Physio1

Connective tissue

tunica externa (outer layer)

Smooth muscle tissue

tunica media (middle layer)

Epithelial tissue

tunica intima (inner layer)

Intracellular fluid

located inside of cells

Extracellular fluid

located outside of cells

2 types of extracellular fluid

interstitial and plasma

Interstitial fluid

exists directly outside of our cells

\*\* main exchange between here

Plasma

fluid in blood containing 99% of water

Homeostasis

maintenance of constant conditions in the internal environment (temperature, volume, ECF composition); set point for all things in the body

\*\* only applies to ECF

Why does homeostasis only apply to ECF?

cells operate at their own level; The ICF of a neuron has more than the ICF of a slow twitch muscle fiber (higher ATP demand). Since they are at different content levels, they regulate themselves

All organ systems except for what function to maintain homeostasis for the body

reproductive system

3 components of homeostatic pathways

regulated variable sensors, integration center, and effectors

Regulated variable sensors

become aware of deviated levels in the body (the pancreas senses that blood glucose levels are higher)

Integration center

determines what to do about deviations from the baseline (the pancreas releases hormones (insulin) to the adipocytes and skeletal muscle cells which uptake the glucose from the bloodstream, thus lowering levels back to normal)

Effectors

what performs the act that will return to homeostasis (the muscle and fat cells that uptake the glucose; always drive the variable back to baseline)

Homeostasis always involves what kind of feedback loop?

negative, always returns to baseline

Negative feedback in homeostasis

reduces the stressor/ the output is slowed or stopped to keep the variable within normal range; ex. sweating to reduce body temperature

Negative feedback loop examples

thermoregulation, blood sugar regulation

Positive feedback loop

amplifies the output until homeostasis is reached

ex. increased contractions until the baby is out

Positive feedback loop examples

childbirth, clot formation, female menstruation

Polar molecule

molecule with an unequal distribution of charge, resulting in the molecule having a positive end and a negative end

Nonpolar molecule

molecule that shares electrons equally and does not have oppositely charged ends

When an atom becomes an ion

when a stable ion gains or loses an electron

Polar molecules interact with what

other polar molecules and ions

Non-polar molecules interact with what

other non-polar molecules

-OH

polar

-SH

polar

-COOH

acid

-NH3

base

-HPO4

polar

Carbohydrate basic composition

carbon, hydrogen, and oxygen

Monosaccharide

simplest carb, found mostly in fruit/honey, polar (-OH group)

Glucose

monosaccharide

Fructose

monosaccharide

Galactose

monosaccharide

Disaccharide

2 monosaccharides joined together via condensation

Sucrose

disaccharide

Lactose

disaccharide

Polysaccharide

most complex carb made up of 3+ monosaccharides, found in nature as a starch

Starch

polysaccharide in the form of potatoes, oats, quinoa, grains, beans, bread (most common)

Condensation

joining two monosaccharides by extracting a water

Hydrolysis

the use of water to break a polysaccharide into disaccharides and monosaccharides

Lipid basic composition

hydrogen and carbon atoms (hydrocarbons)

Triglycerides (lipid)

the type of lipid we eat (animal fat, etc.) with a glycerol back bone and fatty acids

Glycerol

The backbone of a triglyceride with 3 fatty acids attached

Fatty acid

16+ hydrocarbon repeats in the form of unsaturated or saturated

Saturated fatty acid

saturated with hydrogen and has NO double bond (no kink)

Unsaturated fatty acid

not saturated with hydrogen and has double bonds (has the kink, easy to breakdown)

Phospholipid (lipid)

composed up of hydrocarbons

polar head with a non polar tail that form the plasma membrane

Steroid (lipid)

composed up of hydrocarbons, formed from cholesterol

Amino acids

20 different types made up of 3 components: carboxyl group, amino group, side chain/R group

Proteins

sequence of amino acids

Fibrous proteins

strands that serve a structural purpose

ex. collagen

Globular

spherical shaped that serve a functional role

ex. myosin head

Nucleotide basic characteristics

phosphate group, sugar, and a base

Energy transferring nucleotides

Transfers energy within our cells ; ex. ATP, NAD, FAD

Cyclic nucleotide

form a ring with the phosphate group by binding the phosphate group to the oxygen of the sugar; Ex. cAMP and cGMP

Nucleic acid

polymer of nucleotides that store and express genetic code

DNA

2 strands of nucleotides bound together with coding existing inside of the nucleus that enables the creation of new proteins; stores genetic code (A, G, C, T)

RNA

1 strand of nucleotides made from DNA via transcription; express the genetic code (A, G, C, U)

Cholesterol in plasma membrane

breaks the rigidity of the membrane caused by the strong non-polar hydrocarbon tail bond; makes the membrane even more impermeable by adding another non-polar component

Integral membrane proteins

proteins embedded in the plasma membrane that does not leave. Some are receptors, pores/passageways, enzymes

Peripheral membrane proteins

covalently bonded to the membrane lipids/proteins to form glycolipids/glycoproteins

Peripheral membrane protein function

* form glycolax (layer that hold cells together)
* cell recognition

Cytoplasm

space inside the cell that isnt the nucleus

Cytosol

fluid inside the cell (intracellular fluid)

Rough Endoplasmic Reticulum

makes proteins; rough due to it being beaded with ribosomes which make proteins by combining amino acids

Smooth Endoplasmic Reticulum

makes lipids; this structure is specialized in some cells (this is in the liver stores detoxification enzymes that arent in any other organ)

Ribosomes

combine amino acids with coding from mRNA to make proteins

Golgi apparatus

proteins go here to be modified, packaged, and sent off to where they need to go

Mitochondria

makes ATP via oxidative phosphorylation; muscle cells and neurons are loaded with these because of their high ATP demand

Nucleus

very selective (double layer) with pores that dictate what come in and out of the cell. contains DNA and a nucleolus

Nucleolus

where rRNA is synthesized to make ribosomes; highly compartmentalized

Transcription

when the double helix of a DNA is split and 1 layer is copied. By copying 1 layer, you can make RNA

Translation

when RNA travels to the ribosomes to give them the base codes that denote the recipe (amino acid chain) to make the protein

Metabolism

the sum total of all chemical reactions that occur in cells

Anabolic

taking smaller structures to make larger structures

Catabolic

larger molecules/structures are broken down into smaller ones

Exergonic reactions

energy is released; reactions have more energy than products

Endergonic reactions

requires an input of energy since the reactants have less energy than products

exergonic-endergonic coupling

using the energy from the energy-releasing reaction to fuel the energy-deficient reaction

dephosphorylation

removing a phosphate group

phosphorylation

adding a phosphate group

Oxidation

loss of electrons

Reduction

gain of electrons

Activation energy barrier

in order for reactants to turn into products, they must cross this threshold, which stops random reactions from happening

Enzymes

increase the rate at which reactants become products by reducing the activation energy barrier

Lock and key model

enzymes have an active site that substrates bind to. The active site is shaped in a specific way to match the substrate/reactant

Factors that influence enzymatic rates

* Temperature
* pH
* Cofactors
* Coenzymes
* Saturation (concentration)
* Affinity

Temperature on enzymatic rates

can increase or decrease the enzymatic rate if it is outside of optimal range (too hot or too cold)

pH on enzymatic rate

can increase or decrease, depending on the enzyme, if it is outside of the optimal range

Cofactors

bind to the enzyme (not on the active site) and allow the enzyme to function; usually vitamins or minerals

Coenzymes

bind to the enzyme (not on the active site) and allow them to function but will participate in the chemical reaction; ex. NAD, FAD, CoA

Saturation (concentration) on enzymatic activity

an increase will result in a faster reaction rate as long as there are more enzymes with substrates attached; more substrates with less enzymes does not speed up the reaction, solve this with more enzymes

Affinity on enzymatic activity

the shape of the active site fits one substrate better than the other

Allosteric regulation

a molecule binds to an enzyme which subsequently changes the shape of its active site

Allosteric activation

increase the catalytic activity, increase the affinity

Allosteric inhibition

decrease the affinity, decrease the catalytic activity

Covalent regulation

the addition of a phosphate increases or decreases the affinity

Feedback inhibition

the products of a pathway go back into the reaction as a reactant to slow the process down; ex. ATP going back into the Krebs cycle to slow down the cycle