproteins.
- Forms lysosomes.
- Transports and modifies stored lipids.
- Produces secretory enzymes e.g. in pancreatic or epithelial cells.
- Secretes carbohydrates for cell walls.
What is the function of the smooth endoplasmic reticulum?
- Synthesise, store and transportation of lipids.
- Synthesise, store and transportation of carbohydrates.
- Detoxification of harmful substances.
Ribosomes are made from 2 parts. What are these parts called?
Large subunit
Small subunit
