Chapter 2 Flashcards
chemistry
study of matter, what its made of, how its put together, and how it interacts with energy
molecule
smallest unit of a compound. The smallest substance that retains the chemical
compound
contains atoms of different elements chemically combined in a fixed ratio.
3 forms of matter
liquid (holds volume(, solid (holds shape and volume), gas (holds neither)
atom
smallest particle that exhibits the chemical properties of an element
protons
positive charge of one
neutrons
no charge
electrons
negative charge of one; in orbitals
chemical compound
stable associations between 2 or more elements combined in a fixed ratio (ionic or molecular)
molecular compound
consists of molecules rather than ions, each atom shares enough electrons to fill valence shell (covalent).
ion
atom with a charge, produced from loss or gain of an electron
cations
positively charged ions
anions
negatively charged ions
Na+
most common extracellular cation, electrical signals in neurons
Ca2+
for blood clotting and muscle contraction
Cl-
in stomach acid
ionic bonds
cations and anions may bind to form an ionic bond. This bond donates or accepts electrons and is very strong
assigning charge rules
atoms with 1-3 electrons in valence will become cations, 5-7 = anions
covalent bond
atoms share electrons, occurs when both atoms require electrons (4-7 in valence)
four elements in the human body that form covalent bonds most commonly
carbon, hydrogen, oxygen, nitrogen (CHON)
acid
a substance that dissociates in water to produce H+ and an anion; also called a proton donor (these solutions have a greater H+ than OH-)
base
accepts H+ when added to a solution; also called proton acceptor (these solutions have greater OH- than H+
pH
measure of how much H+ is in a solution. expressed as a number 0-14. a move from one # to the next is a tenfold change.
neutral pH
solution with equal concentration of H+ and OH-
neutralization
occurs when an acidic or basic solution is returned to neutral (neutralized by adding opposites)
buffers
prevent pH changes if excess acid or base is added by accepting H+ from acids and donating H+ to neutralize bases
organic molecules
molecules that contain carbon and hydrogen. biomolecules are a subset
classes of biomolecules
lipids, carbs, nucleic acids, proteins
Lipids
function as stored nutrients, cellular membrane components, and hormones. Monomers are fatty acids and glycerol.
4 main types of fatty acids
triglycerides, phospholipids, steroids, eicosanoids
triglycerides
Formed from a glycerol molecule and three fatty acids. most common lipid in living things, functions to store energy, structural support, cushioning, and insulation.
adipose tissue
forms triglycerides when energy is excess (lipogenesis) and breaks down triglycerides when needed (lipolysis)
phospholipids
structure has one end of the glycerol with a phosphate group with another organic group which makes the hydrophilic head and a fatty acid group that is the hydrophobic tails. amphipathic (hydrophobic and hydrophilic) molecules forming cell membranes and repair cells.
steroids
Helps control metabolism, inflammation, sex characteristics, immune function and more. ringed hydrocarbons. include cholesterol, steroid hormones, and bile salts.
Eicosanoids
20 carbon fatty acids. made from arachidonic acid and function as local signaling molecules and inflammatory responses
classes of eicosanoids
prostaglandins, prostacyclins, thromboxanes, leukotrienes
glycolipids
lipid molecules with carbs attached, involved in cellular binding in plasma membrane
carbs
an H- and OH- usually attached to every carbon. chemical formula= (CH2O)2. Monomers are monosaccharides, short term energy
glucose and glycogen
glucose is a 6 carbon carb, most common monosaccharide, mainly supply energy to cells. Glycogen is its polysaccharide
glycogenesis and glycogenolysis
construction or destruction of glycogen
monosaccharides
glucose, galactose, fructose, ribose, deoxyribose
disaccharides
sucrose, lactose, maltose
polysaccharides
glycogen in animals, starch and cellulose in plants
nucleic acids
store and transfer genetic information. monomer is nucleotides. nucleotides are made up of a sugar molecule, phosphate, and nitrogenous base
Dna
double stranded nucleic acid found in chromosomes in nucleus and mitochondria
rna
single stranded nucleic acid in nucleus and within cytoplasm of a cell
purines
adenine, guanine
pyrimidines
cytosine, uracil
atp
adenine, ribose, and 3 phosphate groups. provides energy
NAD+ and FAD
nucleotides that help form atp
proteins
function as catalysts, defense, transport, support, movement, regulation, and storage. strands of amino acids
amino acids
20 in living organisms, linked by peptide bonds
oligopeptide
3-20 amino acids
polypeptides
21-199 amino acids
protein
more than 200 amino acids
glycoproteins
proteins with a carb attached (if on erythrocytes determine blood type)
