plasma membrane:
membrane made up of a double layer of phospholipids and cholesterol and also
has proteins embedded. proteins may extend thru entire membrane or only protrude one side. some
may also have attached sugar groups. it serves as a barrier and transports substances in and out of cell.
externally facing proteins act as receptors
mitochondria: Powerhouse of the cell, organelle that is the site of ATP (energy) production;
metabolites are broken down and oxidized and used to attach phosphates to ADP molecules and make
ATP
rough ER:
sugar groups attached to proteins in cisternae; proteins boud to vesicles for transport to
the Golgi apparatus and other sites; external face synthesizes phospholipids
smooth ER:
site of lipid and steroid synthesis, lipid metabolism, and drug detox
Golgi apparatus:
packages, modifies, and segregates proteins from the cell, inclusion in
lysosomes and incorporated into the plasma membrane
Peroxisomes: enzymes detox a number of toxic substances; most important catalase breaks down
hydrogen peroxide
Micortubules: support cell and give it shape; involved in intracelular and cellular movememnts, form
centrioles and flagella
Microfilaments:
involved in muscle contraction and other types of intracellular movements, help
form cell cytoskeleton
intermediate filaments: stable cytoskeletal elements, resist mechanical forces acting on cell
centrioles:
storage for nutrients, wastes, and cell products
nuclear envelope:
to and from nucleus
chromatin:
proteins
separates nucleoplasm from the cytoplasm and regulates passage of substances
granular material visible within the nucleus; consists of DNA tightly coiled around
simple diffusion:
kinetic energy; net movement of all molecules from one are of higher
concentration to an area of lower concentration along concentration gradient
facilitated diffusion:
kinetic energy; same as simple diffusion but the diffusing substance is attached
to a lipid soluble membrane carrier protein or moves thru a membrane channel
osmosis: kinetic energy; simple diffusion of water thru a selectively permeable membrane
primary-active transport:
transport of substances against a concentration gradient; preformed
across plasma membrane by a solute pump directly using ATP hydrolysis
secondary-active transport:
co-transport of 2 solutes across membrane; energy is supplied indirectly
by ion gradient created by primary active transport; symporters move transported substances in the
same direction; antiporters move transported substances across the membrane
pinocytosis:
plasma membrane sinks beneath an external fluid droplet containing small solutes;
membrane edges fuse, forming a fluid filled vesicle
phagocytosis: "cell eating" an external particle is surrounded by a "seizing foot" and becomes enclosed
in a vesicle
exocytosis:
secretion or ejection of substances from a cell; substance is enclosed in a membranous
vesicle which fuses with the plasma membrane and ruptures, releasing substances to exterior
sodium-potassium pump:
uses an enzyme call Na+-K+ATPase; regulate the Na and K that are
inside and outside the cell; needed for excitability of cells; works continuously; releases Na out of the
cell and takes in K; need ATP
channels:
membrane
intramebranous proteins that transport substances like ions and water thru the plasma
cell-life cycle:
series of changes a celll goes thru from the time it is formed until it reproduces
interphase:
the period of the cell cycle during which the nucleus is not undergoing division, typically
occurring between mitotic or meiotic divisions
mitosis:
process by which the nucleus and duplicated chromosomes of a cell divide and are
evenly distributed, forming two daughter nuclei
cytokinesis:
RNA:
division of the cytoplasm during cell division
single stranded; can leave the cell; part of protein syntheis by forming chains of amino acids
amino acids:
consists of codons of mRNA in chains that form proteins
glycolipid:
Glycocalyx
lipids with attached sugar group found outside plasma membrane; make up the end of
primary germ layers:
make up four primary tissues
ectoderm:
forms the nervous tissue
mesoderm:
forms the muscle and connective tissue
endoderm:
forms epithelium
stratum basale: deepest epidermal layer; attached to the dermis layer, also called stratum germintivum;
highly mitotic; single row of stem cells
stratum spinosum:
several layers of cells thick, prickly cells
stratum granulosum: 3-5 cells thick, process of keratinization is beginning; keratohyaline granules in
cells help produce keratin in upper layers and lamellated granules contain water resistant glycolipid
stratum lucidum:
thin translucent layer found in thick skin like palms and heels; 2-3 cells thick of
flat clear keratinocytes
stratum corneum:
outermost layer of skin; 20-30 cells thick; provides a durable outercoat of body
that protects inner cells
dermis: strong, flexible connective tissue; papillary layer is areolar connective tissue; reticular layer is
coarse irregular dense fibrous connective tissue
hair: produced by a hair follicle consists of heavily keratinized cells; has a central medulla, cortex, and
outer cuticle, root and shaft portions
nails:
scale-like modifications of skin; nail matrix is constantly growing
rule of nines: divides body into 11 areas each counting for 9% of the body to calculate how much of
the body has been burned
first degree burns:
results in redness, swelling, and pain; tends to heal in 2-3 days without special
attention; only affects epidermis
second degree burns: affects epidermis and top half of dermis; results in blisters; skin regeneration
occurs with little to no scarring in 3-4 weeks
third degree burns:
full thickness burns; appears grey-white; cherry red or blackened; initally little to
edema; since nerve endings have been destroyed there is no pain; skin grafts usually needed
rotation:
the turning of a bone on its own axis
flexion: reduces the angle of the joint
extension:
increases the angle of the joint
abduction:
to move away from middle line of body
adduction:
to move towards middle line of body
circumduction: movement of a body part so that it outlines a cone in space
supination:
turning backward
pronation:
turning forward
dorsiflexion:
pointing outwards
plantar flexion: flexion of wrist or ankle
inversion:
foot turns medially
eversion:
sole facing laterally
protraction:
jutting out of jaw
retraction:
pulling jaw back
depression:
moving elevated body part inferiorly
opposition:
touching thumbs to tips of fingers of same hand
plane joints:
allow only short axial gliding movements
pivot joint:
uniaxial rotation of one bone across its own axis
condyloid joint: allows flexion and dorsiflexion, adduction and abduction and circumduction
saddle joints:
found in fingers
muscle contraction:
calcium ions released after a nerve signal and binds with troponin and triggers
tropomyosin to shift, exposing the actin filaments active sites. myosin binds with available sites of actin
forming cross-bridges. myosin heads release ADP and used phosphate from ATP used as energy and
moves toward midpoint sarcomere, pulling actin with it (power-stroke) Z discs pulled together and H
zones get smaller, sarcomeres shorten
fetal blood flow thru heart valves:
placenta delivers oxygen rich blood to the veins leading to the
heart and throughout the fetal body; arteries carry oxygen low blood out of the body to the placenta
diastole:
period of cardiac cycle when either artia or ventricles are resting
systole:
period of cardiac cycle when either atria or ventricles are contracting
purkinje fibers:
modified ventricular muscle fibers of the conduction system of the heart
SA node:
specialized myocardial cells in the wall of the right atrium; pacemaker of the heart
AV node:
specialized mass of conducting cells located at the atrioventricular junction of the heart
bundle of his: bundle of specialized fibers that conduct impulses from the AV node to the right and left
ventricles; also called atrioventricular bundle
P wave:
QRS:
atrial depolarization
ventricular depolarization and atrial re-polarization
ST interval:
entire ventricles are depolarized
T wave:
ventricular re-polarization begins
Neutrophils:
phagocytize bacteria
Platelets:
fragments of megakaryocytes; needed in coagulation of blood
Eosinophils:
kill parasitic worms; complex role in allergy and asthma
Basophils:
release histamine and other mediators of inflammation; contain herapin, an
anticoagulant
Lymphocytes: mount immune response by direct cell attack or via antibodies
Monocytes:
phagocytosis; develop into macrophages in the tissues
Erythropoietin: EPO; hormone released from the kidneys to stimulate RBC production
Albumin:
60% of plasma proteins; produced by liver; main contributor to osmotic pressure
Globulins:
30% of plasma proteins; alpha and beta- bind to ions, lipids, and fat soluble vitamins;
gamma- antibodies released by plasma cells during immune response
Fibrinogen:
4% of plasma proteins; produced by liver, forms threads of blood clots
Coagulation: phase 1- prothrombin activator formed; phase 2- prothrombin activator converts
prothrombin into thrombin (enzyme); phase 3- thrombin catalyzes fibrinogen molecules into a fibrin
mesh that traps blood cells and effectively seals the hole until blood vessel is repaired
blood pressure maintenance: depends on cardiac output, peripheral resistance, and blood volume,
vasomotor center regulates cardiac output and blood vessel diameter; baroreceptors detect changes in
blood vessel diameter
physiological response to exercise:
increases respiratory pump, activity of muscular pump, and
sympathetic venoconstriction- increases venous return- increases end diastolic volume- increases stroke
volume- increases cardiac output
hyperventilation:
needs
an increased depth and rate of breathing greater than demanded by the body
hypoventilation:
Reduction in the volume of air that enters the lung for gas exchange; oxygen
exchange insufficient to meet metabolic demands of the body
PCO2: if levels rise the CO2 accumulates in the brain and results in carbonic acid dissociation; the H+
that are released stimulate the chemoreceptors in the brain stem and increase the depth and rate of
breath
control of respiration: nerves in the medulla and pons, medulla contains rhythm generating and
integrative center; pons smooths out transitions between inspiration and expiration
blood pH:
pH rises
if CO2 levels are high then the pH of the blood drops; if the CO2 levels are low then the
PO2: O2 sensors that cause the respiratory centers to increase ventilation; significant drops in PO2
needed to increase ventilation
salivary glands: parotid, submandibular, sublingual; secretes saliva (salivary amylase, water,
electrolytes, mucin, metabolic wastes)
stomach:
different layers of muscle used to digest food; rugae helps grind up food; gastrin
released to increase HCl secretion; histamine released to activate parietal cells to release HCl; serotonin
released to contract stomach muscles; somatostatin released to inhibit gastric secretions of all products;
vasoactive intestinal peptide (VIP) released to inhibit acid secretion; pepsin used to digest proteins
gallbladder:
thin-walled muscular sac on the ventral surface of the liver; stores and concentrates bile
by absorbing its water and ions; releases bile via the cystic duct that flows into the bile duct
bile:
yellow-green solution containing bile salts, bilirubin, cholesterol, fats, phospholipids, and
electrolytes
pancreas:
under stomach, spleen connected to it; pancreatic islets secrete insulin and glucagon;
acini secrete pancreatic juice; zymogen contain digestive enzymes; pancreatic juice neutralizes chyme
and has electrolytes, amylase, lipases, nucleases, proteases
CCK (cholecystokinin): potentiates secretin's actions on organs; also involved in anxiety, pain, memory;
inhibits appetite
enzymes that digest proteins: pepsin (stomach); trypsin, chymotrypsin, carboxypeptidase (pancreatic
proteases); aminopeptidases, carboxypeptidases, dipeptidases (brush border enzymes)
enzymes that digest nucleic acids:
pancreatic ribonucleases and deoxyribonuclease
liver: lobed accessory organ that overlies the stomach; produces bile to help digest fats and serves
other metabolic and regulatory functions
hypothalamus: region of the diencephalon forming the floor of the third ventricle of the brain
posterior pituitary gland:
hypothalamic-hypophyseal tract; oxytocin and ADH
anterior pituitary gland:
hypophyseal portal system; GH, TSH, ACTH, FSH, LH, PRL
growth hormone-GH: produced by somatrophs in the anterior pituitary; stimulates liver, skeletal
muscle, bone and carilage to produce insulin-like growth factors, but targets bone and skeletal muscle
thyroid-stimulating hormone-TSH:
and secretory activity of the thyroid
produced in anterior pituitary; stimulates normal development
andernocorticotropic hormone- ACTH: produced by anterior pituitary; stimulates adrenal cortex to
release corticosteroids
follicle-stimulating hormone-FSH:
luteinizing hormone-LH:
hormones
produced by anterior pituitary; stimulates gamete production
produced by anterior pituitary; promotes production of gonadal
prolactin-PRL: produced by anterior pituitary; stimulates milk production
oxytocin:
stored in posterior pituitary; stimulates contractions during childbirth and also triggers
milk ejection in women producing milk, plays role in sexual arousal and orgasms
antidiuretic hormone-ADH:
stored in posterior pituitary; also known as vasopressin; responds to
changes in solute concentration in the blood
thyroid hormone-TH: 2 related compounds T4 (thyroxine) and T3 (triiodothyronine); produced by
thyroid gland; major metabolic hormone; maintains BP, regulates tissue growth, develops skeletal and
nervous system, reproductive capabilities
calcitonin:
produced in C cells of thyroid gland; inhibits osteoclast activity and release of Ca2+ from
bone; stimulates Ca2+ uptake and incorporation into bone matrix
parathyroid hormone-PTH:
released by parathyroid gland; stimulates osteoclasts to digest bone
matrix; enhances reabsorption of Ca2+ and secretion of phosphate by the kidneys; promotes activation
of vitamin D
aldosterone: mineralocorticoid released by the adrenal cortex; stimulates Na+ reabsorption and
water retention by the kidneys
cortisol:
glucocorticoid released by adrenal cortex; keeps blood sugar levels relatively constant;
maintains BP by increasing action of vasoconstrictors; causes gluconeogenesis; promotes rise in blood
glucose, fatty acids, and amino acids
androgens (estrogen and testosterone):
gonadocorticoids released by adrenal cortex;
contributes to onset of puberty, appearance of sex characteristics, and sex drive
epinephrine and norepinephrine:
secreted by adrenal medulla; cause blood glucose levels to rise,
blood vessels to constrict, heart to beat faster, blood to be diverted to the brain, heart, and skeletal
muscle; epinephrine stimulates metabolic activities, bronchial dilation, and blood flow to skeletal
muscles
melatonin:
derived from serotonin and released from pineal gland; affects timing of sexual
maturation and puberty, day/night cycles, physiological processes that show rhythmic variations
glucagon:
released from pancreas; major target is liver; promotes glycogenolysis, gluconeogenesis,
and release of glucose to the blood
insulin: released by pancreas; lowers blood glucose levels; enhances glucose transport into fat and
muscle cells; part of neural development, learning and memory; inhibits glycogeolysis and
gluconeogenesis; increases cellular respiration; glycogenesis; converts glucose to fat
progesterone: maturation of female organs, appearance of female secondary sex characteristics, and
breast development and cyclic changes in uterus mucosa
atrial natriuretic peptide-ANP: released by heart; reduces BP, BV, and Na+ concentration in blood 176.
Erythropoietin- released by kidneys; signals production of RBCs
renin: released by kidneys; initiates renin-angiotensin mechanism
cholecalciferol: released by skin; precursor to vitamin D
lepton: released by adipose tissue; involved in appetite control and stimulates increased energy
expenditure
thymus:
releases thymulin, thymopoietins, and thymosins; all involved in normal development of
T lymphocytes in immune response
osteocalcin:
released by osteoblasts; produces pancreatic beta cells to divide and secrete more
insulin, improving glucose handling and reducing body fat
kidney: removes toxins, metabolic wastes, and excess ions from the blood; regulated blood volume,
chemical composition and pH; gluconeogenesis
mechanism of urine formation: 1. glomerular filtration; 2. tubular reabsorption (returns all glucose,
amino acids, 99% of water, salt and other components to the blood; 3. tubular secretion (reverse of
reabsorption, selective addition to urine
nephron:
structural and functional unit of kidney; consists of glomerulus and renal tubule
urine: 95% water, 5% solutes, Na+, K+, PO4(3-), SO4(2-), Ca2+, Mg2+, HCO3-, urea, uric acid, and
creatinine
hormonal regulation of male repo. Function:
GnRH stimulates FSH and LH; FSH stimulates release of
androgen-binding protein (ABP) which makes spermatogenic cell receptive to testosterone, LH
stimulates release of testosterone which triggers spermatogenesis
hormonal regulation of female repo. Function: GnRH stimulates FSH and LH which trigger growth of
several follicles and estrogen release, estrogen inhibits LH and FSH; sudden LH surge at day 14 which
triggers ovulation and transforms ruptured follicle into corpus luteum which forms inhibin,
progesterone, and estrogen; inhibits LH and FSH release, ends luteal activity and inhibits follicle
development; days 26-28 corpus luteum degenerates and ovarian hormone levels drop sharply
menstruation: days 1-5 menstrual phase: ovarian hormones are at lowest, gonadotropins beginning to
rise, stratum functionalis is shed and menstrual flow occurs; days 6-14 proliferative phase: estrogen
levels prompt generation of new functional layer, increases synthesis of progesterone receptors in the
endothelium, glands enlarge and spiral arteries increase in #; days 15-28 secretory phase: endothelium
prepares for implantation of embryo, progesterone causes spiral arteries to form functional layer
conception:
the developing of offspring
implantation: completed by the 12th day after ovulation; after conception, cell divides after 36 hours,
by 72 hours 16 or more cells, at day 3 or 4 forms a blastocyst that floats for 2-3 days, implantation
begins 6-7 days after ovulation and is complete by the 12th day
stages of labor: dilation stage: 6-12 hours, longest part of labor, initial weak contractions, cervix opens
10cm, amnion ruptures and releases amniotic fluid; expulsion stage: strong contractions every 2-3
minutes about 1 min long, urge to push increases, crowning occurs, delivery of infant; placental stage:
strong contractions continue and cause detachment of placenta and compression of uterine blood
vessels, delivery of afterbirth occurs about 30 min after birth, all placental fragments must be removed
to prevent postpartum bleeding
central nervous system- CNS: brain and spinal cord; integrating and command center of the nervous
system; interprets sensory input and dictates motor responses based on reflexes, current conditions,
and past experiences
peripheral nervous system-PNS: the part of the nervous system outside of the CNS; mainly consists of
the nerves that extend from the brain and spinal cord; 2 main divisions: sensory and motor
spinal nerves: carry impulses to and from the spinal cord
cranial nerves: carry impulses to and from the brain
sensory division:
part of the PNS; afferent; consists of nerve fibers that convey impulses to the
CNS from sensory receptors throughout the body
motor division: part of the CNS; efferent; transmits impulses from the CNS to effector organs (muscles
and glands); has to major parts: somatic nervous system and autonomic nervous system
somatic nervous system : composed of somatic motor nerves fibers that conduct impulses from the CNS
to skeletal muscles; often referred to as voluntary nervous system
autonomic nervous system-ANS:
consists of visceral motor nerve fibers that regulate activity of
smooth and cardiac muscles and glands; also referred to as the involuntary nervous system; has 2
functioning subdivisions: parasympathetic division and sympathetic division
sympathetic division: prepares body for activity or to cope with some stressor; fight or flight
response; increased heart rate
parasympathetic division:
decreased heart rate
oversees digestion, elimination, and glandular function; rest and digest;
multipolar neuron:
have 3 or more processes, one axon and the rest dendrites; most common
neuron in human body, 99% of neurons; major neuron type in CNS
bipolar neuron: have 2 processes and axon and a dendrite that extend from opposite side of the cell
body; rare neurons found in special sense organs
unipolar neuron:
single short process that emerges from cell body and divides like a T, a central
process that enters the CNS and a peripheral process that is associated with a sensory receptor; found
chiefly in the ganglia in the PNS where they function as sensory neurons
reflex arc:
reflexes that occur over neural pathways; rapid automatic responses to stimuli
acetocholine-Ach:
first neurotransmitter to be identified; released at neuromuscular junctions;
synthesized from acetic acid and choline by the enzyme family cholinesterase; enables muscle action,
learning and memory
fight or flight response: body provides energy, reflexes, and strength needed to respond to stressors;
epinephrine (adrenaline) released, preps body for quick action by triggering: increased breathing to
increase O2 levels, increased heartbeats to increase blood flow, muscles tense up for quick movement,
pupils dilate and increase light intake for sensitive vision, decreased digestion, and increased blood
glucose for increase energy in body
myelin sheath: fatty insulating sheath that surrounds all but smallest nerve fibers; protects and
electrically insulates fibers and increases speed of impulse transmission
astrocyte:
a type of CNS supporting cell; assists in exchanges between capillaries and neurons
ependymal cells:
cord
a type of CNS supporting cell; lines the central cavities of the brain and spinal
microglia:
a type of CNS supporting cell; can transform into phagocytes in the areas of neural
damage or inflammation
oligodendrites: a type of CNS supporting cell that composes myelin sheaths
satelites cells: a type of supporting cell of the PNS; surround neuron cell bodies located in PNS; assists
in exchange between capillaries and neurons
schwann cells: a type of supporting cell of the PNS; forms myelin sheaths and is vital to peripheral
nerve fiber regeneration
synapse: functional junction between 2 neurons or a neuron and an effector cell
dopamine:
influences movement, learning, attention, and emotion; "feeling good"
neurotransmitter
serotonin:
affects mood, hunger, sleep, and arousal
GABA (gamma-aminobutyric acid):
control
a major inhibitory neurotransmitter; results in impaired motor
Glutamine:
a major excitatory neurotransmitter; involved in memory and learning
Endorphins:
natural opiates; pain perception; inhibit pain
Tachykinins:
mediates pain transmission in PNS; also involved in respiratory and cardiovascular
controls and mood
Somatostatin: often released with GABA; gut-brain peptide hormone; inhibits growth hormone release
Adenosine:
caffeine, tea, and chocolate stimulate by blocking adenosine receptors; may be involved
in sleep-wake cycle and terminating seizures; dilates arterioles, increasing blood flow to heart and other
organs
neurotransmitter receptors:
either channel-linked receptors or G-protein linked
action potential:
large transient depolarization event, including polarity reversal that is
conducted along the membrane of a muscle cell or nerve fiber
depolarization: Na+ flows into the cell
repolarization: K+ flows out of the cell
hyperpolarization:
resting state:
caused by K+ continuing to leave the cell
when no ions are moving in or out of cell
diencephalon thalamus: sensory impulses ascending to sensory cortex inputs subcortical motor cortex,
impulses from lower centers; hypothalamus: important ANS control center, water balance, regulates
thirst, hunger, body temp, gastrointestinal activity, and anterior pituitary gland activity; and
epithalamus: pineal gland extends from posterior border
brain stem:
midbrain: visual and auditory reflex centers, subcortical motor center, pain suppression;
pons: conduction area, regulates respiration; medulla oblongata: regulates respiratory rhythm, heart
rate, BP, cough, sneeze, vomit, swallow centers in medulla
cerebellum:
frontal: reasoning, planning, problem solving, parts of speech, movement, and emotion;
parietal: movement, orientation, recognition, perception of stimuli; occipital: visual processing;
temporal: perception and recognition of auditory stimuli, memory, and speech
chemoreceptor:
receptor sensitive to various chemicals in solution
mechanoreceptor:
muscle contraction
receptor sensitive to mechanical pressure such as touch, sounds, or exerted by
nociceptor:
receptor sensitive to potentially damaging stimuli that result in pain
osmoreceptor: structure sensitive to osmotic pressure or concentration of solution
photoreceptor: specialized receptor cells that respond to light energy; rods and cones
retina: neural layer of the eyeball; contains photoreceptors
lens: biconvex, transparent, flexible, elastic and avascular; allows precise focusing of light on the
retina; cells of lens differentiate into lens fibers that form the bulk of the lens
depth perception:
both eyes view the same image from slightly different angles; depth perception
results from cortical fusion of the slightly different images
pharyngotympanic tube:
connects the middle ear to the nasopharynx; equalizes pressure in the
middle ear cavity with the external air pressure
ear bones:
malleus, incus, and stapes; transmit vibratory motion of the eardrum to the oval
window; causes amplified sound
bony labyrinth: tortuous channels in the temporal bone; vestible, semicircular canals, and cochlea
vestibule:
central egg-shaped cavity of the bony labyrinth; saccule is continuous with the cochlear
duct; utricle is continuous with the semicircular canals; house equilibrium receptor regions; responds to
gravity and changes in the position of the head
semicircular canals:
3 canals that each define 2/3 of a circle; membranous semicircular ducts line
each canal and communicate with the utricle; ampulla of each canal houses equilibrium receptor region
called the crista ampullaris; receptors respond to angular movements of the head
cochlea:
spiral, conical, bony chamber; extends from the vestible; coils around bony pillar;
contains the cochlear duct, which houses the spiral organ of Corti and ends at cochlear apex
agglutination: clump of foreign cells induced by cross-linking of antigen-antibody complex
antibody:
protein molecule released by plasma cell (daughter cell of activated B cell) that binds
specifically to antigen; immunoglobulin
antigen:
substance tor part of a substance recognized as foreign by immune system, activates
immune system, reacts with immune cells
autoimmunity: product of antibodies or effector T cells that attack a person's own tissue
cell-mediated immunity:
immunity conferred by activated T cells which directly kill infected or
cancerous body cells or cells of foreign grafts and release chemicals that regulate immune response
clonal selection:
cytokinesis:
system
B or T cells activated by binding with antigen
small proteins that act as chemical messengers between various parts of the immune
cytotoxic T cells:
effector T cell that directly kills foreign cells, cancer cells, or virus-infected cells
by inducing apoptosis
helper T cells: orchestrates cellular immunity by direct contact with other immune cells and releasing
chemicals called cytokines, also helps to mediate humoral response by interacting with B cells
humoral immunity:
fluids
immunity conferred by antibodies present in blood plasma and other body
immune system:
their entry into body
a functional system whose components attack foreign substances or prevent
killer T cell:
apoptosis
effector cell that directly kills foreign, cancer, or virus-infected body cells by inducing
Treg cells:
population of T cells (CD4) that suppress immune response
T cells: lymphocytes mediate cellular immunity; mature in thymus
B cells: oversee humoral humoral immunity; differentiate into antibody-producing plasma cells; mature
in red bone marrow
antibody structure:
T or Y shaped monomer of 4 looping linked polypeptide chains; 2 identical H
chains and 2 identical L chains
IgM:
first antibody released; agglutinating agent; fixes and activates complement
IgA:
in mucus and other secretions; helps prevent entry of pathogens
IgD:
attached to surface of B cells ; B cell receptor
IgG:
75-85% of antibodies in plasma; secondary and late primary responses; crosses placental barrier
IgE:
active in some allergies and parasitic infections; causes mast cells and basophils to release
histamine
specific immunity:
takes longer to react
adaptive defense; 3rd line of defense; attacks particular foreign substances;
non-specific immunity: innate defense; 1st and 2nd defense; first line is external body membranes;
second is antimicrobial proteins, phagocytes and other body cells; inhibit spread of invaders;
inflammation is its most important response
inflammatory response:
triggered whenever body tissues are injured by physical trauma, intense
heat, irritating chemicals, or infection. prevents spread of damaging agents; disposes of cell debris and
pathogens; sets stage for repair
complement fixation: main antibody defense against antigens; several antibodies bind close together
in cellular antigen; complement binding sites trigger complement fixation into cell surface; complement
triggers cell lysis, amplifies inflammatory response, opsonsization, enlists more defensive agents