levels or organization
atom-molecule-cell-tissue-organ-organ system-organism-population-community-ecosystem-biosphere
level one and def.
atom-non-living, building blocks of all substances
level 2 and def.
molecule-non-living, 2 or more atoms together/bonded
level 3 and def.
cell-smallest unit of life
level 4 and def.
tissue-cells organized to serve a collective function
level 5 and def.
organ-2 or more tissues that work together to serve a function
level 6 and def.
organ system-set of organs that work together to keep a body working
level 7 and def.
organism-an individual of one or cell
level 8 and def.
population-group of individuals of the same species in an area
level 9 and def.
community-all populations of all species in an area
level 10 and def.
ecosystem-a community plus its physical enviroment
level 11 and def.
biosphere-all regions of earth where organisms live
proton do what
determine type of atom (their no.)
neutron do what
atoms of same ele. can have dif. no. of neutrons (isotopes)
electrons do what
determines how atom bonds and reacts
amu =
atomic mass unit
what is the charge of most atoms
neutral porque they have the same number of pro and ele
if no. of pro and ele is unequal
ion
neg charge ion is called
anion
pos charged ion is called
cation
what is an ele.
pure substance made of atoms (all have same no. of p)
what is atomic no.
no. of p an atom has
mass no. is what
no. of n and p in an atom
what are isotopes named by
mass no.
bio is
the study of life (past and present)
how is life “defined”
complex, life emerges from interactions of simple parts
3 features of living things
requirement for ener and nutrients
homeostasis
use of dna as hereditary mat.
requirement for energy and nutrients
ongoing inputs of ener and nutrients sustain life
homeostasis
maintaining a stable internal enviroment
use of dna as hereditary mat
dna is passed to offspring during reproduction
what is a nutrient
substance an organism needs for growth and survival but cannot make itself
what are the 6 nutrients we need but can’t make
protein-mineral-carbohydrates-water-vitamins-fats
what nutrient can our body make
vitiman d w/ sunlight
2 categories of living things
consumers and producers
consumers
organisms that get ener and nutr by feeding on other organisms
producers
organ. make their own food using ener and mat in their enviroment (photo…)
growth
increase in no size and volume of cells
development
process by which first cell of a new organism becomes adult
reproduction
process by which parents produce offspring (sexual and asexual)
inheritance
transmission of dna to offspring
orbitals
spaces outside the nucleus
what fills orbitals
e
which orbital is filled 1st
the ones closest to the nucleus
if an e is further from the nuc it
has more energy
what do atoms want
to be stable/ want each level to be filled or empty
what do atoms do when a level isn’t full
they try to fill or empty it (chem reactivty)
level 1 and 2 max e
2 and 8
chemical bond
attractive force bet. 2 atoms
what is chemical bond due to
interactions bet. their e
electronegativity
measure of the ability of an atom to pull e away from other atoms
polarity
sep. of charges into + or - regions
what is polarity caused by
unequal sharing of e in a bond
types of chemical bonds
ionic and colvalent
what is an ionic bond
strong mutual attraction bet. ions of oppo. charges - each ion retains its own charge - ALWAYS POLAR
what is a colvalent bond
sharing of e between atoms - polar or non-polar (dependent upon eletronegativity of atoms in bond)
why is water polar
O is greedy and doesn’t want e shared equally
what r bonds shown as in a drawing
lines bet letter - no. of lines=no. of bonds - each line 2 es
solute
sub. dissolved in other sub.
solvent
sub. used to dissolve solute
what do acids release when dissolved
H^+
What do bases do
accept H^+ and release OH^-
what is the pH scale
used to measure how acidic or basic a substance is
about pH scale
0-14 - 0 Acid 14 Base
water is 7 and neutral
ex of acid
lemon-vinegar-wine
ex of base
bleach-soap-milk of magnesia
how many polar covalent bonds does water have per molecule
2
in water how are the charges separated
O is partially pos and H are partially neg
what does the separation of charges lead to
attraction bet water molecules
what are the attractions bet water molecules called
hydrogen bonds
what is a hydrogen bond
attraction bet a covalently bonded h atom and another atom taking part in a polar covalent bond
how strong i an h bond
5% of the strength of a covalent - individually weak collectively strong
what do h bonds do
stabilize DNA and proteins and give water its important prop
list the prop of water
good solvent - has cohesion and adhesion - high surface tension - less dense as a solid - high specific heat - high heat of evaporation
good solvent
dissolves anything polar or ionic
molecules that like water are called
hydrophilic
molecules that do not like water
hydrophobic
has cohesion and adhesion
cohesion - waters sticks to self
adhesion - water sticks to other molecules
high surface tension
due to waters high cohesion, makes surface resistant to rupture when placed under stress
less dense as a solid
most substances are more dense as solids than liquid but water is the opp. because its molecules are more spread out when frozen
high specific heat
takes more energy to increase waters temp compared to other liquids
high heat of evaporation
takes lots of energy to make water evaporate - used by animals to cool down