Chapter 2 Flashcards
elements
basic unit of matter
atoms
smallest unit of element that retains property of that element
what makes up atoms
protons, neutrons, electrons
ions
atoms that have lost or gained one or more electron
isotopes
have an extra neutron in the center of the atom
radiation
energy given off by certain chemical elements when they break down into other elements , usually unstable isotopes
what is radiation used in
medical imaging & to kill cancer cells
chemical bonds
hold molecules together
covalent bond
atoms share electrons
ionic bonds
opposite charges attract
hydrogen bonds
weak attraction, partial charges
water is essential to
all life
water is important because
adhesion, cohesion, it is a good solvent, it splits into h+ and oh- and it has a high specific heat
adhesion
water sticks to other things
cohesion
water sticks to itself
solvent
dissolves lots of stuff, not everything though
specific heat
how much energy it takes to raise 1 g of substance by 1
pH is the measure of
H+ in a solution
acids release ____ when added to water
H+
bases release _____ when added to water
OH-
the pH scale goes from
0-14
on the pH scale 0 is
acidic
on the pH scale 14 is
basic
buffer
substance that does chemical reactions in water to keep pH constant
what exactly does a buffer in water do
remove or add H+ depending on what chemical is present
what are the major molecules of life
carbohydrates, lipids, proteins, nucleic acid
Carbohydrates
molecules of carbon, hydrogen and oxygen that provide energy
types of carbohydrates
monosaccharides, disaccharides, polysaccharides
monosaccharides
simple sugars such as glucose
disaccharides
two simple sugars joined together, sucrose or lactose
polysaccharides
long chains of simple sugars joined like glycogen or cellulose
lipids
non polar molecules that don’t dissolve in water
types of lipids
triglycerides, phospholipids, steroids
triglycerides
three fatty acids bound to one glycerol
dietary fats/oils
saturated-no double bonds
unsaturated-double bonds between carbons
what is the role of triglycerides in humans
long term energy storage, protection & insulation
phospholipids
2 fatty acids & 1 phosphate bound to one glycerol
hydrophilic and hydrophobic ends to molecule
main component of cell membrane
steroids
characteristic 4-ring carbon backbone
cholesterol - important in membrane
sex hormones are steroids
proteins
made of amino acids
how many different types of amino acids are there
20
what type of bond joins amino acids together
peptide bonds
primary structure of protein
order of amino acids in chain
secondary structure of protein
bending & coiling of chain
tertiary structure of protein
3-D folding
quaternary structure of protein
joining of multiple chains
what is the main role of proteins
catalyze reactions; enzymes
also used for structural support, transport, and movement
what is the base unit of nucleic acids
nucleotide
nucleotide
phosphate group, 5c sugar and nitrogenous base
DNA
two strands (double helix), sugar=deoxyribose, n bases=cytosine, adenine, guanine, and thymine
what holds n bases together
hydrogen bonds
RNA
single strand, sugar=ribose, n bases are cytosine, adenine, guanine, and uracil
DNA is the
blueprint of life
RNA is part of
the translation process-interpreting DNA into proteins
what catalyzes the reactions that build structure and do processes
protein enzymes
ATP
adenosine triphosphate, nucleotide of adenine, ribose & 3 phosphate groups
P bonds easy to make and break
give energy to reactions that need and capture from reactions that release
