Anatomy & Physiology – Chapter 2 Flashcard

elements
substance composed of only one type of atom that cannot be broken into simpler constituents by chemical means
compounds
chemical combination of two or more elements
atoms
smallest particle of a chemical element that retains the properties of that element; particles that combine to form molecules
subatomic particles
particles that make up atoms; neutrons, protons, electrons
nucleus
dense, central core of an atom
protons
positively charged subatomic particle
neutrons
neutral subatomic particle
electrons
small, negatively charged subatomic particle
atomic number
number of protons in an atom of an element
mass number (atomic mass)
number of protons plus the number of neutrons in an atom of an element
energy level
limited region surrounding the nucleus of an atom at a certain distance containing electrons; shell
octet rule
atoms with fewer or more than eight electrons in the outer energy level will attempt to lose, gain, or share electrons with other atoms to achieve stability
inert
stable element; maximum amount of electrons in outer shell
atomic weight
average atomic mass of an atom of an element as it is found in nature; atomic weights are usually found in the periodic table of elements
radioisotope
unstable isotope that undergoes nuclear breakdown and emits nuclear particles and radiation
decay
emition of nuclear particles and radiation
chemical reaction
interaction between two or more atoms that occurs as a result of activity between electrons in their outermost energy levels
molecules
two or more atoms covalently joined together
chemical bonds
energy relationship joining two or more atoms; involves sharing or exchange of electrons
ions
electrically charged atom or group of atoms
ionic bond (electrovalent bond)
formed by transfer of electrons; strong electrostatic force that binds positively and negatively charged ions together
covalent bond
formed by sharing of electron pairs between atoms
single covalent bond
covalent bond with only one pair of shared electrons
double covalent bond
covalent bond with two pairs of shared electrons
hydrogen bond
weak chemical bond that occurs between the partial positive charge on a hydrogen atom covalently bound to a nitrogen or oxygen atom and the partial negative charge of another polar molecule
polar molecule
molecule in which the electrical charge is not evenly distributed, causing one side of the molecule to be more positive or negative than the other
synthesis reaction
combining of two or more substances to form a more complex substance
A + B -> AB
decomposition reaction
breaking down of a substance into two or more simpler substances
AB -> A + B
exchange reaction
decomposition of two substances and, in exchange, synthesis of two new compounds
AB + CD -> AD + BC
reversible reaction
occur in both directions
A + B <=> AB
metabolism
all of the chemical reactions that occur in body cells
catabolism
chemical reactions that break down complex compounds into simpler ones and release energy
anabolism
chemical reactionns that join simple molecules together to form more complex molecules
adenosine triphosphate (ATP)
broken down to supply energy for anabolism
hydrolysis
chemical process in which a compound is split by addition of H+ and OH- portions of a water molecule
dehydration synthesis
anabolic process by which molecules are joined to form larger molecules; often called condensation reaction because it joins molecules together into a denser mass
organic compound
contain covalently bound carbon and hydrogen atoms and are involved in metabolic reactions
inorganic compound
chemical constituents that do not contain both carbon and hydrogen
functional groups
small cluster of atoms in an organic molecule that gives the molecule particular functional characteristics such as certain chemical binding properties; often represented generically by the letter R
property of water
strong polarity
polar water molecules attract other polar compounds, which causes them to dissociate/separate
property of water
high specific heat
hydrogen bonds absorb heat when they break and release heat when they form, thereby minimizing temperature changes
property of water
high heat of vaporation
many hydrogen bonds must be broken for water to evaporate
property of water
cohesion
hydrogen bonds hold molecules of water together
oxygen (O2)
required to complete the decomposition reactions required for the release of energy from nutrients burned by the cell
carbon dioxide (CO2)
involved in cellular respiration; produced as a waste product during the breakdown of complex nutrients and also serves an important role in maintaining the appropriate acid-base balance in the body
electrolytes
substance that dissociates into ions in solution, rendering the solution capable of conducting an electric current
acid
any substance that releases a hydrogen ion (H+) when in solution (proton donor)
strong acid
acid that completely or almost completely dissociates to form H+ ions
weak acid
acid that dissociates very little and therefore produces few excess H+ ions in solution
base (alkaline)
electrolytes that dissociate to yield hydroxide ions (OH-) or other electrolytes that combine with hydrogen ions
pH
indicates degree of acidity or alkalinity (base) of a solution
pH = 7 = neutrality
pH > 7 = alkalinity (base)
pH < 7 = acidic
buffers
minimize changes in concentrations of H+ and OH- ;maintain constancy of pH
salt
compound that results from chemical interaction of an acid and a base
neutralization reaction
reaction between an acid and a base to form a salt and water
carbohydrate
organic compounds containing carbon, hydrogen, and oxygen; commonly called sugars and starches
monosaccharides
simple sugars with short carbon chains (glucose)
hexose
monosaccharides with six carbons
pentoses
monosaccharides with five carbons
disaccharides
two simple sugars (monosaccharides) that are bonded together through a dehydration synthesis reaction
polysaccharides
more than two simple sugars that are bonded together through a dehydration synthesis reaction
polymer
large molecule made up of many identical smaller molecules joined together in sequence
glycogen
polysaccharide; main carbohydrate stored in animal cells
lipids
water-insoluble organic molecules that are critically important biological compounds
nonpolar
describes a covalent chemical bond in which there is equal sharing of electrons and therefore no distinct areas of electrical charge
triglycerides
lipid that is synthesized from fatty acids and glycerol or from excess glucose or amino acids; stored mainly in adipose tissue cells
fatty acids
product of fat digestion; building block of fat molecules
saturated fatty acid
fatty acid in which all available bonds of its hydrocarbon chain are filled, that is, saturated, with hydrogen atoms
unsaturated fatty acid
fatty acid that has one or more double bonds in its hydrocarbon chain because not all the chain’s carbon atoms are saturated with hydrogen atoms
phospholipids
phosphate-containing fat molecule; an important constituent of cell membranes
hydrophilic
water loving
hydrophobic
water fearing
steriods
any of a class of lipids related to sterols and forming numerous reproductive and adrenal hormones
prostaglandins (tissue hormones)
any of a group of naturally occurring lipid-based substance that act in a hormone-like way to affect many body functions, including vasodilation, uterine smooth muscle contraction, and the inflammatory response
proteins
large molecules formed by linkage of amino acids by peptide bonds; one of the basic building blocks of the body
enzymes
biochemical catalyst that allows chemical reactions to take place; functional proteins that regulate various metabolic pathways of the body
amino acids
type of chemical unit from which proteins are built; also have other functions made up of a carbon atom to which are bonded an amino group and carboxyl group
peptide bond
bond that forms between the amino group of one amino acid and the carboxyl group of another
primary structure of protein
protein structure is a sequence of amino acids in a chain
secondary structure of protein
protein structure is formed by folding and twisting of amino acid chain
tertiary structure of protein
protein structure is formed when the twists and folds of the secondary structure fold again to from a larger 3D structure
quaternary structure of protein
protein structure is a protein consisting of more than one folded amino acid chain
chaperones
any of a group of globular proteins that are present in every body cell and direct the intracellular steps required for other proteins to achieve the often twisted and convoluted shape required for them to function
structural proteins
any of a category of proteins with the primary function of forming structures of the cell or tissue; contrast with functional protein
functional proteins
category of proteins that affect the functional operations of a cell; contrast to structural protein
denatures
to alter the shape of a protein by a change in pH, heat, or some other manner to change its chemical properties
nucleic acid
any of the high-molecular-weight organic compounds composed of nucleotides, a ribose or deoxyribose sugar, and a phosphate group
nucleotides
monomer made up of three types of chemical groups (sugar, phosphate, nitrogen base) that can act alone or to make up a polymer
deoxyribonucleic acid (DNA)
genetic material of the cell that carries the chemical “blueprint” of the body
ribonucleic acid (RNA)
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
high-energy bonds
chemical bond that requires and input of energy to form and when broken can result in the transfer of useful energy to cellular processes, as in ATP
chemistry
science of the structure and interactions of matter
matter
anything that occupies space and has mass; 3 Phases of Matter – Solid, Liquid, Gas
mass
the amount of matter a substance has, both living and nonliving things consist of matter and mass

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