Introduction and Fluid Compartments Flashcards
What is negative feedback?
maintenance of homeostasis
What is positive feedback? example.
increase of activation
ovulation, gating of ion channel
What is servo-control regulation? example.
set point has been changed
fever, exercise
What is feed-forward control? example.
effector is also disturbed (thermo-, osmoregulation)
Describe the nucleus
- contains genome of the cell
- 22 pairs of autosomes and 1 pair of sex chromosomes
What cell organelle is an enzymatic machine responsible for repair and transcribing DNA?
Nucleus
Describe the mitochondria
- are composed of two membranes
- have its own DNA
- generate ATP through the oxidative phosphorilation - other biochemical processes (citric acid cycle)
What organelle is the site of sequestration of calcium ions?
mitochondria
Describe the endoplasmic reticulum
- extensive membrane network
- ribosomes, translation of mRNA
- posttranslational modification
Describe the Golgi Apparatus
- posttranslational modification
- sorts proteins and packages them for delivery
Describe the smooth ER
- no ribosomes
- synthesis of fats and lipids
- calcium ion pool
What cell organelle is responsible for the conversion of hydrophobic substances to water-soluble
Smooth ER
Describe a lysosome
- acidic interior
- serve a degradative function
Describe a proteasome
not membrane bound, degradative function
What cell organelle translates mRNA for cytosolic proteins?
free ribosomes
Describe a peroxisome
- oxidative enzymes, metabolize ethanol to acetaldehyde
Describe the cytoskeleton
- actin and intermediate filaments, microtubules
- contraction, movement, intracellular transport
Describe the plasma membrane
- separates the cell interior from the environment
- connects individual cells to the others
What is the structure of a membrane phospholipid molecule? (do drawing)
- the head is choline, polar and hydrophillic
- the tail is a non polar fatty acid chain, and hydrophobic
What are important phospholipids?
- phosphatidylcholine (outer)
- sphingomyelin (outer)
- phosphatidylethanolamin (inner)
- phosphatidylserine (inner)
- phosphatidylinositol (inner)
What is the function of sphingomyelin?
it acts as a lipid raft
What is the function of phosphatidylinositol?
signal transduction
What is an important glycolipid?
glycosylphosphatidyl-inositol (outer)
What is the function of glycosylphosphatidyl-inositol?
protein anchoring
What is the function of cholesterol? (found in inner and outer)
- membrane fluidity
- lipid raft
What are the classifications of plasma membrane proteins?
- integral membrane proteins
- lipid anchored proteins
- peripheral proteins
Name an example of integral membrane proteins.
transmembrane proteins
Name an example of lipid anchored proteins
- GPI bound proteins
- lipid modification
Name some functions of the plasma membrane proteins.
- Selective transport of molecules
- Cell recognition via surface antigens
- Cell communication (plasma membrane receptors) - Tissue organization through adhesion molecules
- Enzymatic activity
- Determination of cell shape by linking the cytoskeleton to the membrane
Draw the relationship between various body fluid compartments.
“drawing”
List examples of transcellular fluid.
- cerebrospinal fluid
- ocular fluid
- synovia (joint fluid)
- fluids in the pleural cavity
- fluids in the peritoneal cavity
