Alla

histamines

signaling molecule that induces allergy symptoms

T cells

helper cells, kill or signal additional immune response

hallmarks of the immune system

recognition and specificity, self vs. non-self discrimination and tolerance, diversity, memory, clonal expansion, specialization, regulation, homeostasis and tissue repair

phagocytes

engulf and digest (e.g., neutrophils, macrophages)

NK cells

kill infected/abnormal cells without prior antigen-specific activation

B cells

adaptive immune cells that recognize antigens and differentiate into plasma cells

bone marrow

tissue inside bones where blood cells are produced and B cells mature

thymus

where T cells mature and are selected

lymph nodes

monitor lymph, organs along lympathic vessels where lymph is filtered and immune cells encounter antigens

spleen

filters and monitors blood

antibodies

proteins that bind to antigens (aka Ig’s)

cytokines

inter-cellular signaling proteins that coordinate immune responses

V(D)J gene recombination

B/T cells rearrange pieces of DNA for antigen receptor diversity

MHCs

cell-surface proteins that display peptide fragments to T cells, signal that something is ”self”

innate immunity

rapid, broad defense

adaptive immunity

slow, specific response with memory

hematopoiesis

process of forming the cells of the immune system from self-renewing hematopoietic stem cells

neutrophil

rapid phagocytic responders

macrophage

perform phagocytosis, release cytokines, involved in tissue repair

plasma cells

produce antibodies

Peyer’s patches

collections of lymphoid tissue in the small intestine

erythrocytes

red blood cells, oxygen carriers, most abundant cells in blood

humoral immunity

adaptive immunity mediated by antibodies in bodily fluids, achieved by B cells

herd immunity

when enough people are immune that transmission reduces

active immunity

own immune system generates response, involves memory

passive immunity

receive pre-made antibodies, no memory

phagocytes, NK cells

cells involved in the innate immune system

B, T cells

cells involved in the adaptive immune system

action potential

rapid reversal of a neuron’s membrane potential caused by Na+ influx followed by K+ efflux, which propagates along the axon

CNS

part of the NS involved in information processing

efferent

“exporting”

peripheral nervous system

part of the NS that connects the CNS with the rest of the body, all nervous outside the brain/spinal cord

somatic, autonomic

parts of the PNS

somatic NS

conscious part of the PNS

autonomic NS

unconscious part of the PNS

sympathetic division

fight-or-flight part of the autonomic NS

12 thoracic + 5 lumbar

Where does the sympathetic division of the autonomic NS originate?

parasympathetic division

rest-and-digest part of the autonomic NS

cranial and sacral

Where does the parasympathetic division of the autonomic NS originate?

cerebellum

area of the brain that fine-tunes motor activity, dense and enriched with folds, contains over half the brain’s neurons

dendrites

part of the neuron that collect electrical signals

cell body

part of the neuron that integrates incoming signals and generates outgoing signals to the axon

axon

part of the neuron that passes electrical signals to the dendrites of another cell or to an effector cell

axon hillock

“trigger zone,” cone-shaped region of the soma where it connects to the axon, controls the firing of action potentials, has high density of voltage-gated Na+ channels

membrane potential

electrical voltage difference across a cell membrane created by unequal ion concentrations and selective permeability (ion gradients store potential energy for signaling!)

botulinum toxin

neurotoxic protein that blocks acetylcholine release from a neuron, suppressing muscle contraction

types of neurotransmitters

amines, purines, amino acids, peptides

acetylcholine

amino acid neurotransmitter at neuromuscular junctions, triggers voluntary muscle contractions, regulating involuntary functions like HR/digestion/sweating

neurotransmitters

chemically transmit information between cells

saltatory conduction

rapid process where nerve impulses jump from on node of Ranvier to the next along a myelinated axon, enables much faster conduction speeds

motor cortex

part of the motor system responsible for planning, initiating, directing voluntary movements

brain stem

part of the motor system responsible for basic movements and postural control

basal ganglia

part of the motor system responsible for the initiation of movement

mechanoreceptors

sensory receptors for changes in mechanical force (hearing, touch, pressure, etc.)

thermoreceptors

sensory receptors for changes in temp

chemoreceptors

sensory receptors for changes in smell, taste (chemical composition)

photoreceptors

sensory receptors in the rods/cones of the eyes

nociceptors

sensory receptors for pain

receptor potential

graded change in membrane potential produced in a sensory receptor

somatosensory cortex

part of the brain that processes sensory information, in the parietal lobe

olfactory bulb

structure just above nasal cavity at base of brain that receives signals from chemoreceptor neurons

cochlea

spiral structure that converts sound vibrations into electrical signals for the brain

vestibular hair bundles

mechanoreceptors that detect pressure variations in the cochlea, then open/close ion channels, influencing a nerve that leads to the auditory cortex

stapes, malleus, incus

smallest bones in the body that transmit and amplify vibrations to the inner ear

secretion, digestion, absorption, mobility

roles of the digestive system

salivary glands

produce saliva

liver

produces bile

gall bladder

stores and “portions out” bile

stomach

mixes and churns food with gastric juice, kills pathogens, digests proteins

duodenum

first part of small intestine

large intestine

absorbs water

small intestine

digests and absorbs

appendix

stores beneficial gut bacteria, supports immune system

rectum

stores waste material before it leaves the body

digestion process

ingestion, secretion, mixing and propulsion, digestion, absorption, defecation

H2O + electrolytes + mucus + proteins + enzymes

composition of saliva

functions of saliva

speech, chewing, swallowing, decomposition of carbs and lipids, pH regulation, protection, antimicrobial, tissue healing

medulla oblongata

What coordinates the 20-30 muscles involved in swallowing?

epiglottis

closes the trachea

mucosa, submucosa, muscularis, serosa

layers of the GI tract (in to out)

muscularis

layer of circular muscle (constricts/narrows tube to push food forward or back/forth) and longitudinal muscle (lengthens/shortens tube locally)

cephalic, gastric, intestinal

phases of digestion

hypothalamus

What regulates appetite?

pancreatic juice

protects mucus membrane in duodenum, optimizes pH

types of epithelial cells

absorptive, enteroendocrine, Goblet, Paneth, M

absorption, secretion, protection

epithelial cell functions

prodromal, retching, evacuation

phases of vomiting

migrating motor complexes (MMCs)

cleans intestines between meals, regulated by motilin

gastric juice

mucus + bicarb + gastric acid + intrinsic factor + pepsin + gastric lipase + histamine + gastrin + somatostatin

mucus

physical barrier between lumen and epithelium, alkaline

bicarbonate

buffers gastric acid to prevent epithelial damage

gastric acid (HCl)

kills bacteria, activates pepsin

intrinsic factor

enables B12 absorption

pepsin

digests proteins

gastric lipase

digests fats

histamine, gastrin

stimulate gastric acid secretion

somatostatin

inhibits gastric acid secretion

gastrin

promotes stomach mobility, stimulates production of gastric acids and enzymes

secretin

increases stimulation of bile and buffers