The extracellular compartment is composed of what two things?
2. interstitial fluid
The liquid of the blood
fluid around cells inside of tissue
random molecular motion
the movement from high concentration to low concentration. Involves a gradient
What types of substances can diffuse across the plasma membrane
1. Hydrophobic, small non-polar molecules (O2, N2, steriods)
2. small neutral molecules with polar covalent bonds (CO2, Ethanol, Urea)
3. Water thru aquaporins
net diffusion across a semipermable membrane
What type of molecules use osmosis?
polar such as glucose, sucrose
carrier proteins used by large molecules to cross a membrane
Lignand Binding site
very specific binding site used by carrier to cross membrance
use carrier proteins to cross membrane
ions use to diffuse thru PM; very specific
What are the three forms of channels?
mechnical gated and ligand gated
physical force required to open
ligand must bind to the binding site for gate to open
Electrical stimulus open and close gate
What is Fick's law
rate of diffusion= (temp* surface area*change in concentration)/molecular weight*distance
What are the two conditions of osmosis?
1. Must have a concentration gradient
2. Membrane relatively impermable to the solute
solutes cannot pass thru the plasma membrane
A hydrostatic pressure caused by a difference in the amounts of solutes between solutions that are separated by a semi-permeable membrane.
two solutions with the same osmolality
osmolality of one solutions is greater than the other
What are the two definitions of tonicity?
1. effect of the solution on osmotic movement of H2O
2. how a solution effects the tone of a cell (flaccid or turgid)
Same concentration of solute inside and outside of a cell
Lower concentration on solutes outside of the cell than inside
Lower concentration of solute inside the cell than ouside.
What are the two charactersitics for facilitated diffusion?
1. Specificity-"lock and key" ligand binding site
2. Saturation- rate of diffusion increases until all of the carrier proteins are active. Once all are active increase in ligands has NO effect on rate
requires ATP directly or indirectly because of transport against the gradient.
What are the two types of active transport?
1. Primary- requires direct energy
2. Secondary- indirectly use energy
How do primary transport work?
Use carrier protein with a ligand binding site. ATP binds and is hydrolyzed to ADP+Pi. Pi "P" the carrier protein so that their is a change in conformation. This cause the ligand to be transferred into the cell. The releasing of Pi cause protein to go back to orginal conformation
What is an important carrier protein pump?
Na+ / K+ pump
secondary coupled transport in the same direction
secondary coupled transport in opposite directions
Describe Secondary Transport
requires a membrane potential created with a primary AT pump (Na/K/H). involves the movement of something downhill with something uphill.
Layer of cells that covers the body surface; on the inner surface of body cavitie;s and lining of hollow organs
Epithelium the lines the capillaries, arteries, and veins.
movement across the epithelium
movement twice across the epithelium.
substance goes thru cells (very specific)
movement of substances between cells. (not very specific)
How is paracellular transport blocked
junctional complexes which remove space from between cells (desmosomes, tight junctions, and adherens junctions)
Substances packaged in vesicles to be moved out of a cell
substance packaged on the plasma memebrane to form vesicles to move substance in.
Receptor mediated endocytosis
more specifc. membrane doesn't fold in unitl certain receptor bind
the charge across the plasma membrane. inside is more negative than outside
What is the membrane potential necessary for
action and graded potentials
What contributes to a cells membrane potential?
Na/K pumps and other fixed ions in the cell
charge that you get across the membrane, if is is only permable to one ion
What is most important for equilibrium potential?
What is the Nernst equation used for?
determining equilibium potential
Resting membrane potential
potential across the pm in a normal situation (i.e when it is not condicuting an impluse.
What two things does resting potentail depend on?
1. concentration gradient
2. permability to that ion
What are the two types of local signaling?
What are the two types of cell signaling
2. long distance
organ release a paracrine factor that acts on a cell in the same organ
involves neurons the synapt with another cell either another neuron of an effector cell
glands release a hormone into the blood stream to transport to a target organ
What three place are endocrine receptors located
cytoplams, nucleus, and pm
The central nervous system is composed of?
brain and spinal cord
The peripherial ns is composed of?
cranial and spinal nerves and their branches
functional unit; generates electorchemical impulses (action of graded potentials);specialized
support neurons b maintianing the proper environment
concentration of RERs in the nucleus of a neuron
provide receptive area which generates graded potentials
The dendrites and _____ generate graded potentials?
conduct action potentials
generated action potentials
branches at the the end of an axon
What are the two ways for neurotransmitter to get to teledendria?
1. axoplasmic flow
2. axonal transport
faster more specific; can either be orthograde or retrograde; use motor protein to transport vesicle down a microtubule
movement in one direction very slow and non-specific
What are the two ways to classify neurons?
function and stucture
mostly axons with myelin sheaths
cell body neurons and dendrites
groupings of neuron cell bodies in the PNS
Where do motor neurons have there cell bodies?
in the grey matter of the CNS
Sensory Neurons (afferent)
carry sensory info towars CNS
Associate neurons (interneuron)
synapes with sensory and motor neurons
What are the four fn neuron types of the PNS?
somatic sensory/motor, viseral sensory/motor
Where do Somatic and Viseral sensory neurons have their cell bodies?
in dorsal root ganglion
Where do Somatic and Viseral motor neurons have their cell bodies?
in grey matter
What are the two ways too synapse?
electrical or chemical
presynaptic neuron synapes on dendrite of post synaptic neuron
presynaptic neuron synapes on cell body of post synaptic neuron
presynaptic neuron synapes on axon of post synaptic neuron
involves gap junctions wich are made out of connexin proteins
what gap junctions are made of
The first cell is always a neuron which synape with an effector
Describe the process of release NT.
An action potential move down the axon to the terminal bouton where Ca volataged gated channels are located. The Channels open and Ca flows in to bind with Synaptotagmin to form a complex. This complex act on the SNARE fusion complex which triggers exocytosis of the NT vesicles.
What kind of ion channels are located on the post-synaptic cell?
What are the two ways that a chemical gated ion channel on the post-synaptic cell can be opened/closed?
either by the direct binding of the ligand to the receptor or by the receptor acting as a 2nd messenger(G-protein).
When ions flow into the post-syn cell how do they change the membrane potential?