Anatomy & Physiology I Vocabulary Ch 2

Front 1

elements

Back 1

substance composed of only one type of atom that cannot be broken down further

Front 2

compounds

Back 2

a chemical combination of two or more elements

Front 3

atoms

Back 3

smallest particle of a chemical element that retains the properties of that element

Front 4

energy level/shell

Back 4

region surrounding the nucleus of an atom that contains electrons

Front 5

octet rule

Back 5

principle that atoms form bonds in ways that will provide each atom with an outer shell of eight electrons

Front 6

isotopes

Back 6

element that has the same number of protons, but different numbers of neutrons

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molecule

Back 7

formed when two or more atoms join

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ions

Back 8

electrically charged atom or groups of atoms

Front 9

ionic bond

Back 9

bond formed by transferring of electrons from one atom to another

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polar

Back 10

molecule in which the electrical charge is not evenly distributed, causing one side to be more positive or negative than the other

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synthesis

Back 11

combination; the combination of molecules to form a larger molecule

Front 12

decomposition reactions

Back 12

chemical reaction that breaks down a substance into two or more simpler substances

Front 13

exchange reactions

Back 13

chemical reaction that breaks down a compound and then synthesizes a new compound by switching portions of the molecules

Front 14

reversible reactions

Back 14

when the products of a chemical reaction change back to the original reactants; generally, an equilibrium of products and reactants exists

Front 15

metabolism

Back 15

complex, intertwining set of chemical processes by which life is made possible for a living organism

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catabolism

Back 16

breakdown of food compounds or cytoplasm constituents into simpler compounds

Front 17

anabolism

Back 17

cells making complex molecules from simpler compounds

Front 18

adenosine triphosphate (ATP)

Back 18

chemical compound that provides energy for use by body cells

Front 19

functional groups

Back 19

small cluster of atoms in an organic molecule that gives the molecule particular functional characteristics

Front 20

electrolytes

Back 20

substance that dissociates into ions in solution, making it capable of conducting an electric current

Front 21

acid

Back 21

substance that ionizes in water to release hydrogen ions; substances with a pH less than 7.0

Front 22

bases/alkaline compounds

Back 22

substance that ionizes in water to decrease the number of hydrogen ions

Front 23

pH

Back 23

units by which acid and base concentrations are measured; scale from 0-14, where 7 is neutral, 0-6 is an acid and 8-14 is a base

Front 24

buffers

Back 24

compound that combines with an acid or with a base to form a weaker acid or base, thereby lessening the the change in hydrogen ion concentration that would occur without the buffer

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carbohydrates

Back 25

organic compounds containing carbon, hydrogen, and oxygen in certain specific proportions

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types of carbohydrates

Back 26

1. monosaccharides (simple sugars)
2. disaccharides (double sugars)
3. polysaccharides (complex sugars)

Front 27

lipids

Back 27

class of organic compounds that includes fats, oils, and related substances

Front 28

nonpolar

Back 28

without charged regions

Front 29

triglycerides

Back 29

lipid that is synthesized from fatty acids and glycerol or from excess glucose or amino acids; stored mainly in adipose tissue cells

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phospholipids

Back 30

phosphate-containing fat molecule; an important constituent of cell membranes

Front 31

steroids

Back 31

any of a class of lipids related to sterols and forming numerous reproductive and adrenal hormones

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prostaglandins

Back 32

any of a group of naturally occurring lipid-based substances that act in a hormone-like way to affect many body functions, including vasodilation, uterine smooth muscle contraction, and the inflammatory response

Front 33

proteins

Back 33

large molecules formed by linkage of amino acids by peptide bonds; one of the basic building blocks of the body

Front 34

enzymes

Back 34

biochemical catalyst that allows chemical reactions to take place; functional proteins that regulate various metabolic pathways of the body

Front 35

amino acids

Back 35

type of chemical unit from which proteins are built

Front 36

peptide bond

Back 36

bond that forms between the amino group of one amino acid and the carboxyl group of another

Front 37

dehydration synthesis

Back 37

anabolic process by which molecules are joined to form larger molecules

Front 38

hydrolysis

Back 38

chemical process in which a compound is split by addition of H+ and OH- portions of a water molecule

Front 39

levels of protein structure

Back 39

1. primary (first level)
2. secondary (second level)
3. tertiary ( third level)
4. quaternary (fourth level)

Front 40

structural proteins

Back 40

any of a category of proteins with the primary function of forming structures of the cell or tissue

Front 41

functional proteins

Back 41

category of proteins that affect the functional operations of a cell

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denatures

Back 42

to alter the shape of a protein by a change in pH, heat or some other manner to change its chemical properties

Front 43

nucleotides

Back 43

monomer made up of three types of chemical groups that can act alone or to make up a polymer

Front 44

high-energy bonds

Back 44

chemical bond that requires an input of energy to form and when broken can result in the transfer of useful energy to cellular processes, as in ATP

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transfer RNA (tRNA)

Back 45

RNA involved with protein synthesis; tRNA molecules carry amino acids to the ribosome for placement in the sequence prescribed by mRNA

Front 46

messenger RNA (mRNA)

Back 46

duplicate copy of a gene sequence on the DNA that passes from the nucleus to the cytoplasm; used by ribosomes to create specific proteins

Front 47

RNA interference (RNAi)

Back 47

nucleic acid found in both nucleus and cytoplasm of cells; involved in transmission of genetic information from nucleus to cytoplasm and in cytoplasmic assembly of proteins

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hypercapnia

Back 48

excessive carbon dioxide in the blood

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acidosis

Back 49

condition in which there is an excessive proportion of acid in the blood and thus an abnormally low blood pH; opposite of alkalosis

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toxins

Back 50

poison; chemical that can cause sickness or damage in the body