Full Length #2 Flashcards
(157 cards)
what does active transport mean?
moving against a gradient
primary active transport
directly uses a source of chemical energy (ex. ATP) to move molecules across a membrane against their gradient
ex: sodium-potassium pump
secondary active transport
uses an electrochemical gradient (generated by active transport) as an energy source to move molecules against their gradient
-does not directly require a chemical source of energy
passive transport
does not require the cell to expend any energy
-substance diffusing down its concentration gradient across a membrane
what type of molecules have trouble crossing the plasma membrane?
polar and charged molecules
-polar molecules can easily interact with the outer face of the membrane, where the negatively charge head groups are found (ex: water molecules)
facilitated diffusion
molecules diffuse across the plasma membrane with assistance from membrane proteins, such as channels and carriers
exocytosis
a vesicle fuses with the cell membrane and expels its contents
What is the correct path of the circulatory system which describes the passage of a blood clot originating in the left leg?
vena cava -> right atrium -> right ventricle -> lungs -> left atrium -> left ventricle -> aorta
which heart valves are NOT actively closed by the contraction of muscular structure?
semilunar valves
what valves ARE actively closed by the contraction of muscular structure?
mitral (left atrioventricular)
atrioventricular
tricuspid (right atrioventricular)
At the instant following the second heart sound, which valves are open?
all valves are closed?
Rank the blood vessels in order of their average pressure, from highest to lowest
aorta > artery > arteriole > capillary > venule > vein
what layer of the heart would be most immediately susceptible to infections caused by bacteria in the blood?
endocardium
what vessels carry deoxygenated blood away from the heart?
pulmonary artery only
what kind of cells can usually diffuse across cell membranes?
small or non-polar or preferably both
what is the role of competitive inhibition?
bind reversibly to the active cite
- since reversible inhibition can be overcome by adding more substrate, Vmax remains the same
- increases kM
if an amino acid is at its isoelectric point, what does it exist as?
a zwitterion
with positive and negative charges that cancel each other out
for a female to be exhibiting x linked recessive disorders, what kind of chromosomes mush she have?
must have two copies of a defective gene
one on each x chromosome
autosomal recessive disorder
require the presence of two defective genes in order for that disorder to be expressed
amino acids with acidic R groups
glutamic acid, aspartic acid
amino acids with basic R groups
histidine, arginine, and lysine
what is the only way to increase the amount of free glutamate in a food source?
protein degradation
what does passive transport include?
diffusion, facilitated diffusion, and osmosis
facilitated diffusion
molecules diffuse across the plasma membrane with assistance from membrane proteins (channels or carriers)