4. Cell Ultrastructure Flashcards
Define limit of resolution.
The minimum distance at which two objects can be distinguished.
What is the relationship between limit of resolution and wavelength?
They’re proportional to each other, as resolution improves (limit gets reduced), wavelength decreases.
How are prokaryotes and eukaryotes different in terms of internal membranes?
Prokaryotes have no internal membranes whereas eukaryotes are compartmentalised by internal membranes.
In what way are phospholipid bilateral membranes amphipathic?
They have a hydrophilic head and hydrophobic tails.
What is the glycocalyx?
The cell coat, made of oligosaccharides and polysaccharide side chains on the outside of the plasma membrane.
What are the main functions of the plasma membrane?
Selective permeability, transport of materials along cell surface, ends and exocytosis, intercellular adhesion and recognition, and signal transduction.
Where are smooth endoplasmic reticula found?
In the liver, mammary gland, ovary, testis and adrenal glands.
Which face if the Golgi apparatus received vesicles with proteins and which has them budding off from?
The cis face receives proteins, and vesicles bud off from the trans face.
What are the functions of the Golgi apparatus?
To modify, sort, concentrate and package proteins synthesised on the rough endoplasmic reticulum.
What is the difference between primary and secondary lysosomes?
Primary lysosomes aren’t fused but secondary ones are fused.
Where are lysosomes generated?
In the Golgi apparatus.
What do lysosomes contain?
Hydrolysis enzymes.
What is the function of lysosomes?
To fuse with material that needs digesting and digest it.
Where are peroxisomes found?
In liver and kidney cells.
What is the function of peroxisomes?
To detoxify different toxins like alcohol, phenols, for mic acid and formaldehyde.
