Studied by 3 people
4 types of cell communication
autocrine, juxtacrine, paracrine, endorine
autocrine
self signaling
juxtacrine
signals affect only adjacent cells
paracrine
signals diffuse to and affect nearby cells
endocrine
long distance signaling
signal transduction
reception, transduction, response
ligand
chemical messenger
reception
cell receives signal
transduction
signal travels inward
response
cell acts
ligand examples
insulin, epinephrine,
2 responses
enzyme activation, protein synthesis or both
ATP
adenosine tri-phosphate, nitrogenous base, 3 phosphate groups
(de)phospholysation
adding/removal of phosphate group
g-protein receptor
polar ligand, reception, causes conformational change, alpha sub-unit detaches for adenalyl cyclase, adelyyl cyclase converts ATP to cAMP, cAMP bonds to inactive kinase, makes them active, causes enzyme activation or TFP in nucleus
non-polar ligand
able to travel through membrane, no transduction
homeostasis
maintenance of dynamic equilibrium
endotherms
warm blooded animals
ectotherms
cold blooded
thermoregulation
radiation, evaporation, convection, conduction, metabolism
feedback mechanism
regulation system that works to return body to homeostasis stimulus --> integrater --> effector
types of feedback
positive and negative
positive feedback
amplifies the stimulus to deviate from set point to achieve goal (fever --> kill pathogen)
negative feedback
counteract the stimulus to get back to set point
standard deviation
a computed measure of how much scores vary around the mean score SD = √(Σ(x-avg)^2)/n-1
shape of standard deviation
bell shaped curve
Standard error of mean
how well the sample average reflects the true average
SEm=s/√n low = accurate
SEM bars
overlap = no statistical difference. always use 2SEM
Immune system signaling
juxtacrine
immune system function
fight pathogens, recognize harmful vs safe, get rid of malfunctioning cells
pathogen examples
bacteria, viruses, fungi, parasites
pathogen composition
releases toxins, has anti-gens (ID tags) (antibody generating)
two immune systems
innate and acquired
3 innate responses
physical, chemical, cellular
physical innate
natural microbial community, pH, hair/fur, mucus, sweat, dead skin
chemical innate
ALL LIGANDS // interferon (interferes with viral receptors), histamine (causes inflamation), pyrogen (causes fever), perforin (destroyys membrane), compliment protein (activated with antibody, releases chemicals)
Cellular defense
Nuetrofil (white blood cell, kills via phagocytosis, in large intestin), Macrophage ("big eater", can consume 100s of pathogens before death), Mast cells (cant kill instead releases histamine signal), `Natural Killer cell (releases perforin) Dendritic Cell (phagocytosis)
which cellular defenses are an antigen presenting cell (APC)
Macrophage and dedritic
acquired immune system
helper T-cells (tells cells what to do) b-lymphocytes (spotter, splits in to memory and plasma, memory remembers tag, plasma makes antibody) t-lymphocytes (killer, looks for antibody, splits into memory and cyto-toxic, memory remembers antigen and cytotoxic kills with perforin
antibody function
swarmed with antibodies = neutralization
agglutination = neutralized pathogens stick together
compliment protein activated
nervous system
paracrine signaling, brain main controller
neuron
functional unit of nervous system, gap between neurons = synapse
neuron components
soma (body), dendrites, axon (hillock), nodes, myelin sheath, axon terminal
2 types of neurotransmitter
excitatory and inhibitory
node membrane makeup
sodium/potassium pump, leaky potassium channel sodium channel activates one V=-55, potassium channel opens once V=40
how does voltage change
homeostasis = -70, stimulus (neurotransmitter) once V rises to -55, Na pump opens, when V gets to 40, K pumps opens and Na pump closes
endocrine system
sending via blood stream neural signal --> hypothalemus --> pituitary gland --> body
Note
Flashcard