Introduction and Fluid Compartments

Question 1

What is negative feedback?

Answer 1

maintenance of homeostasis

Question 2

What is positive feedback? example.

Answer 2

increase of activation

ovulation, gating of ion channel

Question 3

What is servo-control regulation? example.

Answer 3

set point has been changed

fever, exercise

Question 4

What is feed-forward control? example.

Answer 4

effector is also disturbed (thermo-, osmoregulation)

Question 5

Describe the nucleus

Answer 5

• contains genome of the cell

- 22 pairs of autosomes and 1 pair of sex chromosomes

Question 6

What cell organelle is an enzymatic machine responsible for repair and transcribing DNA?

Answer 6

Nucleus

Question 7

Describe the mitochondria

Answer 7

• are composed of two membranes
• have its own DNA
• generate ATP through the oxidative phosphorilation - other biochemical processes (citric acid cycle)

Question 8

What organelle is the site of sequestration of calcium ions?

Answer 8

mitochondria

Question 9

Describe the endoplasmic reticulum

Answer 9

• extensive membrane network
• ribosomes, translation of mRNA
• posttranslational modification

Question 10

Describe the Golgi Apparatus

Answer 10

• posttranslational modification

- sorts proteins and packages them for delivery

Question 11

Describe the smooth ER

Answer 11

• no ribosomes
• synthesis of fats and lipids
• calcium ion pool

Question 12

What cell organelle is responsible for the conversion of hydrophobic substances to water-soluble

Answer 12

Smooth ER

Question 13

Describe a lysosome

Answer 13

• acidic interior

- serve a degradative function

Question 14

Describe a proteasome

Answer 14

not membrane bound, degradative function

Question 15

What cell organelle translates mRNA for cytosolic proteins?

Answer 15

free ribosomes

Question 16

Describe a peroxisome

Answer 16

• oxidative enzymes, metabolize ethanol to acetaldehyde

Question 17

Describe the cytoskeleton

Answer 17

• actin and intermediate filaments, microtubules

- contraction, movement, intracellular transport

Question 18

Describe the plasma membrane

Answer 18

• separates the cell interior from the environment

- connects individual cells to the others

Question 19

What is the structure of a membrane phospholipid molecule? (do drawing)

Answer 19

• the head is choline, polar and hydrophillic

- the tail is a non polar fatty acid chain, and hydrophobic

Question 20

What are important phospholipids?

Answer 20

• phosphatidylcholine (outer)
• sphingomyelin (outer)
• phosphatidylethanolamin (inner)
• phosphatidylserine (inner)
• phosphatidylinositol (inner)

Question 21

What is the function of sphingomyelin?

Answer 21

it acts as a lipid raft

Question 22

What is the function of phosphatidylinositol?

Answer 22

signal transduction

Question 23

What is an important glycolipid?

Answer 23

glycosylphosphatidyl-inositol (outer)

Question 24

What is the function of glycosylphosphatidyl-inositol?

Answer 24

protein anchoring

Question 25

What is the function of cholesterol? (found in inner and outer)

Answer 25

• membrane fluidity

- lipid raft

Question 26

What are the classifications of plasma membrane proteins?

Answer 26

• integral membrane proteins
• lipid anchored proteins
• peripheral proteins

Question 27

Name an example of integral membrane proteins.

Answer 27

transmembrane proteins

Question 28

Name an example of lipid anchored proteins

Answer 28

• GPI bound proteins

- lipid modification

Question 29

Name some functions of the plasma membrane proteins.

Answer 29

• 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

Question 30

Draw the relationship between various body fluid compartments.

Answer 30

“drawing”

Question 31

List examples of transcellular fluid.

Answer 31

• cerebrospinal fluid
• ocular fluid
• synovia (joint fluid)
• fluids in the pleural cavity
• fluids in the peritoneal cavity