Ch 5 Flashcards
Mass balance definition
steady state of everything
homeostasis defnition
the ability to cope with external variability by keeping their internal environment relatively stable
homeostasis falls within _____, not an absolute number
a range
mass balance in the body
everything ingested must have an equal secretion
clearance definition
rate at which a molecule disappears from the body
- how long it takes for the body to rid of a particular item
homeostasis vs equilibrium
chemical and electrical - more homeostasis due to disequilibrium
osmosis - equilibrium
Intracellular fluid composition
K+ and large anions/proteins
composition of plasma
Na+, Cl-, large anion/proteins
composition of interstitial fluid
Na+, Cl-, some HCO3-
does facilitated diffusion require ATP
no, that why it’s diffusion
properties of diffusion
-passive
-high conc to low conc
-net movement until conc is equal
-rapid over short distances
-directly related to temp
-inversely related to molecular size
-in open system or across a partition
functions of membrane proteins
-structure
-enzymes
-receptors
transporters
structural protein function
-connect membrane to cytoskeleton
-create cell junctions to hold cells together
-attach cells to ECM
examples of ligands for receptors proteins
-chemical
-hormone
-electrolyte
channel protein properties
-regulates size and charge
-continuous
-fast
-general
carrier protein properties
-regulates substrates
-not continuous
-slow
-specific
facilitate diffusion by use of ______
carrier protein
two types of active transport
-primary uses ATP for energy
-secondary uses potential energy
ATP is necessary to carry substrate _____ the concentration gradient
against
properties of NaK ATPase
3 sodium out
2 potassium in
uses 30% of all ATP produced by cell
aspects of carrier-mediated transport
-specific
-competitive
-saturated
example of secondary active transport
sodium glucose L transporter
______ functions as competition for glucose transporter
galactose
______ functions as a competetive inhibitor
maltose
what would happen to glucose transport rates when maltose is present
flatline
rate of transport is dependent on
-substrate concentration
-number of carrier molecules
forms of vesicular transport
-phagocytosis
-endocytosis
-exocytosis
does vesicular transport use ATP
yes
phagocytosis definition
the cell engulfs bacterium or other particles into phagosome; pushes cell membrane
endocytosis properties
-membrane surface indents and forms vesicle
-active process that can be nonselective(pinocytosis) or highly selective
-receptor-mediated uses clathrin-coated pits
-smaller than phagosomes
ratio of ICF to ECF
2:1
ratio of plasma and IF in ECF
1:3
osmolarity describes
the number of particles in solution
osmosis
movement of water across a membrane in response to a solute concentration gradient
travels from _____ osmolarity to _____
low to high
tonicity depends on ______ solutes only
nonpenetrating
the electrical gradient between ECF and ICF is called
resting membrane potential
which ions affect resting membrane potential the most
sodium and large anions inside the cell
factors influencing cell membrane potential
-concentration gradients of ions
-permeability of the membrane to those ions
normal resting membrane potential
-70 mV
