Cells Flashcards
What is the nucleolus?
A dense aggregation of rRNA in the nucleus that produces rRNA and ribosomes to build proteins.
What is the function of the rough endoplasmic reticulum?
To produce secreted and membrane-bound proteins.
What type of cell might have a lot of RER?
A plasma cell, to secrete antibodies.
What is the function of smooth endoplasmic reticulum?
To synthesise lipid substances.
What cell might have a lot of SER?
An enterocyte or hepatocyte for synthesising lipoproteins. A steroid hormone secreting cell, that undergoes intense (high ATP requirement) synthesis of lipids.
What is the function of the sarcoplasmic reticulum?
Store calcium ions (intake through phosolambam) then release the calcium after activation of the ryanodine receptor (which is coupled to dihydropyridine receptor).
What is the function of secretory granules?
To store substances until the signal comes for them to be secreted.
They allow the cell to carry out regulated secretion, e.g a hormone secreting cell from the pituitary, or a mast cell secreting histamine (constitutive secretion).
Name the water compartments in the body.
Intracellular water.
Extracellular water, which includes:
1) Interstitial compartment (contains interstitial fluid)
2) Intravascular compartment (blood)
3) Transcellular (fluid doesn’t normally accumulate in large amounts e.g CSF, synovial fluid, pleural and peritoneal cavities).
What is the function of peroxisomes?
To digest toxic peroxides, metabolise fatty acids and other metabolites e.g alcohol.
What is the function of an endosome?
Vesicles that is formed from the plasma membrane and transports extra cellular material into the cell.
What is the function of the smooth endoplasmic reticulum?
Synthesises lipids and steroid hormones, involved in carbohydrate metabolism, calcium concentrations (e.g sarcoplasmic reticulum), drug detoxification.
What is the first component of the Krebs cycle?
Citric acid.
What is the product for aerobic glycolysis, and what is the product of anaerobic glycolysis?
Aerobic glycolysis = pyruvate
Anaerobic glycolysis = lactate
How do prions propagate in the host?
Induce the conversion of endogenous proteins into prion proteins.
What is a retrovirus?
A virus with an RNA genome that replicates via a DNA intermediate using reverse transcriptase.