A&P Flashcards
3 study techniques
notecards, practice exams
knowledge is more lasting if learning is
effortful and more difficult
anatomy is
study of organs
physiology is
study of organ functions
levels of organization in body
cells, tissue, organ, organ system, organism
cells are
smallest unit of life
composed of cell membrane, cytoplasm, organelles
types of tissue
connective, epithelial, neurons, muscle
cellular differentiation
unspecialized cell specialized for a certain purpose
components of extracellular fluid
proteins, polysaccharides, minerals, water, nutrients
the organ systems are
circulatory, digestive, endocrine, immune, integumentary, nervous, musculoskeletal, reproductive, respiratory, urinary
why do larger organisms need organ systems
can’t use diffusion to get nutrients and gases
the systems transport nutrients, waste products, gases
specialized cells become resistant to change- homeostasis
control systems to maintain homeostasis
negative feedback, positive feedback, feed foreward, resetting the set point
steady state
energy used to maintain
equilibrium
no energy required
set-point
variable kept at
negative feedback
opposite forces used to counteract change
ex. insulin to gluose
positive feedback
accelerates change
ex. blood clotting, partution
resetting the set-point
changes point variable set at
extracellular variables in body must be stable at all times
false
reflexes can be feedforward
true
organ system that has the smallest role in homeostais
reproductive
organ systems that have role in homeostasis
digestive, lymphatic, reproductive, urinary
which feedback most common in body
negative
cholesterol in plasma membrane tends to ______ membrane fluidity
decrease
single protein can bind to many different ligands
true
ligand-protein interactions can be covalent
false
negative feedback loop
afferent pathway efferent pathway
stimulus –> receptor—————————-> integrating center—————-> effector—–>response and back to stimulus
main effector for a reflex
muscles and glands
hormone: travel and communication
in blood
long distance
neurotransmitter: travel and communication
nerves
long distance
paracrine agents: travel and communication
acts on nearby cells
autocrine agents: travel and communication
blood, long distance
acts on same cell or same type
desmosome has
cadherins protein
desmosomes connect
cells to each other
cadherins connect to
cytosolic proteins
cytoskeleton and to cadherins on adjacent cells
tight junctions
acts as permeability barrier
gap junctions
pore between cells that lets ions pass through
has connexins protein
hemidesmosome proteins
integrin and fibronectin
chemical specificity
protein-binding site to specific ligands
determines type of chemical that’s bounded, shape
saturation
fraction of total binding sites that are occupied at a given time
affinity
strength of ligand-protein binding
competition
compete for binding site if more than one ligand can bind
cooperativity
change in conformation of one subunit of a protein can change the conformation of other subunits of the protein
equation for net flux
J=PA(Co-Ci)
flux = permeability surface area (conc outside- conc inside)
primary use of ATP
to phosphorylate proteins
how do small, polar chemical species, ions or water, get across plasma membrane
polar species can diffuse through using channels
how do non-polar molecules, steroid hormones, get across plasma membrane
simple diffuse through membrane
coenzyme substrates are used how
one enzyme uses coenzyme to convert another substrate into a product, in the process of the coenzyme substrate into a product. second enzyme converts coenzyme substrate back into the substrate the first enzyme used
factors that determine net flux
conc diff, temp, surface area, mass of diffusing substance, solvent solute, membrane nature
double enzyme concentration on rxn rate by substrate
doubles rxn rate
increase affinity for substrate on rate of rxn by substrate conc
initial increase, then reaches max
3 ways of gating an ion channel
ligand, voltage, mechanically
what is a ligand-gated ion channel
chemical messenger protein conformationally change shape
voltage-gated ion channel
changes in electrically charge across membrane
mechanically-gated ion channel
membrane is stretched/less stretched pull on ions channel
4 factors determine rate of transport of solutes using facilitated diffusion
conc gradient, rate of transport, percent sat, number transporters
steps of Na/K pump cycle
K dissociates and Na binds to pump
conf change cause pump to autophosphorylate
conf change in pump causes binding sites to face outside of cell and cause protein to lose affinity for Na and gain affinity for K
Na dissociates and K binds to pump
conf change cause pump to dephosphorylate
conf change causes binding sites to face inside cell
conf change also causes protein to lose affinity for K and gain affinity for Na
normal osmolarity of body
285-295 mOsm
exocytosis
moving substance out of cell by fusing a vesicle containing the substance with the plasma membrane
endocytosis
invagination of plasma membrane
fluid-endocytosis
non specific of anything dissolved in extracellular fluid
3 types of endocytosis
phagocytosis, pinocytosis, receptor-mediated
phagocytosis
eating cells
take debris, bacteria, pathogens
receptor-mediated
bring in specific large molecules into cell
most specific
why are epithelial cells are polar
have diff proteins in apical compared to basolateral membrane
intracellular
within the cell
intercellular
between cells
signal transduction
what happens in a cell between the binding of a ligand to a receptor and the final response in the cell
agonist
drug that can bind to a receptor and trigger signal transduction
antagonist
inhibit receptors, signal transduction, wrong conf change
receptor signaling pathway that that involves a cascade of phosphorylations
receptor tyrosine kinase
enzyme that converts cAMP into AMP, inactivating it
cAMP phosphodiesterase
2 receptors that are themselves enzymes
receptor tyrosine kinase
guanylyl cyclase receptor
substrate and products catalyzed by guanylyl cyclase
GTP to cGMP and 2Pi
advantage of having so many steps in signal transduction pathway
allows for amplification of the response
Gs protein-coupled receptor
1st messenger binds to G protein coupled receptor GPCR
conf change in GPCR
conf change in alpha subunit of g-protein
alpha sub loses affinity for GDP
GDP dissociates from alpha sub
conf change in alpha sub
alpha sub loses affinity for beta/gamma sub and GPCR
dissociates
alpha sub binds to adenylyl cyclase
conf change in AC
activates AC
AC converts ATP to cAMP
increase cAMP in cytosol
cAMP binds to protein kinase A
conf change in PKA
activates PKA
PKA phosphorylates proteins
Most intercellular messengers bind to
membrane-bound receptors
Intracellular receptors are transcription factors.
False
Ion channel receptors are
ligand-gated ion channels
What effect does the alpha subunit of the Gi protein have on adenylyl cyclase?
decrease its activity
There are no active transport mechanisms for water.
True
Water moves from areas of
low osmolarity to high osmolarity
If a cell swells, it is in
a hypotonic solution
The higher the osmotic pressure, the
higher the solute concentration
The sodium-potassium pump is in __________ membrane of epithelial cells.
the basolateral
If a cell crenates, it is in
a hypertonic solution
If the volume of the cell does not change, the cell is in
an isotonic solution
There is a maximum rate of flux of solutes using a transporter.
True
Substances are usually actively transported across both the apical and basolateral membrane across an epithelial layer.
False
What ion is most commonly used in secondary active transport to move another chemical against its concentration gradient
sodium
Other than sodium and potassium, what two other ions are primarily regulated by pumps?
calcium
hydrogen
At diffusion equilibrium, all diffusion stops.
False
At absolute zero, there would be no diffusion.
True
Which causes a bigger conformational change in a protein?
Covalent modulation
The net flux of a permeable solute across a membrane is constant until diffusion equilibrium is reached.
False
The charge inside a resting cell is ____________ compared to the outside of the cell.
Negative
