Topic 7

Question 1

Stimulus

Answer 1

causes a change in one or more homeostatic variables

Question 2

Sensor/receptor

Answer 2

How a cell or tissue detects the change

Question 3

Integrator/control center

Answer 3

processes collected by comparing to “optinmal” set-point. Decides if adjustments are needed

Question 4

Effectors (Hormones, muscles,etc.)

Answer 4

target cell for message, responds to bring homeostasis back within normal range

Question 5

Effect

Answer 5

response that opposes the effects of the stimulus

Question 6

Ligand

Answer 6

chemical message used to talk to target cells

Question 7

Lipid Derived Ligand

Answer 7

-Most are modified from cholesterol
-Examples include: testosterone and estradiol
-Hydrophobic with a long half-life
Long half-life meaning the time it takes to break down and remove half of the concentration released – needs “taxi cabs” (transport proteins) to help be moved through the blood

Question 8

Amino acid derived Ligand

Answer 8

-Most are produced from 1-2 amino acids
-Tyrosine and tryptophan
-Examples include: Epinephrine, norepinephrine, Acetycholine, and melatonin
-Hydrophilic with a short half-life
-Real life example: Adrineline rush, it only lasts seconds to milliseconds

Question 9

Peptide Ligand

Answer 9

-Shorter chains of amino acids (up to ~50 aminos long)
-built up from 1 amino acid to a chain up to 50 amino acids, all the way up to chains longer than 50 amino acids. It can have multiple chains and subunits
-Examples: Oxytoxin (love hormone) and Insulin (blood glucose control)
-Hydrophilic (bigger & water soluble)
-Souble in water, no transporter, larger and harder to break down = Intermediate half-life.

Question 10

Vesicles

Answer 10

Cellular storage/transport structure made of a bilayer phospholipids, with hydrophilic core. Used to move and store water-loving molecules. Example: most protein-based signals