unit 3

electrical signaling

result of changes in cell membrane

paracrine

this structure uses secretion to help another cell

autocrine

these structure uses secretion to help itself

gene activatin

step 1 of protein synthesis

transcription

step 2 of protein synthesis

mRNA processing

step 3 of protein synthesis

translation

step 4 of protein synthesis

posttranslational modification

step 5 of protein synthesis

integration center

• compares output signa with setpoint to decide next steps

chemical signaling

result of cells secreting molecules into ecf

local

communication between adjacent cells

gap junctions, contact dependent signals, chemical diffusion

long distance

communication to distant parts of body

occurs in nervous/endocrine systems

gap junctions

form cytoplasmic bridges between adjacent cells

myocardial cells of heart

creates syncytium

simplest form of communication

contact dependent signals

require contact through surface molecules of cell membrane to bind with membrane protein of another

chemical diffusion

autocrine or paracrine (histamine), local communication

chemicals leave cell origin and diffuse through isf

electrical signals

travel along neuron to the end of nerve cells

neurocrine molecules

secreted at end of neuron and travel to target

neurotransmitters

neurocrine molecules that travel through extracellular space

neurohormones

neurocrine molecules that travel through blood

cytokines

communication molecules

regulatory peptides, local/long distance communication

immune response

can be released by any kind of cell

location of receptor

dependent on lipophilic vs lipophobic nature of molecules

within cell

receptor proteins bind with lipophilic signal molecules when theyre located

cholesterol

on cell membrane

receptor proteins bind with lipophobic signal molecules when theyre located

glucose, histamine

integral receptors

receptors integrated into cell membrane

receptor channels

gpc receptor

catalytic receptor

ligand gated ion channel

simplest membrane receptor

found in nerve/muscle cells

GPCRs

most commonly utilized

cytoplasmic tail

result in opening ion channel or alters enzyme activity

catalytic receptor enzymes

ligands binds and induces cellular response

catalytic integrin receptors

membrane spanning protein binding protein of extracellular matrix to anchor proteins of cytoskeleton

tissue healing

fibronectin attaching

transduction

transferring extracellular signal across membrane to alter intracellular molecules and create response

membrane proteins in our bodies

going form 1 thing to another

signaling cascades

occur once signal transduction pathway is initiated

blood clotting

amplification

occurs during transduction due to one signal molecule turning into multiple second messenger molecules

turning 1 thing into multiple

1 small ligand can have a massive affect

ligands

initiates cell response

secondary messengers

drive response

intracellular response

calcium

specificity

receptors ability to bind with a certain molecule

competition

ligands attempt to bind with a receptor challenges ligand attempting to block activity

agonist and antagonist ligands

saturation

maximum rate of protein activity within cell given proteins available

down regulation

reduction in number of receptors on cell membrane

happens with drug addicts

desensitization

modulation of receptors to decrease binding affinity and response

up regulation

increase in number of receptors on cell membrane

cellular response generation

motor proteins

enzyme activity

membrane receptors and transporters

gene activity and protein synthesis

tonic controls

variations in intensity of the agent, yet agent always remains on

regulates physiological parameters in up-down fashion

signal is resent but changes intensity

blood vessel diameter

agonists

norepinephrine (neurtransmitter)

epinephrine (neurohormone)

2 ligands induce a similar response, competitors

antagonists

do opposites effects

blocks receptor response

antagonistic controls

ability of certain factors to have opposing effects on target

uses different signals to send parameter in opposite directions

isoforms

accept the same ligand but end up with different responses

response loops in signal pathway

aid in maintaining stability of the internal environment

sensors

not the same as receptors

specialized cells

has a threshold

simple endocrine reflex

usually does not need sensors

complex neuroendocrine reflex

multiple integration centers and outputs

gets more complex

receptor

the sensor in the homeostatic reflex pathway

central and peripheral

differentiation

normal cell changes to different tissues

neural reflex

reflex is cell specific

endocrine refelx

reflex is receptor specific

neural reflex

reflex is cell to cell signals

endocrine reflex

reflex is cell blood cell signals

neural reflex

reflex action is short

endocrine reflex

reflex action is longer

neural reflex

reflex is frequency dependent

dysplasia

chronic irritation, disorganization of cells

metaplasia

adult cell changes from 1 to another, reversible

smokers throat, squamous metaplasia, trachea

GERD throat, barrett esophagus

hyperplasia

increase in number of cells, increase tissue mass, during pregnancy

tumors

abnormal new growth, no purpose, harms host, competes with host for blood and nutrients

neoplasia

uncontrolled growth of cells

swelling, tumor

not all are tumors, leukemia/multiple myeloma

epithelial

papiloma, adenoma, malignant melanoma, adenocarcinoma

malignant

metastasis occurs

necrosis is involved

is not differentiated, doesn’t belong

mesenchymal connective tissue and muscle

fibroma, fibrosarcoma, osteoma, osteosarcoma, lipoma, liposarcoma

nerve tissue

neuroma, neuroglioma, neuroblastoma, meningeal sarcoma

lymphoid tissue

lymphoma

hematopoietic tissue

leukemia, myelodysplasia, myeloproliferative syndromes

stage 0

Cancer in situ, in site

hasnt grown, benign

not malignant

stage 1

localized to primary organ

still benign

stage 2

increased risk of spread due to tumor size

still benign

stage 3

spread regionally

now malignant

stage 4

disseminated to distant sites

metastasized

size of tumor

T 0-4

lymph node involvement

N 0-4

metastasis

M1, present

M0, none

males

common cancers prostate, lung, bronchus, colon for

females

common cancers breast, lung, bronchus for

african males

heaviest cancer burden

endogenous

genetic origin

breast

prostate

ovarian

colon cancer

exogenous

environmental/external

tobacco/alcohol

viruses

chemical agents

drugs

hormones, estrogen

protooncogenes

aid in regulating cell divisions

oncogenesis

segments of DNA

transfer normal cells to malignant cells

activated by carcinogens

tumor suppressor genes

terminate oncogenes

antioncogenes

cancer

higher incidence after immunosuppression

neuromodulator

neurocrine acting mire slowly as auto or paracrine

endorphins

interleukins

help drive fever response

increase blood flow to flush out sickness

protein receptor

cell must have what to respond to signal

malignant

can not metastasis unless its

angiogensis

inducess uncontrolled vascular growth to feed malignant tumor

intravasation

invasion into blood circulation, metastasis now occurs

embolization

metastatic cells lodge at a distant site like a clot

extravasation

metastatic cells exit circulation in new tissue

paraneoplastic syndromes

remote effects of malignancy

abnormal hormone production by tumor cells

Cushing syndrome

mRNA rRNA tRNA

protein chains

morula

post fertilization zygote divides, 3-4 days becomes the

blastocyst

central cavity of morula

embryo

the cells from the inner mass are called

trophoblast

the cells from the outer layer are called