test one review Flashcards
linnaean classification system
Domain kingdom phylum class order family genus species
element
each of more than one hundred substances that cannot be chemically interconverted or broken down into simpler substances and are primary constituents of matter. Each element is distinguished by its atomic number, i.e., the number of protons in the nuclei of its atoms.
dependent group
MEASURED effect
the effect of temperature on hatching success
the hatching success is dependent variable
independent group
manituplated cause
the effect of temperature on hatching success
the temperature is the independent group!
cell theory
all organisms are made of cells and all cells come from preexisting cells
Pasteur’s classic experiment
Pasteur’s classic experiment
cells don’t arise by spontaneous generation.
Every living thing has “parents”
Evolution
is a change in time in a population indivuals dont cahnge
Natural Selection -
populations change b/c better adapted (fitter) individuals more offspring.
Think “Reproduction of the fittest” rather than just survival of the fittest.
Vestigial traits
uneeded things
widsom teeth in humans
legs in snakes and whales
Charles Darwin 1859
Proposed natural selection
as the mechanism of
adaptive evolution.
electron shells
1st shell holds 2 e-
2nd shell holds 8 e-
3rd shell holds 8/18 e-
in a double bond
4 electrons total
2 from each
in a tripple bond
6 total
3 from each
ionic bonds
atoms exchange electrons and become charged
giving the atoms a full charge
cation
atoms loses a election and becomes postive
anion
atom gains an electrons and becomes negative
covalent bonds
share pair of electrons
can be polar or nonpolar
nonpolar
atoms are shared equally
no charge given to these atoms
polar
aromsa are not shared equally and go towards the nucli with the most electronnegativity
giving the atom partial charge
o>n>c~=h
oxyen is the most electronneg of all elements
determined by the number of protons and the distance of the valence shell and the nucleus
if the electron is not sharred equally it will result in
one element have a partial postive or neg charge
like in water the O gains an electron so geta a partial neg charge and the H are lossing an electron so it gains a partial pos charge
van der waals interactions
hydrogen bonds are the strongest type
these do not make molecules they are only interactions between molecules or portions of molecules
hydrogen bbonds
opposites attract
when two water molecules approach each other the partial positive charge on hydrogen attracts each other the partial positive charge on hydrogen attracts the partial neg charge on the oxygen
water is polar
hydrophillic
water loving h
hydrogen bonding makes it possible for almost any charged or polar molecule to dissolve in water
hydrophobic
water fearing interactions with water are minimal or nonexistent they are forced to interact with each other
the hydrogen bonds will bond toether around the nonpolar hydrophobic molecules
cohesion
attraction between like molecules
ex water
meaning it stays together because of the hydrogen bonds between the molecules
also makes surface tenstion
adhesion
attraction between unlike molecules
interactions between a liquid and a soild surface
water ahderes to surfaces that have polar or charged components
surface tenstion
when the water molecules are at the top/surface there are no water molecules above for hydrogen bonding as result the exhibit stronger attractive forces between their nearest neighboring molecules this interaction between the surface water molceules results in tension that minimizes the total surface area
water resitst any force that increases its surace area
this is why its better to dive in the pool rather than belly flop
ice floats`
h-b bonds are stable
in water h-b are always braking and reforming
each water molecule participates in four hydrogen bonds these bonds form a repeating structure or crystal and the spce between the hydrogen bonds is more open then in a tight packed bond in the liquid form meaning there is more space between molecules so when frozen ice is less dense than water when heat is applyed the crystal bonds atart to break and the hydrogen bonds become closer making them more dense in the liquid form
specific heat
water has high specific heat beacuse when a source of energy hits it hydrogen bonds must be broken before heat can be transferred and the water molecules start moving faster
compounds are
molecules with more 1 atom type
ex h2o
bonding creates
new properties
oxygen needs
2
carbon needs
4
hydrogen needs
1
nitrogen needs
3
polar things stick to
other polar things
ex rainex is nonpolar so water runs right off
surface tension=
hydrogen bonds
salt=
water=
together =
solute
solvent
solution
oil and water
oil is nonpolar so it cant disslove
water is polar
dissociation of water caused by chemical reactions
O tends to steal H ions from other O and they do back and forth
creathing hydronium ion and hydroxide ion
hydronium ion
h30+pos
hydroxide ion
oh- neg
sweating
the water molecule absorb a get deal of engery before they evaporate so you loose heat
water is not completely stable because
the h-b are always breaking and reforming
substances that give up a proton/ hydrogen ion during chemical reacations and raise the hydronium ions (cation h30)concentration of water
acids
molecules or ions that acquire protons during chemical reactions lowering the hydronium ion concentractionof water
bases
a chemical reaction that involes a transer of protons is called
a acid-base reaction
every acid base reaction must have a proton donor and acceptor and acid & base
hydroxide ion oh- is an
anion held together by covalent bond and has a neg charge and functions as a base
dissociation
the process inwhich ionic compunds spearate or split into smaller particles ot ions
acids
give up protons and raise the hydronium ion concentration h3o+
lower ph of a solution by adding h+ to it
bases
acquire protons and lower the hydronium ion
takes the 3rd h ion
raise ph of a soultion by either removing h+ or adding oh-
mass
can not be created or destroyed but may be rearranged through chemical reacations
endothermic
within heating heat is absorbed during the process
liquid->gas
exothermic
outside heating releases heat
gas–> liquid
acidic solution
low ph < 7
low oh- hydroxie ion
high h+ hydrogen ion
base solution
high ph >7
high ou- hydroxie ion
low h+ hydrogen
h+ proton binds with water to make
hydronium ions h3o+
buffer
are an acid base team that resists change in ph
carbon can form
4 covalent bonds
this results in an almost limitless array of cominations by double single and tripple bonds
carbon atoms
form the sturctural framework for most of the important compunds in life minus water gives molecules its over all shape
molecules contain carbon bonded to other elements such as hydrogen are called
organic molecules
functional groups 6
include h-,n-,o-,p-,s-
funcational groups that has oh is called
hydroxly group
found in alcohols
highly polar so makes compunds more soluble through h-b with water may also act as a weak acis and drop a proton
isomers
can have the same molecular formula but have different strurutal formula
struture=funcation
carbonyl group
found in straight sugars fatty acids on aldehyde and ketone molecules the place the carbon double bond to oxygen detrimines if its a aldehyde or ketone
if placed in the middle its ketone
placed at the end/start its aldehyde
the site of joining to make biger molecules(aldehydes)
carboxyl group
acts as a acid tends to lose a proton
carbon double bonded to oxygen and same carbon linked to oh
found in fatty acids and amino acids
polar
amino group
found in amino acids nucleotides
acts as a base to attract a proton
nitrogen boned to 2 diff h
polar
sulfhydryl group
when present in proteins can form disulfide s-s that contribute to protein structure add an sh to the carbon
phospahate group
molecules with more than one phosphate linked together store large amounts of engery found in nucleic acids and atp
one phospahatre ion surrounded by 2o- and 2o+
