BIOL 117 WEEK 1 VOCABULARY + CONCEPTS

Content: 1.1-1.2, 1.9, 2.1-2.4, 3.8-3.13

physiology

the study of how living organisms function; ranges from the study of individual molecules to the complex processes that depend on the integrated funcitons of many organs in the body

pathophysiology

study of disease states (physiological dysfunction)

cells

the simplest structural units into which a complex multicellular organism can be divided and still retain the functions characteristic of life

cell differentiation

formation of four general types of specialized cells: muscle cells, neurons, epithelial cells, and connective-tissue cells

muscle cells

generate the mechanical activities that produce force and movement; 3 types: skeletal, cardiac, and smooth

neurons

initiate and conduct electrical signals

epithelial cells

form barriers/selectively secrete and absorb ions and organic molecules; basolateral surface rests on a basement membrane

connective-tissue cells

connect, anchor, and support the structures of the body; form the extracellular matrix (consists of fibers like collagen, elastin)

tissues

aggregates of differential cells with similar properties; correspond to the four general types of specialized cells (muscle, nervous, epithelial/epithelium, connective)

organs

composed of two or more of the four kinds of tissues (many contain multiple, small, similar functional units

organ system

group of organs that perform an overall function

skeletal muscle (cells + tissue)

attached through other structures to bones, produce movements of the limbs/trunk, also attached to skin; voluntary contraction

cardiac muscle (cells + tissue)

found only in the heart, generate force that causes the heart to contract/pump blood into ciruclation; involuntary muscle

smooth muscle (cells + tissue)

make up part of the walls of many of the tubes in the body, contraction decreases the diameter/shortens the length of these tubes; involuntary muscle

neurons

provide the major means of controlling the activities of other cells

nervous tissue

a collection of neurons (e.g. brain or spinal cord)

nerve

neuron extension which carries the signals from many neurons between the nervous system/other parts of the body

epithelial cells

characterized/named according to their unique shapes

cuboidal (cube-shaped)

columnar (elongated)

squamous (flattened)

ciliated

epithelia

located at surfaces that cover the body or individual organs; line inner surfaces of tubular and hollow structures

simple epithelium

single-cell-thick tissue

stratified epithelium

thicker tissue, numerous layers of cells

basement membrane

anchors the tissue, extracellular protein layer where epithelial cells rest on

basolateral side

the side anchored to the basement membrane

apical side

opposite side, faces the interior of a structure

tight junctions

cells are held together along their lateral surfaces by these extracellular barriers (selective) which regulate the exchange of molecules

loose connective tissue

connective tissue cells and fibers underlying most epithelial layers

dense connective tissue

tough, rigid tissue that makes up tendons/ligaments (other examples include bone, cartilage, and adipose)

extracellular matrix (ECM)

a mixture of proteins: polysaccharides (chains of sugar molecules) and sometimes minerals; provides sacffold for cellular attachments and transmits info in the form of chemical messengers to cells to regulate

what does the ECM regulate?

activity, migration, growth, and differentiation

fibers

some proteins of ECM; insoluble proteins including rope-like collagen fibers and rubberband-like elastin fibers; others are a mix of non fibrous proteins that contain carbohydrate

collagen

1/3 of all bodily proteins

organs (arragnement)

arranged in various proportions and patterns (sheets, tubes, layers, bundles, and strips); do not function in a vacuum they function together

functional units

small, similar subunits many organs are comprised of, perform function of the organ

circulatory system

major organs or tissues: heart, blood vessels, blood

primary functions: transport of blood throughout the body

digestive system

major organs or tissues: mouth, salivary glands, pharynx, esophagus, stomach, small and large intestines, anus, pancreas, liver, gallbladder

primary functions: digestion and absorption of nutrients and water; elimination of wastes

endocrine system

major organs or tissues: all glands/organs secreting hormones: pancreas, testes, ovaries, hypothalamus, kidneys, pituitary, thyroid, parathyroids, adrenals, stomach, small intestine, liver, adipose tissue, heart, and pineal gland; and endocrine cells in other organs

primary functions: regulation and coordination of many activities in the body, including growth, metabolism, reproduction, blood pressure, water and electrolyte balance, and others

immune system

major organs or tissues: white blood cells and their organs of production

primary functions: defense against pathogens

integumentary system

major organs or tissues: skin

primary functions: protection against injury and dehydration; defense against pathogens; regulation of body temperature

lymphatic system

major organs or tissues: lymph vessels, lymph nodes

primary functions: collection of extracellular fluid for return to blood; participation in immune defenses; absorption of fats from digestive system

musculoskeletal system

major organs or tissues: cartilage, bone, ligaments, tendons, joints, skeletal muscles

primary functions: support, protection, and movement of the body; production of blood cells

nervous system

major organs or tissues: brain, spinal cord, peripheral nerves and ganglia, sense organs

primary functions: regulation and coordination of many activities in the body, including most of those regulated by the endocrine system; detection of and response to changes in the internal and external environments; states of consciousness; learning; memory; emotion; others

reproductive system

major organs or tissues: males → testes, penis, and associated ducts and glands

females → ovaries, fallopian tubes, uterus, vagina, mammary glands

primary functions: males → production of sperm; transfer of sperm to female

female → production of eggs; provision of a nutritive environment for the developing embryo and fetus; nutrition of the infant

respiratory system

major organs or tissues: nose, pharynx, larynx, trachea, bronchi, lungs

primary functions: exchange of carbon dioxide and oxygen; regulation of hydrogen ion concentration in the body fluids

urinary system

major organs or tissues: kidneys, ureters, bladder, urethra

primary functions: regulation of plasma composition through controlled excretion of ions, water, and organic wastes

general principles of physiology

1. homeostasis is essential for health and survival

2. the functions of organ systems are coordinated with each other

3. most physiological functions are controlled by multiple regulatory systems, often working in opposition

4. information flow between cells, tissues, and organs is an essential feature of homeostasis/allows for integration of physiological processes

5. controlled exchange of materials occurs between compartments and across cellular membranes

6. physiological processes are dictated by the laws of chemistry and physics

7. physiological processes require the transfer and balamce of matter and energy

8. structure is a determinant of/has coevolved with function

atoms

units of matter that form all chemical substances

chemical element

each type of atom

components of atoms

protons

neutrons

electrons

atomic number

each chemical element contains a unique and specific number of protons; distinguishes one atom from another

atomic mass

indicates an atom’s mass relative to the mass of other atoms, unit is a dalton (d)

isotopes

have identical numbers of protons, differ in the number of neutrons they contain

radioisotopes

unstable isotopes, spontaneously emit energy/release components of the atom itself aka radiation

PET (positron emission tomography) scans

special imaging technique, used to detect how much of the radioactive glucose appears in different organs

gram atomic mass

amount of the element (in g) equal to the numerical value of its atomic mass

ion

certain atoms may gain/lose one or more electrons, acquire a net electrical charge

cations

net positive charge

anions

net negative charge

electrolytes

ionic forms of mineral elements

4 of the body’s essential elements

C - carbon

H - hydrogen

O - oxygen

N - nitrogen

molecules

formed by linking atoms together by chemical bonds

covalent bond

formed between two atoms that share a pair of electrons

polar covalent bond: one atom attracts the bonding e- more than the other atom of the pair

nonpolar covalent bond: formed between two atoms of similar electronegativities

ionic bond

strong bond between cations and anions; readily breaks in water

hydrogen bond

weak electrical attraction between H and O or N in different molecules/between different regions of one molecule (molecular shapes can be altered by the rotation of their atoms aorund covalent bonds

ionic molecules

molecules containing atoms that have ionized; common ionized groups include carboxyl groups (-COOH) / amino groups (-NH2)

electronegativity

measure of an atom’s ability to attact e- in a covalent bond

strong acids

hydrochloric acid and other acids that are completely ionized in solution

weak acids

do not completely ionize in solution

classes of organic molecules

carbohydrates, lipids, proteins, nucleic acids

carbohydrates

polar macromolecules consisting of monosaccharides (e.g. glucose), disaccharides (e.g. sucrose), and polysaccharides (e.g. glycogen, a polymer of glucose)

lipids

nonpolar molecules including triglycerides, phospholipids, fatty acids, and steroids

proteins

comprised of 20 different amino acids bound together by peptide bonds between the amino group of one amino acid and the carboxyl group of another

primary structure → amino acid sequence

secondary structure → beta-pleated sheets and alpha helices

tertiary structure → three-dimensional conformation (the final shape of a protein)

quaternary structure → multiple polypeptide chains bound together

nucleic acids

polymers of nucleotides (include DNA and RNA), responsible for the storage, expression, and transmission of genetic information

major categories and functions of proteins

ligand

any molecule (including a protein) that binds to proteins

binding states

regions in a protein with shapes typically complementary to the ligand; site of ligand bonding

chemical specificity

the likelihood of a particular protein binding only one ligand at its ligand-binding site

affinity

the strength of ligand-protein binding

saturation

fraction of total binding sites of a protein that are occupied by ligands

competition

occurs when more than one ligand is able to bind to the same binding site of a particular protein (typically with different affinities)

allosteric proteins

possess both a functional site and a regulatory site

protein kinase

enzymes that catalyze the addition of a phosphate group to side chains of certain amino acids in a protein (covalent modulation)

metabolism

synthesis (anabolism) and breakdown (catabolism) of organic molecules req. for cell function

activation energy

required to initiate the breaking of chemical bonds in a reaction; is usually acquired through collisions between molecules

catalysts

increase the rate of a reaction by lowering the activation energy

temperature

higher temp means increased reaction rate

reversible reaction

reaction that can proceed in either direction

enzymes

proteins that catalyze nearly all chemical reactions in the body; they act on substrates (reactants) to generate products and aren’t consumed by the reaction

cofactors

molecules or elements required in small concentrations by some enzymes for full activity

rates of enzyme-mediated reactions can be increased by

increase in: temperature, substrate conc. enzyme conc and enzyme activity

enzyme activity

altered by allosteric or covalent activation/inhibition; a given enzyme may have several regulatory sites

metabolic pathway

sequence of enzyme-mediated reactions leading to formation of a particular product

rate-limiting reaction

enzyme-catalyzed step that determines rate of product formation in a metabolic pathway

end-product inhibition

occurs when the end product of a metabolic pathway acts as a modulator molecule, inhibiting the rate-limiting enzyme’s ability