Basics(module1)

human physiology

study of processes and function in living organism

order of physiology, smallest to biggest

cells → tissues → organs → organ systems

homeostasis

maintaining stable internal environment is key for optimal function

components for homeostasis

receptor, control center, effector

receptor

detects imbalance and sends signal(ex. thermoreceptors: temp is too high)

control center

receives signal and decides what to do to restore balance(ex. nervous system)

effector

receive command/info and completes action to restore balance(ex. sweat glands release fluid and blood vessels dilate)

extracellular fluid

1/3 of total body fluid; OUTSIDE cells

intracellular fluid

2/3 of total fluid; INSIDE cells`

fluid imbalance

ECF or ICF gain or lose fluid

cell membrane

maintains fluid balance, permeable barrier, selects ions & nutrients for cell function

physical characteristics of cell membrane

phospholipid bilayer(polar heads & fatty acid tails); has proteins

functions of cell membrane proteins

structure, communication(cell to cell), signaling, maintenance(ICF & ECF), identification(tells other cells what they are)

Cell junction

join plasma membranes of adjacent cells and aid& inhibit molecule movement

Tight junction

seals neighboring cells together like zip block

Desmosomes

anchors adjacent cells together

gap junction

connects cells by hollow cylinders

Endocytosis

plasma membrane forms vesicle to bring in substance; phagocytosis, pinocytosis, receptor mediated endocytosisp

phagosytosis

for large particles/microorganisms; in specialized cells

pinocytosis

fluid-phase/small particles endocytosis; non specific

receptor mediated endocytosis

receptors bind to specific molecules(humoral immunity naive to activated b cell)

simple diffusion

hig to low concentration; no atp

facilitated diffusion

high to low with transport protein; no atp; leakage channel(always open); voltage gated(membrane potential threshold); ligand gated(molecule bind to receptor)

filtration

high to low pressure; no atp; water and solutes; in kidneys