Intro and BIochemistry

what are the levels of structural organization of the human body

chemical, cell, tissue organ, organ system, organism

interaction of atoms and molecuels

chemical level

functional unit of life

cell level

group of similar cells and the materials surrounding them that perform a function

tissue level

one or more tissue functioning together

organ level

group of organs functioning together

organ system

any living thing

organism

why are no two humans exactly alike

anatomically they have a variable number of organs and organ locations and physiologically they vary in age, sex, diet, weight, physical activity, etc

what are the characteristics of life

organization, metabolism, responsiveness, growth, development, and reproduction

what are the two subunits of development

differentiation (change from general to specific) and morphogenesis (change in shape of tissues and organs)

self-regulating process where biological systems maintain internal stability while adjusting to changing external conditions

homeostasis

the ideal normal value of a variable that the body tries to maintain so it fluctuates around it

set point

what are the components of a feedback system

stimulus, receptor, control center, effector, response

occurs when a change is sensed and a mechanism is activated to reverse it to return conditions to normal

negative feedback

what are examples of negative feedback

human thermoregulation, blood pressure, and pH

if blood temperature gets too hot, what happens

vasodilation in skin leading to sweating

if blood temp is too cold what occurs

vasoconstriction in skin and shivering

loop that amplifies or increases a change until a specific event is completed; useful when rapid completion of a process is needed and causes change in the same direction

positive feedback

what are examples of positive feedback

childbirth, blood clotting, protein digestion, generation of nerve signals

explains how cells generate energy, communicate, and maintain homeostasis

biochemistry

anything that occupies space and has mass; ex. cells, tissues, water, proteins

matter

the amount of matter in an object; remains constant despite gravity changes

mass

the gravitational force acting on an object of a given mass: changes with gravity

weight

what identifies an element and is the number of protons in an element

atomic number

how many elements are found in the body

24

how many elements make of 98.5% of human body weight

6

what are the six elements that primarily make up humans

oxygen, carbon, hydrogen, calcium, phosphorous, nitrogen

elements that differ in their number of neutrons which increases their weight

isotopes

how do isotopes of the same element compare to each other

all chemically similar due to same valence electrons but some are very unstable and have different physical behavior

unstable isotopes due to too many neutrons and destructively decay to create stable versions by releasing radiation

radioisotopes

why are isotopes important

medicine, research, and tracing metabolic pathways

why are radioisotopes important

diagnostic imaging (PET scans) and cancer treatments

time needed for 50% to decay

physical half-life of radioisotopes

time for 50% to disappear from the body and is affected by how well the body can break down and clear it

biological half-life

atom that carries a charge due to an unegual number of protons and electrons

ions

transfer of electrons from one atom to another to increase the stability of the valence shell

ionization

make up the bodies internal electrical system and are salts that ionize (break apart) in water to form body fluids; can conduct electricity

electrolytes

what are major ions in the body

sodium, potassium, calcium, chloride, and bicarbonate

what is the importance of electrolytes

chemical reactivity, osmotic effects to influence water movement, and electrical effects on nerve and muscle tissue

examples of a few common electrical imbalances

hypokalemia causing muscle cramps (low K+), hypocalcemia causing brittle bones, and hypercalcemia causing stones, bones, groans, and psychiatric overtones

particle with an unpaired electron that is good in moderation for some natural uses but can cause tissue damage if too much

free radicals

substances physically but not chemically combined

mixture

about how much body weight does water represent depending on certain variables

50-75%

what are the factors of water that make it important

high heat capacity and effective coolant to stabilize internal temp, universal solvent, transports substances, and participates in chemical reactions

polar molecule that dissolves easily in water

hydrophilic molecules

solutes are dissolved evenly into a solvent, creating a transparent and homogeneous mixture where solute can pass through cell membranes

solutions

mixture of proteins and water that result in a cloudy substance and can change from liquid to gel state within and between cells; particles too large to pass through cell membranes

colloids

proton donor

acid

proton acceptor

base

the concentration of H+ ions in solution

pH

why are bases worse to be exposed to

they do not weaken as rapidly and instead penetrate deeper

why is an acid-base balance in the body important

pH changes will affect absorption of different materials

resists pH changes

buffer system

most important buffer in blodd plasma where the lungs remove CO2 and kidneys excrete or reabsorb HCO3-; failure leads to acidosis or alkalosis

bicarb buffer system

all the chemical reactions of the body

metabolism

energy releasing (exergonic) decomposition reactions; digestion of foos, muscle breakdown, etc

catabolism

energy storing (endergonic) synthesis reactions: bone mineralization, muscle growth, tissue repair

anabolism

occur in cellular respiration and ATP production: oxidation (gives up electrons to release nrg) and reduction (molecule gains electrons and energy)

redox reactions

what are the four primary categories of organic molecules of life

carbs, lipids, proteins, and nucleic acid

small subunit which join together with other similar monomers through polymerization to create polymers

monomer

how is polymerization formed

dehydration by removing water

how is a polymer broken apart

hydrolysis by adding a water molecule

what monosaccharide and therefore carb is the energy for our cells

glucose

why do carbs matter physiologically

energy metabolism, glycogen storage, ex phys, cell recognition, and tissue structure

why are carbs important for energy metabolism

glucose is converted into ATP which is required for muscle contraction, active transport, and cellular metabolism

what do carbs also exist as on the outside of a cell membrane

glycoproteins and glycolipids

carb chain attached to protein and is used for cell-cell communicatiion, signaling, and immune response

glycoprotein

carb chain attached to a lipid and serves to maintain cell membrane stability, fluidity, and act as surface markers for cell recognition

glycolipid

hydrophobic, energy-dense, nonpolar organic molecule used for energy storage, insulation, and cell membranes

lipids

what are the primary types of lipids in humans

phospholipids, fatty acids, triglycerides, eicosanoids, and steroids

why are lipids fundamental for cell membrane structure

hydrophilic head and hydrophobic fatty acid tails that allow for cell permeability regulation, ion gradients, protection, membrane receptors, and supports nerve conduction

carbon compounds derived from a fatty acid (arachidonic acid) to function as a hormone-like chemical signal between cells for pain control and inflammation

eicosanoids

come from cholesterol adn include progesterone, estrogen, testosterone, and bile acids

steroids

what is the most important macromolecule and is a polymer of amino acids and teh specific combination determines its structure and function

proteins

what structure of a protein is an association of two or more seperate polypeptide chains (ex. hemoglobin)

quaternary structure

what are the functions of proteins

provide structure (collagen), allow communication (cell receptors), membrane transport (channels and carriers), catalysis (enzymes), recognition and protection (antigens, antibodies, clotting proteins), movement (molecular motor), and cell adhesion

type of protein that acts as biological catalysts and the specific shape determines the function

enzyme

what are the important aspects of enzymes

lowers activation energy, are reusable, and have astonishing speed

what are common enzyme inhibitors

ACE inhibitors that affect blood pressure and HMG-CoA reductase that are statins to lower cholesterol

factors that affect enzymes

inhibitors, temperature, and pH

how does temp affect enzymes and what is the optimal temp

changes the shape so alters its ability to bind: body temperature

nonprotein partners that bind to enzymes to change its shape

cofactors

organic cofactors derived from water-soluble vitamins that transfer electrons to and from enzymes

coenzymes

primary form is a genetic failure and secondary could be from statin use which causes pain and weakness

coenzyme Q10 deficiency

what are the three components of a nucleotide

nitrogenous base, sugar, phosphate group

what are some important nucleotides

ATP, cAMP (intracellular signaling messenger), DNA (genetic code), and RNA (assists with protein synthesis)