Lecture 1: Homeostasis Flashcards
Which ion(s) is most abundant in the intercellular matrix?
Sodium & Chloride
Which ion(s) is most abundant in the intracellular matrix?
Potassium
Homeostasis
Maintanence of near constant/normal internal conditions
Parameters for homeostasis
Optimum
Humoral concentrations
Temperature
Partial pressures
Any stimuli that causes the loss of homeostasis
Stress
Ion(s) most abundant in extracellular fluid?
Cation - Na+
Anion - Cl-
Ion(s) most abundant in intracellular fluid?
Cation K+
Circulatory system in which information is constantly being sent to a central hub
Feedback system
Negative feedback loop
A change in parameters that causes a response in the opposite direction (negative) as the stimulus
The response reverses the change or restores homeostasis
Baroreceptors can induce which feedback system type
Negative feedback loop
Positive feedback loops
A change in parameter that causes a response in the same direction (positive) as the original stimulus
Response increases the change
Cervix dilation during labor is an example of what? And why does it work?
Positive feedback loop
Works because it has a natural end = baby is born
Why are positive feedback loops dangerous?
Because they typically have no natural end and can spiral out of control, making them dangerous and unwanted.
Lead to runaway effects
An increase in the production of TSH releasing factor results in an increase in the release of thyroid stimulating hormone, which results in the release of more thyroxine, which results in a decrease in the production of TSH releasing factor. What type of feedback system does this represent?
Negative feedback loop
Gain
The degree of efficiency to which a controlled system can maintain homeostasis
Gain equation and answer
Correction/////error
The answer is always negative
Uncontrolled system dif. 100 to 175
controlled system dif. 100 to 125
calculate gain
correction/error or uncont./control 175-125 ----------- 125-100 =50/25 = (-)2
relate cell membrane to unit membrane
all membranes have a common basic structure which is referred to as the ‘unit membrane’
what does the unit membrane consist of?
a phospholipid bilayer, with cholesterol inserted among the phospholipids
name the types of proteins associated with a cell membrane
peripheral proteins - easily removed, only connected to one side
integral proteins - embedded within membrane and cannot be removed
how are peripheral proteins attached to the cell membrane?
GPI anchoring proteins
glycophosphatidylinositol
list some functions of the cell membrane
selectivity filter intra- and extra- matrix composition maintaining homeostasis info exchange exo/endo cytosis
with what functions is clathrin associated?
endocytosis
pits coated with clathrin form vesicles
which organelles are associated with digestion within a cell?
lysosomes
contain hydrolytic enzymes at low pH
utilize H+ pump
differentiate between primary and secondary lysosomes
primary lysosomes come from the golgi
secondary lysosomes = a primary fused with a phagocytic vesicle
the RER is involved with proteins that are…..?
proteins bound for lysosomes or for secretion
what types of proteins are synthesized by free ribosomes?
proteins bound for the: cytoplasm nucleus mitochondria other cell membranes
functions of the golgi apparatus
packaging proteins for secretion
forming lysosomes
modify proteins from RER
anaerobic respiration
glycolysis
glucose —> pyruvic acid
occurs in cytoplasm of all cells
does not require oxygen
aerobic respiration
kreb’s cycle and ETC
lactate —> ATP, CO2, H2O
occurs in mitochondria
requires oxygen
what does aerobic respiration use oxygen for?
as final electron receptor in ETC
what energy system produces the greatest amount of ATP?
aerobic respiration
the three types of locomotion
ameboid mvt
cilia/flagella
microtubules
describe ameboid mvt
rolling blob
used by macrophages and other leukocytes
describe cilia/flagella mvt
are projections off of the cell membrane
fingerlike projections are used to move the cell or to move material around cell
what is the difference between cilia and flagellum?
flagella - move cell itself, only one we have is sperm
cilia - move material around cell
what type of movement is microtubules involved in?
microtubules act as a rail system
allows vesicles to transport material around cell
