asexual reproduction
reproduction done with only one parent cell
sexual reproduction
reproduction done with two parent cells (sperm and egg)
autotroph
organism that makes its own nutrients from the sun
heterotroph
gets energy by consuming nutrients from the enviornment
natural selection
the process through which populations of living organisms adapt and change
unicellular
one cell (ie. bacteria, yeast)
multicellular
more than one cell (ie. animals, plants)
atom
basic unit of a chemical element (ie. oxygen)
molecule
a group of atoms bonded together (ie. H₂O)
proton
located in the nucleus of an atom; positive charge
electron
circles around an atom; negative charge
covalent bond
atoms “sharing” outer electron with another atom
ions
a charged atom or molecule (charged because the # of electrons do not = the # protons)
hydrogen bond
the attraction between partially (+) H of one H₂O molecule and the (-) O of another molecule
cohesion
hydrogen bonding between water molecules
adhesion
when water attracts to other polar or charged particles
polar
electrons between molecules are shared unequally
nonpolar
electrons between molecules are shared equally
amphipathic
molecules that have both a nonpolar and polar region
independent variable
variable in an experiment that is changed (ie. using different types of fertilizer between plants)
dependent variable
variable in an experiment that is affected by the independent variable (ie. result of using different fertilizer between plants)
controlled variable
the variable that doesn’t change (ie. color of the plant pot)
where are each of the three subatomic particles located?
protons (+) and neutrons (o) are inside the nucleus; electrons (-) are swirling around it
explain how an ion is different than an atom
atom= has no electrical charge
ion = has electrical charge due to an unequal amount of protons and electrons (more protons means its positive, more electrons mean negative)
what happens when ions of the same charge get close to each other
repel each other
what happens when ions of opposite charges get close to each other?
they attract each other; form ionic bond
what is the HONC1234 rule
Hydrogen = 1 covalent bond
Oxygen = 2 covalent bonds
Nitrogen = 3 covalent bonds
Carbon = 4 covalent bonds
what’s the difference between a polar and nonpolar covalent bond
-polar covalent bonds have unequally shared electrons
-nonpolar covalent bonds have equally shared electrons
how is a hydrogen bond different from a covalent bond
hydrogen bonds form between two H₂O molecules
covalent bonds form within any molecule
describe how the properties of water (hydrogen bonding, cohesion, adhesion) result from the polar structure of a water molecule
-cohesion is when water molecules attract to other water molecule which makes hydrogen bonds (the hydrogens attach to oxygen atoms)
-adhesion is when water molecules attract to either polar or charged molecules
explain the difference between acids and bases based on their position on the pH scale
pH 0-7=acid
pH 7-14 =base
explain why buffers are important to a living organism, what characteristic of life do they directly influence the most?
they are important because they neutralize excess acids or bases to keep the pH of a solution stable
they maintain a stable pH in blood, extracellular fluids, etc.
capillary action
ability of water to move upwards in small tubes or narrow spaces (both cohesion and adhesion are responsible for this)