Anatomy and Physiology Midterm 1

anatomy

describes the structures of the body and how the parts fit together

physiology

describes the function of the body parts and how they work

structure

structure of a body part affects its function

function

function of a body part affects its structure mechanically or chemically → informs and shape the structure

Levels of Organization - smallest to largest

Chemical level → cellular level → tissue level → organ level → system level → organismal level

Homeostasis

condition of equilibrium through regulation and feedback adjusting to get to healthy system normal - most homeostatic controls are negative feedback

2 systems that regulate homeostasis

Nervous system → sends nerve impulses - fast and specific

Endocrine system → sends hormones - slower and broader

Receptor

detects changes and sends signal to control centre

control centre

determines set point and creates a response to an effector

effector

carries out appropriate response to get back to equilibrium to either reduce or amplify stimulus

negative feedback

the response reduces/stops the stimulus preventing severe change within the body → back to normal healthy (set point)

response

decreases the difference between the current level and set point

positive feedback

the response enhances or magnifies the stimulus, and amplifies its effect - controls events that do not require continuous adjustment

homeostatic imbalance

occurs when the control centre cant respond properly to stimulus. leads to dysfunction and disease

anatomical position

human standing, feet apart, palms forward, thumbs away from body

axial division

head and torso

appendicular division

limbs - arms and legs

sagittal section

divides body into left and right

frontal section

divides the body into front and back

transverse section

divides the body into top and bottom

dorsal body cavity

contains cranial cavity and vertebral cavity

ventral body cavity

contains thoracic cavity and abdominopelvic cavity

parietal serosa

lines body cavities

visceral serosa

lines organs

matter

mass and occupies space

energy

puts matter into motion

potential energy

stored energy

elements of human body - macromolecules

oxygen 65%, carbon 18%, hydrogen 10%, nitrogen, 3% - make up 96% human body mass

lesser elements comprise

2.6% body mass

trace elements comprise 

<0.4%

Calcium

adds hardness to bones and teeth - essential for nerve and muscle function

Magnesium

helps muscle and nerve functions and bone health. maintains blood glucose levels and helps absorbs nutrientsp

Phosphorus

essential for DNA and RNA and for making ATP

Sodium and Potassium

produced electrical activity in neurons and muscle cells

sulfur

used to make amino acids for building proteins

iron

used to carry oxygen in our RBC

zinc

helps replicate DNA, produce more immune cells

Iodine

regulates metabolism

elements are defined by

atomic number and atomic massi

isotopes

atoms that have a diff number of neutrons than normal for that element

anion

gains electrons and is negative charge

cation

loses electrons and is positive charge

molecules

2 or more atoms together

molecule

two or more different elements

mixture

made of different types of molecules

synthesis reaction

2 components combined to make a larger more complex molecule - anabolic building activity

decomposition reaction

bonds are broken between components of a larger molecule - catabolic bondbreaking activity

exchange reaction

bonds are broken and formed to rearrange the components of the reactants - involves both synthesis and decomposition

reduction-oxidation reaction

reduced when gain electrons

oxidized when lose electrons

LEO GER

glucose oxidized oxygen reduced

increases rate of chem rxns

temperature, concentration of reactants, particle size

catalysts

increase rate of rxn without being chemically changed or becoming part of product. - ie enzyme

biochemistry

the study of chemical composition and rxns of living matter

inorganic compounds

does not contain carbon

organic compounds

large compounds that contain carbon

water

most abundant inorganic compound 60-80% volume of living cellswa

water properties

high heat capacity - stabilize temp

high heat of vaporization - helps w cooling

reactivity - hydrolysis and dehydration synth.

cushion and lubrication

water dissolves

ionic and polar substances

dehydration synthesis

covalent bond is created by removing OH from one molecule and H from another releasing H2O

hydrolysis

covalent bond is broken by adding OH from water to one molecule and H to the other 

ions are also

electrolytes because it conducts electrical currents in a solution

acids

proton donors - releases hydrogen ions H+

bases

proton acceptors - absorbs H+ in solution releases OH-

neutralization reaction

occurs when acids and bases are mixed together - displacement rxn occurs and forms water and a salt

buffers

resists large changes can act like a weak acid or weak base

bicarbonate buffer

maintains blood pH

monosaccharides

single sugar units made of 3-7 carbons

disaccharides

formed by dehydration synthesis of 2 monosaccharides 

polysaccharides

large chains of monosaccharides joined together by dehydration synthesis

starch

used for glucose storage in plant cells

glycogen

used for glucose storage in animal cells - in liver to help blood sugar levels

cellululose

made of glucose but most animals do not have enzymes to hydrolyze it 

triglycerides

stores energy, insulates, and protects

phospholipids

used in cell membranes - made up of a glycerol and 2 fatty acids plus a phosphate group

steroids

signalling molecules like hormones

saturated fatty acids

all carbons linked via single covalent bonds - solid at room temp.

unsaturated fatty acids

one or more carbons are linked by double bonds so it’s not saturated with hydrogen atoms. liquids at room temp

prostaglandins (an eicosanoid)

regulates blood pressure and inflammation increases pain receptors and induces fever

nonsteroidal anti-inflammatory drug NSAID

inhibits prostagladins to decrease pain, inflammation, and fever. ie asprin and ibuprofen

proteins

amino acids held together with covalent bonds

peptide bond

amine group and acidic carboxyl group

all human proteins

20 diff types of amino acids → one amine group and carboxyl groups plus 20 diff R side chains

r group side chains

give each amino acid its characteristics → size, polarity, and pH

primary structure

order of amino acids in the polypeptide chain → hard to break peptide bonds need an enzyme to break it

secondary structure

refers to shapes like alpha helices and beta pleated sheets that form w/ amino acids from the primary structure interact w/ each other through hydrogen bonds

tertiary structure

the three-dimensional shape of a single polypeptide chain. shape comes from how chain folds, based on regions of amino acids that are hydrophilic or hydrophobic or disulphide bridges

quarternary structure

occurs when 2 or more polypeptide chains join tgt to make one functional protein multimer - not all proteins have quartnerary structure

fibrous proteins

rope-like insoluable molecules that are hard to break

globular proteins

compact spherical, water soluable, chemically active molecules that oversee cellular functions. ie. enzyme, protein, antibodies, hormones

protein denaturation

loss of the specific 3-D structure of a globular protein leading to loss of function. done by either change in pH or temperature

enzymes

lower activation energy for a chemical reaction and increases rate of rxn without needed high temperatures

enzyme consist of

apoenzyme (protein portion) and cofactors (metal ions) or coenzymes(organic molecules)

holoenzymes

apoenzymes together with necessary cofactors or coenzymes

enzyme substrate complex

enzyme and substrate together at an active site - catalyzes rxn and turns substrate into products

DNA nucleotides

has a deoxyribose sugar nitrogen base and a phosphate group

purines

adenine and guanine

pyrimidines

cytosine and thymine

purine pairs with pyrimidine by

hydrogen bonding

base pairing

A-T and G-C

DNA and RNA strands are

synthesized from 5’ to 3’

RNA is used

to take nucleotide sequence info from DNA and use to make proteins