Studied by 17 PeopleTags & Description
Ch 1 : What is biology
Study of life
Cell Bio : study of cells
Molecular Bio : study of biology at a molecular level
ch 6 : centrosomes and centrioles
ONLY FOUND IN ANIMAL CELLS
centrosome is a cellular structure involved in the process of cell division.
a centrosome is made up of 2 centrioles
ONLY FOUND IN ANIMAL CELLS
Ch1 : what is science
Knowledge of natural world through observations and experiments
Ch 1 : 7 Characteristics of life
Order (cells)
Adaptation
Regulation
Response to Environment
Growth and development
Energy processing
Reproduction
Ch 1 : Inductive reasoning vs deductive
Inductive : specific to general
deductive : general to specific
Ch 1 : hypothesis
DIFFERENT FROM A THEORY
Educated guess / proposed explanation
If .. then logic
Testable : through observations and experiments
Falsifiable : can’t be fully proved
Ch 1: controlling for variables
Minimize affect on on dependent ( what you’re measuring ) to not draw incorrect conclusions on independent
Ch 1 : independent vs dependent
Independent: manipulated by researcher
Dependent: being measured , based on independent’s effect
Ch 1 : theory
theory : Explanation that is less specific than a hypothesis
generates new hypothesis and is supported by way more evidence than a hypothesis
Ch 1 : theory differences from hypothesis
A theory is :
broader in scope ( umbrella ; hypothesis grouped under )
evidence based
current ( changes as new info is presented )
doesn’t have to be testable
Like a hypothesis it can be proven and rejected
Ch 2 : what is an element
element : substance that can’t be broken down to other substances by chemical reactions
cannot be broken down w/o losing its identity
example :sodium
Ch 2 : Key elements
key elements : carbon , hydrogen , oxygen and nitrogen
Ch 2 : Compounds
compound : 2 or more elements combined in a fixed ratio
compounds have different properties than when they are in their element form
example : table salt
ch 2 : what determines properties of an element
the structure of its atoms ( protons , neutrons , electrons : electrical charges and locations )
example : oxygen has 8 protons , neutrons , electrons
ch 2 : what is an atom
atom : smallest unit of matter that still retains properties of an element
atoms in a column of periodic table In same column behave the same
ch 2 : subatomic particles that make up atomic structure
Neutrons : no charge neutral ( found in nucleus )
Protons : + charge ( found in nucleus )
Electrons : - charge ( found moving around protons and neutrons )
electrons are smaller than protons and neutrons
Ch 2 : atomic number vs atomic mass
Atomic number
protons ( changing the # of p changes identity )
Atomic mass
protons + neutrons
unit : amu ( atomic mass unit )
Ch 2 : electron orbitals
orbitals have 2 electrons
each electron shell has a different number of orbitals
different shells have different energy
orbitals are 3d shapes where electrons hang out
Ch 2 : energy
energy : potential to cause change
ch 2 : potential energy and electrons
Potential energy : energy due to location
The closer the electrons are to the nucleus, the lower the energy level. The farther the electrons are to the nucleus, the higher the energy level.
ch 2 : valence and valence electrons
valence : # that shows how well atom can combine w/other atoms through covalent bonds
is determined by valence electrons : which are the outermost electrons
ch 2 : full valence shells
a full valence shell causes an atom to become unreactive
the goal of every atom is to have a full valence shell which they can gain through covalent bonding (sharing electrons) or ionic bonding ( transferring electrons )
when an atom is reactive it either gives or takes electrons
ch 2 : Isotopes
Isotopes : atom with the same # of protons and electrons as other of same elements but has a different amount of neutrons ( causes a different atomic mass )
even with diff atomic masses they behave the same in chemical reactions
ch 2 : chemical bonds and how they form
chemical bonds are attraction between two atoms from covalent ( sharing electrons ) or ionic (transfer electrons ) bonds
only valence electrons can participate in chemical reactions ( interactions with other atoms )
Ch 2 : Ionic bonds
transfer of valence electrons
one atom is more electronegative
transfer creates ions ( charged particles ) of different charges
anions ( - charged ) ( have more electrons than protons b/c they gained electrons )
cations ( + charged ) ( have more protons than electrons b/c they lost electrons )
Opposites attract : Cations and anions are attracted to each other
the strength is affect by environment : ionic bonds become weak in cells
between atoms
Ch 2 : covalent bond
sharing of valence electrons (custody agreement )
can be polar ( one parent hogs kids )
can be non polar ( parents share kids equally )
Polar : one atom is more electronegative than other = atom with higher electronegativity hogs electrons
Non polar : both atoms have a similar electronegativity and share electrons equally
is between atoms
ch 2 : molecule
2 or more atoms held by a covalent bond ( sharing electrons)
ch 2 : what does it mean to be electronegative
have more strength to pull electrons
ch 2 : hydrogen bonds
weak chemical bond . formed when slightly positive hydrogen atom of a polar covalent ( unequal sharing ) in one molecule is attracted to a negative atom of a polar covalent bond .OPPOSITEs attract ( + and - )
this bond is between whole molecules
ch 2 : strong bonds vs weak bonds
strong bonds : needs a lot of force to break and to make
covalent and ionic
weak bonds : easily breakable and easy to make
hydrogen and van der waals
ch 2 : what determines the shape of a molecule
the bonds between the atoms in a molecule determine the molecules shape . the bonds are determined by valence electron arrangement
changing shape alters function ( think of a key )
ch 2 : what happens to matter as chemical reaction occurs
Matter is rearranged as chemical bonds are made and broken
Matter ( energy ) is not destroyed
all atoms have to be on both sides in chemical equations
most reactions are reversible
ch 2 : chemical equilibrium
Point where forward and reverse reactions occur at same rate causing concentrations to stop changing
equal rates of reactions
ch 2 : van der Waals
regions of + and - charge ( even in non polar covalent bonds)
allows atoms and molecules to stick together
Ch 2 : Amphipathic molecules
part polar (hydrophilic ) and part non polar (hydrophobic) ; polar parts attract to water and non polar rejects
phospholipid bilayer
Ch 3 : Chemical structure of water
H20
oxygen is more electronegative ( hogs electrons , partial neg charge ) than hydrogen ( partial pos charge )
Ch 2 : non polar molecules
non polar covalent bonds ( sharing electrons equally b/c of similar electronegativity ) are hydrophobic
don’t like water
ch 2 : polar molecule
polar covalent bonds ( one atom has more elctronegativity and hogs electrons ; not sharing equally ) are hydrophilic
they do like water
ch 3 : water’s internal and external bonds
internal polar (hydrophilic ) covalent ( no equal sharing b/c oxygen is more electroneg. ) causes external hydrogen bonds ( - and + molecules attract )
ch 3 : water bonding with water (cohesion )
When water bonds with water it causes hydrogen bonds ( - and + polar covalent in a molecule attracted to each other )
this is called cohesion
ch 3 : how does water’s ability to form hydrogen binds affect it’s properties
allows for cohesion (hydrogen bonds holding together )
high surface tension (difficultly breaking surface of a liquid )
adhesion (water bonding to something else )
floating of ice on water ( water is more dense as a solid than liquid )
ch 3 : properties that result b/c of water’s polarity (hydrophilic - attracted to water )
cohesion
ice floating on water ( spread out b/c hydrogen bonds )
water being a solvent ( dissolving agent )
ch 3 : how does a high specific heat and high heat of vaporization impact cells ? Organisism
Water resists temp changes b/c of hydrogen bonds . Heat absorbed by water is used to break hydrogen bonds and release heat
bodies of water moderate temp , organisms resist temp change , evaporative cooling allows temp stability for organism regions and planet
ch 3 : specific heat
amount of heat absorbed or lost to change temp
ch 3 : heat of vaporization
quantity of heat required to change from liquid to gas
ch 3 : soultion
liquid that is a homogeneous ( evenly distributed ) mixture of two or more substances
H +
hydrogen ion
OH -
hydroxide ion
ch 3 : why does ice float on water
water is less dense as a solid than liquid
water expands as it solidifies
hydrogen bonds lock into place as water freezes
ch 3 : what kinds of molecules can water dissolve
Ions ( - and + )
Polar ( unequally sharing , hydrophilic )
Ionic compounds ( transferring of valence electrons ) (salt)
covalent polar ( sugar )
large molecules w/polar/ionic regions
ch3 : adhesion
water sticks to something else ( charges or partial charges )
allows plants to transport h2o
ch 3 : cohesion
water sticks to water , linking of like molecules by hydrogen bonds
allows plants to transport h20
causes high surface tension
ch 3 : solvent
dissolving agent of solution
example : water
ch 3 : solute
substance dissolved in solution
ch 3 : hydrophilic
water loving ; polar ( don’t share e equally ) won’t always dissolve , attracted to water molecules
ch 3 : hydrophobic
water fearing ; non polar ( share electrons equally ) hydrogen carbon bonds
Ch 3 : dissociation of water
hydrogen ion (h+ ) moves to another water molecule leaving its electron behind
ch 3 : 3 characteristics of dissociation of water
reversible
rare
reactive hydrogen ion
ch 3 : acids
substance that increases hydrogen ion concentration
donates a H + (hydrogen ion )
more hydrogen (H+ ) than hydroxide (OH-)
ex: Hydrochloric acid
ch3 : bases
substance that decreases hydrogen ion concentration
accepts H + (hydrogen ion )
less H + than OH - ( hydroxide )
Ch 3 : PH SCALE
Numerical method for expression range of hydrogen ion in concentrations
0 to 14
7 is neutral ( equal amount of hydrogen ion to hydroxide )
small # more acidic
ph changes molecular structure
ch 3 : strong and weak acids and bases
strong
acids and bases completely ionized ( break apart) when dissolved in water
dissociate completely ( break apart )
shown with single arrow
weak
partially dissociates ( partially break apart )
shown with double arrow
dissociation is a chemical reaction where a compound breaks into two or more parts.
Ch 3 : Buffers and how they work
buffers are substances that minimize changes of hydrogen and hydroxide ions
accepts hydrogen (h + ) when there’s too much and donate hydrogen when there not enough
ch 4 : how does carbon bond
carbon has 4 valence electrons
forms single or double covalent bonds ( sharing custody )
carbon based molecules have structural diversity
Ch 4 : Isomers
Compounds w/ the same # of atoms of same elements , have different structures which cause different properties
equal parts different properties
same molecular formula - diff structure - diff properties
Ch 4 : Structural isomers
same formula , different arrangement
covalent bonds b/w atoms
more possible structural isomers as molecule gets bigger
ch 4 : cis - trans isomers
arrangement of functional groups in relation to double bonds (or sometimes rings)
Cis : the two are on the same side
Think of sisters
Trans : the two are on opposite sides
different shapes = different functions
ch 4 : enantiomers
mirror images ( left and right hand )
different shapes = different functions
right handed molecule won’t fit into left handed molecule spot
functional groups
specific groups of atoms that affect molecular function by being directly involved in chemical reactions.
Hydroxyl (-OH )
Alcohols
Names end in -ol
Polar ( hydrophilic )
Forms hydrogen bonds with water molecules ( dissolve in water )
Carbonyl ( C=O)
•Sugars
names end in -oses
polar
Two types
Ketone- carbonyl in the middle
Aldehyde- carbonyl at the end
Carboxyl ( - COOH)
Acts as an acid because of the polar covalent bond between O and H
(-) charged
Found in cells as the carboxylate ion
Amino ( - NH2 )
Acts as a base (+) charged
Found in cells in ionized form
Amino acids have a carboxyl group and an amino group
Sulfhydryl ( -SH)
Cross links: two sulfhydryl groups can bond covalently which stabilizes protein structure
polar
Phosphate ( -OP3)
Acts as an acidic
(-) charge
hydrophilic
Methyl (-CH3)
Isn’t a functional group b/c its not reactive
Acts as a tag
Affects gene expression when bound to DNA
Affects shape and function of molecules, like sex hormones
NON POLAR
Ch 4 : ATP and its purpose
Adenosine triphosphate
“molecular currency”
Transports chemical energy within cells
transfer of energy b/w molecules
Ch 5 : Macromolecules
macromolecules are giant polymers formed by joining of small monomers ( train cars )
monomers linked by covalent bonds
Ch 5 : dehydration synthesis
water is lost to form a bond b/w 2 molecules
Water is taken away to make something new
ch 5 : hydrolysis
water is gained to break a bond and form two molecules
breaking down into small parts
Ch 5 : how are polymers covalent bonds formed and broken ?
Monomers connected by dehydration reaction (water is lost to form a bond b/w 2 molecules )
Polymers broken by hydrolysis (water is gained to break a bond and form two molecules)
Ch 5 : enzymes
enzymes are
macromolecule
end in -ase
catalyst (increase rate of reaction)
proteins
Ch 5 : cataylst
Facilitates reaction but is not consumed by reaction
Ch 5 : carbohydrates
sugars that end in -ose
Carbon, hydrogen, oxygen
Carbonyl group
monomers : monosaccharides
