gjiogd Flashcards
blood osmolality
increased: drink more, release antidiuretic
decreased: not thirsty, no antidiuretic
serum osmolality tests for
hydration
hyperglycemia
hypothalamus
ethylene glycol
ethylene glycol
kidney + liver try to metabolize -> toxic metabolites -> metabolic acidosis + nephrotoxosis from oxalate forming
TREATMENT: IV (often w sodium bicarbonate) of dilated ethanol competitive inhibitor
restores hydration, electrolytes, kidney function, excretes poison
fluid
crystalloid: lots small solutes, cross wall (hypo/iso), hydrating
colloid: large, don’t cross (iso), hold fluid
ISOTONIC: same osmolality as blood eg. 0.9% NaCl
HYPOTONIC: less osmolality than blood (more solutes inside than out)
- cell burst
HYPERTONIC: more osmolality than blood (more solutes outside)
- cell shrinks
solutes
electrolytes most common
organic molecules (proteins, phospholipids, cholesterol, triglycerides) large, less, uneven between compartments
diffusion
passive
- molecules from high -> low solute concentration
- depends on size, charge, and lipid solubility
FACILITATED
- carrier protein helps
eg. glucose -> muscle/fat
DIALYSIS
- blood circulated through fake kidney-> dialysate in opposite direction -> toxins go from blood to dialysate (lower concentration)
osmosis
the movement of water from low -> high solute concentration
- semipermeable membrane
eg. water in stomach -> bloodstream
OSMOTIC PRESSURE
- water comes in because more protein interstitial
ONCOTIC PRESSURE
- pressure difference between in/out, exerted to stop when equilibrium reached
filtration
hydrostatic pressure
- fluid moves out of capillaries based on pressure gradient (heartbeat)
membrane potential
changes in ion distribution on either side of membrane -> voltage
membrane selective: Na has a harder time moving in than K
- 2 K enter, 3 Na exit
eg. muscle cell contracting.
active transport ions
Na, K, Ca2, Mg2
- need ATP + carrier
either symport (same direction) or antiport
ion concentration maintains….
irritable cells (cells that create ATP through respiration)
eg. neurons, myofibrils
cytosis
nutrients in, waste out
ENDO: into cell
phago: eats solids by phagosome
pino: liquid through membrane folds
eg. small intestine
receptor mediated: cells w/specific proteins in their membrane
- ligabands bind -> coated pit vesicle
eg. insulin
EXO: out
- vesicles in ER and golgi move to cell surface, fuse to membrane, release contents extracellularly
eg. neurons -> acetylcholine.
eg. endothelial cells -> mucus
eg. mast cells -> histamine
carbs
glucose
- makes ATP through glycosis
- excess becomes glycogen, stored in liver or becomes fat
starch: rice, nuts, grains, roots
cellulose: all veg
fat
liver can convert b/w kinds
triglycerides/neutral fats
- 2x energy of carbs/proteins
- help absorb A D E K
- insulate, protect
- energy for muscle cells, skeletal cells, hepatocytes
fatty acids:
a. saturated: only single C bonds, max H
eg. meat, dairy
b. unsaturated: double bond Cs
eg. plant oils
essential:
linoleic, linolenic, arachidonic acid
protein
amino acids (NH2, COOH, R)
- all or nothing to make a protein
essential: taurine, arginine, glycine.
- complete: meat, eggs, dairy
- complement: legumes, grain
N balance: aminos not stored, used for protein or oxidized for energy or converted to carb/fat
- + = more protein in tissue than makes ATP
- - = protein breakdown more than in tissue
- BUN test (N packaged into urea in liver, excreted by kidney)
- ruminants digest protein with microbes that improve the quality of protein
water
most important.
can also get through oxidizing protein/fat/carbs.
but this makes free radicals (A C E vitamins are antioxidants that disarm)
vitamins
co-enzymes: keys that activate an enzyme
eg. riboflavin and niacin break down glucose
all from diet except
D (skin)
A (conversion to beta carotene)
K (intestine bacteria)
- water soluble
- absorbed in GIT then peed out
eg. C, B - fat soluble
- bind to ingesta, stored in body
eg. A D E K [not stored]
minerals
macro
micro
trace
metabolism/catabolism
stage 1: GIT - hydrolysis
- protein -> amino
- carb -> glucose
- fats -> fatty acids + glycerol
stage 2: cytoplasm (anaerobic).
- pyruvic acid -> acetyl coA
stage 3: mitochondria (aerobic)
- ADP + Po4 = ATP
anabolism
uses stored energy to make new molecules
metabolic turnover: constant manufacturing of new replacement molecules
energy storage: supplied by catabolism -> released when bonds break
eg. ATP, NADH, FADH2
dehydration synthesis: 2 things bond and extra H2O created
eg. poly = mono + mono
eg. fat = glycerol + fatty
eg. protein = amino + amino
reactions
- redox: electrons removed from oxidation
- reduction: gains e-, lost O, combines with H.
- oxidation: lost e- and H, combined with O - synthesis (anabolic)
- decomposition (catabolic)
- exchange: bonds broken and made
eg. ATP transfers PO4 to glucose -> glucose-phosphate
enzyme
act upon a substrate to create a product
co-factor: non-protein that completes for binding side
eg. iron, zinc, mg, K, ca
co-enzyme: nonprotein organic co-factors, often vitamins
- temporarily/permanently binds
eg. NAD, FAD, acetyl-coA
enzyme activity factors
- enzyme concentration
- substrate concentration: levels out when saturated
- temperature: levels out when enzyme denatured
- pH: levels out at extremes (except pepsin which likes 1.5)
clinical enzymes
only found in cell, in blood if damaged
alkaline phosphatase = liver/bone
amylase = pancreas
lipase = acute pancreatitis
alanine transaminase = hepatitis
aspartate transaminase = heart
assay on isozymes to pinpoint
enzyme reversible inhibition
a. competitive
similar structure to normal substrate -> the more concentrated one winds
- reversed by increasing substrate concentration
eg. bacteria needs folic acid -> sulfanilamide resembles and competes -> folic acid stopped -> bacteria died
b. non-competitive
- no resemblance, binds elsewhere
- changes substrate’s shape so it doesn’t bind to normal substrate anymore
eg. isoleucine feedback inhibitor (end product inhibits earlier step)
enzyme irreversible inhibition
covalent bond with functional group of enzyme -> inactivates it
eg. heavy metals combine to sulfyhydrl groups and cause neurological damage, chelating agents tightly hold on
eg. penicillin inhibits enzymes (transpeptidase) bacteria needs to build cell wall
enzyme control mechanisms
zymogen: inactive precurose that is stored and released when needed
eg. prothrombin -> thrombin
genetic: adapt to environment, more enzymes made as needed
allosteric regulation: enzyme combines with modulator that either activates or inhibits -> shape changes
eg. isoleucine (modulator) binds to threonine deaminase and inhibits it -> total 5 enzyme reactions -> isoleucine levels are lowered, threonine deaminase active again -> more isoleucine made in response
