A&P exam 1

organization

levels of biological organization extends within (micro) and beyond (macro) the individual as follows:

atoms --> molecules --> organelles --> cells --> tissues --> organs --> organ systems --> organisms --> populations --> communities --> ecosystems --> biosphere

matter

has mass and occupies space, three forms are solid (bone), liquid (blood), and gas (oxygen)

atom

smallest particle exhibiting chemical properties of an element, 92 naturally occurring elements make up matter, organized in periodic table of elements

components of atom

composed of three subatomic particles: neutrons, protons, electrons

neutrons

mass of one atomic mass unit (amu), no charge

protons

mass of one amu, positive charge of one (+1)

electrons

negative charge of one (-1), located at varying distance from nucleus in regions called orbitals

chemical symbol of periodic table

unique to each element, usually identified by first letter or first letter plus an additional letter

atomic number of periodic table

number of protons in atom of element, located above symbol name, elements arranged by anatomic number within rows

average atomic mass of periodic table

mass of both protons and neutrons, shown below element's symbol on table

determining the number of subatomic particles

proton number = atomic number

neutron number = atomic mass - atomic number ((p + n) - p)

electron number = proton number

diagramming atomic structures

atom has shells of electrons surrounding nucleus, each shell has given energy level, each shell holds limited number of electrons, innermost shell: two electrons, second shell up to eight, shells close to nucleus must be filled first

isotope

different atoms of same element, same number of protons and electrons, different number of neutrons, identical chemical characteristics, different atomic masses

i.e. carbon-12 with 6 neutrons, carbon-13 with 7 neutrons, carbon-14 with 8 neutrons

average atomic mass

weighted average of atomic mass for all isotopes

radioisotopes

contain excess neutrons, so unstable, lose nuclear components in form of high energy radiation

i.e. alpha particles, beta particles, gamma ray

physical half-life

time for 50% of radioisotope to become stable, can vary from a few hours to thousands of years

biological half-life

time required for half of radioactive material from test to be eliminated from body

chemical compounds

stable associations between two or more elements combined in fixed ratio, classified as ionic or molecular

ionic compounds

structures composed of ions held together in lattice by ionic bonds

ions

atoms with positive or negative charge, produced from loss or gain of one or more electrons, significant physiological functions (K+ is used in sports drinks to replace K+ lost in sweat, K+ in large dose is used in some states for lethal injection)

cations

ions with positive charge

sodium can reach stability by donating electron, now satisfies octet rule, now has 11 protons and 10 electrons, charge is +1

anions

ions with negative charge

chlorine reaches stability by gaining electron, now satisfies octet rule, now has 17 protons and 18 electrons, charge is -1

polyatomic ions

anions with more than one atom

i.e. bicarbonate ion and phosphate ion

ionic bonds

cations and anions bound by electrostatic forces, form salts

i.e. table salt (NaCl), each sodium atom loses one outer shell electron to chlorine atom, sodium and chlorine ions are held together by ionic bonds in lattice crystal structure (ionic compound)

i.e. magnesium chloride, each magnesium atom loses one electron to each of the two chlorine atoms

covalently bonded molecule

electrons shared between atoms of two or more different elements, termed molecular compounds

i.e. carbon dioxide (CO2), but not molecular oxygen (O2) (bc only one atom)

occurs when both atoms require electrons, occurs with atoms with 4 to 7 electrons in outer shell, formed commonly in human body using

i.e. H, O, N, C

simplest occurs between two hydrogen atoms - each sharing its single electron, oxygen needs two electrons to complete outer shell - forms two covalent bonds, nitrogen forms three bonds, carbon forms four bonds

molecular formula

indicates number and type of atoms

i.e. carbonic acid (H2CO3)

structural formula

indicated number and type of atoms, indicated arrangement of atoms within molecule, allows differentation of isomers, same number and type of elements but arranged differently in space

i..e O = C = O (carbon dioxide)

glucose vs galactose vs fructose

same molecular formula, 6 carbon 12 hydrogen 6 oxygen, atoms arranged differently, isomers may have different chemical properties

single covalent bond

one pair of electrons shared, i.e. between two hydrogen atoms

double covalent bond

two pairs of electrons shared, i.e. between two oxygen atoms

triple covalent bond

three pairs of electrons shared, i.e. between two nitrogen atoms

carbon skeleton formation

bonds in straight chains, branched chains, or rings, carbon present where lines meet at angle, additional atoms are hydrogens

electronegativity

relative attraction of each atom for electrons, determines how electrons are shared in covalent bonds, in periodic table electronegativity increases from left to right across row and from bottom to top in column

i.e. hydrogen < carbon < nitrogen < oxygen

more electronegative atom develops partial negative charge (δ−), less electronegative atoms develops partial positive charge (δ+), exception to rule of polar bond forming between two different atoms (carbon bonding with hydrogen)

nonpolar covalent bond

two atoms of same element have equal attraction for electrons, nonpolar molecules contain nonpolar covalent bonds, nonpolar molecules may contain polar covalent bonds if polar covalent bonds cancel each other (i.e. carbon dioxide)

i.e. O - O and C - H are nonpolar bonds

polar covalent bond

sharing of electrons unequally, polar molecules contain polar covalent bonds

i.e. O - H is polar bond in polar molecule water (H2O)

amphipathic molecules

large molecules with both polar and nonpolar regions, i.e. phospholipids

intermolecular attractions

weak chemical attractions between molecules, important for shape of complex molecules

i.e. DNA and proteins

hydrogen bond

forms between polar molecules, attraction between partially positive hydrogen atom and partially negative atom, individually weak, collectively strong, influences how water molecules behave

van der waals forces

nonpolar molecules, electrons orbiting nucleus briefly unevenly distributed, induce unequal distribution of adjacent atom of another nonpolar molecule, individually weak

hydrophobic interaction

excluded molecules, nonpolar molecules placed in polar substance, if occurring between parts of large molecules then termed intramolecular attractions

molecular structure of water

composes 2/3 of human body by weight, polar molecule, one oxygen atom bonded to two hydrogen atoms, oxygen atom has two partial negative charges, hydrogens have single partial positive charge, can form four hydrogen bonds with adjacent molecules, central to water's properties

three phases of water (depending on temperature)

(1) gas (water vapor), substances with low molecular mass (2) liquid (water), almost all water in the body, liquid at room temperature due to hydrogen bonding (3) solid (ice)

functions of liquid water

transports: substances dissolved in water move easily throughout body, lubricates: decreases friction between body structures, cushion: absorbs sudden force of body movements, excretes wastes: unwanted substances dissolve in water are easily eliminated

properties of water

cohesion, surface tension, adhesion, temperature, specific heat, heat of vaporization,

cohesion

attraction between water molecules due to hydrogen bonding

surface tension

inward pulling of cohesive forces at surface of water, causes moist sacs of air in lungs to collapse, surfactant, a lipoprotein, prevents collapse

adhesion

attraction between water molecules and substance other than water

temperature

measure of kinetic energy of atoms or molecules within substance

i.e. vasoconstriction and vasodilation

specific heat

amount of energy required to increase temperature of 1 gram of substance by 1 degree Celsius, water's value extremely high due to energy needed to break hydrogen bonds, contributes to keeping body temperature constant

heat of vaporization

heat required for release of molecules from a liquid phase into a gaseous phase for 1 gram of a substance, water's value very high due to hydrogen bonding, sweating cools body, excess heat dissipated as water evaporates

substances that dissolve in water

polar molecules and ions (hydrophilic), water surrounds substances and forms hydration shell, (1) some substances dissolve but remain intact (glucose and alcohol), nonelectrolytes remain intact but do not conduct current, (2) substance dissolve and dissociate (separate), NaCl dissolves into Na+ and Cl- ions, acids and bases (HCl), electrolytes can conduct current

substances that do not dissolve in water

nonpolar molecules (hydrophobic), hydrophobic substances require carrier proteins to be transported within blood

i.e. fats and cholesterol are unable to dissolve within water

hydrophobic exclusion

cohesive water molecules "force out" nonpolar molecules

substances that partially dissolve in water

amphipathic molecules have polar and nonpolar regions, polar portion of molecule dissolves in water, nonpolar portion repelled by water, phospholipid molecules are amphipathic, polar heads have contact with water, nonpolar tails group together, results in bilayers of phospholipid molecules (membranes of cell), other amphipathic molecules form a micelle

water: a neutral solvent

water spontaneously dissociates to form ions, bond between oxygen and hydrogen breaks apart spontaneously, OH group hydroxide ion (OH-), hydrogen ion transferred to second water molecule (hydronium ion: H3O+), equal numbers of positive hydrogen ions and negative hydroxyl ions produced, water remains neutral

H2O + H2O --> H3O+ + OH- (or simplified: H2O --> H+ + OH-)

acids

dissociate in water to produce H+ and anion, proton donor, increases concentration of free H+, more dissociation of H+ with stronger acids (HCl in stomach), less dissociation of H+ with weaker acids (carbonic acid in blood)

substance A (acid in water) --> H+ + anion

bases

accepts H+ when added to solution, proton acceptor, decreases concentration of free H+, more absorption of H+ with stronger bases (ammonia and bleach), less absorption of H+ with weaker bases (bicarbonate in blood and in secretions released into small intestine)

substance B (base in water) + H+ --> B - H

neutralization

when acidic or basic solution is returned to neutral (pH 7), acids neutralized by adding base (medications to neutralize stomach acid must contain base), bases neutralized by adding acid

buffers

help prevent pH changes if excess acid or base is added, act to accept H+ from excess acid or donate H+ to neutralize base

i.e. carbonic acid (weak acid) and bicarbonate (weak base) buffer blood pH, both help maintain blood pH in critical range (7.35 to 7.45)

mixtures

formed from combining two or more substances, two defining features: substances mixed are not chemically changed, substances can be separated by physical means (evaporation or filtering)

three categories of water mixtures

suspension, colloid, solution

suspension

material larger in size than 1 mm mixed with water, does not remain mixed unless in motion, appears cloudy or opaque, scatters light

i.e. blood cells within plasma or sand in water

emulsion

special category of suspension, water and nonpolar liquid substance, does not mix unless shaken

i.e. oil and vinegar salad dressing or breast milk

colloid

smaller particles than suspension but larger than those in solution, remains mixed when not in motion, scatter light

i.e. fluid in cell cytosol and fluid in blood plasma

solution

homogeneous mixture of material smaller than 1 nm, dissolves in water, does not scatter light, does not settle if solution not in motion

i.e. sugar water, salt water, blood plasma

mass/volume

mass of solute per volume of solution

i.e. results from blood test

mass/volume percent

grams of solute per 100 mL solution

i.e. IV solutions

molarity

moles solute/L solution, alters with changes in temperature, more easily measure in body than molality

molality

moles solute/kg solvent, does not alter with changes in temperature, slightly more accurate than molarity

mole

6.022 x 10^23 atoms, ions, or molecules, mass in grams equal to atomic mass of element or molecular mass of compound

ATP

adenosine triphosphate, nucleotide composed of nitrogenous base adenine, ribose sugar, and three phosphate groups, central molecule in transfer of chemical energy within cell, covalent bonds between last two phosphate groups are unique and energy rich, release energy when broken

important nucleotide-containing molecules

nicotinamide adenine dinucleotide, flavin adenine dinucleotide, both participate in production of ATP

anatomy

studies form and structure of body

physiology

examines how body functions, examine function of body structures, focusing on molecular and cellular level

homeostasis

maintenance of relatively stable internal conditions despite continuous changes in environment, dynamic state of equilibrium, always readjusting as needed, maintained by contributions of all organ systems

hippocrates and aristole

founder of anatomy - herophilus of chalcedon

hippocrates

greek physician, father of western medicine, first to separate disease from superstition, key players in early anatomy

herophilus and eristratus

vivisections of criminals

middle ages, renaissance, 17 and 18th centuries

middle ages: study of anatomy outlawed

renaissance: anatomical interest/knowledge reestablished

17 and 18th centuries: anatomists like celebrities, people paid to see dissections in large amphitheaters

gross or macroscopic anatomy

study of large visible structures, regional anatomy, systemic anatomy (cardiovascular, nervous, muscular), surface anatomy, deep anatomy, comparative anatomy

microscopic anatomy

cytology: microscopic study of cells

histology: microscopic study of tissues

physiology subdisciplines

cardiovascular physiology, neurophysiology, respiratory physiology, reproductive physiology, pathophysiology

cardiovascular physiology

examines functioning of heart, blood vessels, and blood

neurophysiology

studies functioning of nerves and nervous system organs

respiratory physiology

explores functioning of respiratory organs

reproductive physiology

investigates functioning of reproductive hormones and reproductive cycle

pathophysiology

focuses on function of body system during disease or injury to system

anatomic position

upright stance, feet parallel and flat on floor, upper limbs at sides of body, palms face anteriorly (toward front), head is level, eyes look forward

section

slice that exposes internal anatomy

plane

imaginary flat surface passing through body

coronal (or frontal) plane, transverse (or cross-sectional) plane, midsagittal (or median) plane, sagittal plane, oblique plane

anterior/posterior

anterior: in front of, aka ventral, i.e. sternum is anterior to spine

posterior: back of body, behind, aka dorsal, i.e. heart is posterior to ribcage

superior/inferior

medial/lateral

medial: toward middle of body, inner side of, i.e. nose is medial to eye

lateral: away from midline, on other side of, i.e. ear is lateral to eye

proximal/distal

proximal: closer to point of attachment of limb to body trunk, i.e. elbow is proximal to wrist

distal: further from point of attachment of limb to body trunk, i.e. knee is distal to thigh

superficial/deep

superficial: toward body's surface, aka eternal, i.e. skeletal muscles are superficial to bones

deep: away from body's surface, internal, i.e. lungs are deep to ribs

integumentary system

protects body, receives sensory input, helps control temperature, synthesizes vitamin D

cardiovascular system

transports blood, nutrients, gases, and wastes, defends against disease, helps control temperature, fluid, and pH balance

lymphatic and immune systems

help control fluid balance, absorb fats, defend against infectious disease

digestive system

ingests food, digests food, absorbs nutrients, eliminates waste

respiratory system

maintains breathing, exchanges gases at lungs and tissues, helps control pH balance