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NTS neurtransmitter, means by which nerve impulse crosses synapse; binds to surface of neuron, opens ligand gated channels for a particular ion LGC, permeability for a particular ion changes, and brings action potential to neuron

Ach = NTS that triggers muscle contractions
Excess Ach is broken down by cholinesterase
Norepinephrine - sympathetic neurons release it

Schwann cells - wrap around axons > myelin sheath
Node of Ranvier - b/w myelin s heaths

Saltatory conduction - jumping from nodes of ranvier, faster

CNS - brain, spinal chord
PNS

brain - cerebral cortex (largest part of brain, integrates all sensory input and voluntary motor activity), cerebellum (muscle coordination), hypothalamus (regulates homeostasis via hormones), medulla (regulates involuntary actions i.e. coughing, breathing)
Spinal chord - inner region - grey matter (dark cuz contains cell bodies)
outer region - white matter white cuz of myelinated axons
Spinal nerves which have both sensory and motor neurons, associated wtih spinal chord. Sensory neurons enter dorsal root, motor neurons exit ventral root

Peripheral NVS 2 parts
1. somatic NVS
2. autonomic NVS

ANS divided into sympathetic, parasympathetic
Sympathetic: heart beats faster
para: heart beats slower

Skin receptors: touch, pressure, heat, cold, pain, tension
Olfaction: odors
taste: sour, bitter, salty, sweet
Ear: Pinna, auditory cannal, timpanic membrane, malleous, incus, stapes
Cochlea, auditory nerve - chochlear nerve
Cochlea has hair cells sends impulses when sound waves come
Ear has 3 parts: external (auditory cannal)
middle (maleous, incus, stapes)
inner (cochlea, vestibular system - helps maintain balance, has hair cells that detect movement)

Eye
cornea, aqueous humor, pupil, lens, vitreous humor, light receptors, optic nerve
Iris = regulates size of pupil cillary muscle regulates shape of lens
Light receptors that has pigments - rod, cones (color)
rods = for poor lighting conditions

If nearsighted, light focuses in front of retina if object is far away
farsighted, light focuses behind retina when object is near

Skin = largest organ in body.

Genetics
Genetic info in DNA made of ATCG
Gene - codes for aspecific enzyme - which produces a trait; inherited by offspring
Exact location on a gene - locus; locus of gene pinpoints gene's physical place on chromosome
Homologous Xsomes, 2 genes sitting next to each other code for one particular trait = allele
Alleles can exist in slightly different forms.
Genotype

Mendel's law of Segregation
For any trait in a diploid parent cell, one allele for trait goes to 1 gamete, and other allele for trait goes to another gamete

Mendel's law of Independent Assortment
For any group of traist of a given organism, each trait will segregate independently during meiosis

Crossing over leads to genetic recombination

Hardy Weinberg Law
Even with all shuffling of genes that go on, individual alleles for traits stay overtime. Only applies to ideal populations-- these 5 conditions:

High # of indivdiuals
no mutations
no immigration/emmigration
random mating
any 1 gene has same chance of reproducing as any other

p^2 + 2pq + q^2 = 1
p+q = 1

Genetic drift: when population is small, some genes get lost overtime, and some genes become more frequent overtime

23rd chromosome: sex Xsome

XX- female
XY- male

Y Xsome can only be inherited from father.
Sex-linked traits - carried on the X chromosome usually

Population & Evolution

Gene pool - all genes in a population of one particular species
Genetic variability - gene pools have lots of diff alleles in them
this arises thru process of random mutation

Evolution - Due to ongoing random mutation, always will be genetic variability
At some time or other, some portion of population finds themselves in new enviroment. One gene in gene pool get an adv for those who have it - they will survive and reproduce in greather # than those who don't have that gene.

Speciation - creation of a new species. Results from prolonged evolution, 2 populations evolve seperately for a long time, will be different enough that they can't interbreed

Adaptive radiation - mutation t hat allows an adv compared to other individuals; produces new species

Speciation - over a long period of time, under certain conditions, new species can develop
Adaptive R, new species can arise from parent species by adapting to different ecological niche

hardy Weinberg law
in large population, gene pool tends to remain stable generation after generation

Genetic drift - in small pop, gene frequency drifts randomly

Kingdom Phylum Class Order Fmaily Genus Species

(king philip came over for great sex)

Comparitive anatomy

Chordates - phylum that includes invertebrates and vertebrates
Has 3 thigns: dorsal nerve chord, gill slits, notochord

vertebrates have 4 thigns:
vertebral column
closed circulatory system
developed nervous system
developed sensory apparatus

Symbiosis : 2 organisms that live together in close association
Mutualism - 2 organisms of diff species live close and help each other out
Commensalism - 1 organism benefits from another, other gets no benefit/harm
Parasitism - 1 organism feeds off another, does cause harm to other

Hund's Rule: you have to spread out orbitals singly until all orbitals in a subshell have 1 electron in them

Energy travels. One way is by wave of electromagnetic radiation: speed is 3 x 10^8 m/s in a vacuum. c = 3 x 10^8 (speed of light is an electromagnetic radiation)

wavelength = length of one full cycle of a wave: nm/cycle
frequency = f : # of cycles that passes by given point during 1 second
1/f = T : period of wave
Amplitude = height of wave maximun displacement from axis

Deroly's hypothesis: wavelength = h/mv

Matter, NRG

Energy comes from 4 fundamental forces of nature
1. Strong nuclear force - acts only b/w closely-packed protons/neutrons to bind them together to form atomic nuclei
2. Electromagnetic force - acts bw particles that possess electric charge
3. Weak nuclear force - conversion of neutrons to protons, and for conversion of protons to neutrons within nuclei
4. Gravitational force - attractive force b/w any two particles

Mass-Energy Equivalence
E = mc^2, c = speed of light 3x10^8 m/s


1 amu = 1.66 x 10^-27 => 1 kg = 6.02 x 10^26
1 eV = 1.6x10^-19 => 1J = 6.25 x 10^18

1g = 6.02 x 10^23 amu

1amu = 931 x 10^6 eV = 931 MeV
Difference in mass b/w free state and bound state is called mass defect of hte nucleus. It costs energy to bind the nucleus together

H with proton as well as neutron deuterium ; the nucleus itself is deuteron

Binding NRG = mass defect x 931 MeV / 1 amu
mass defect = mass of bound nucleus - mass of 3 separate nucleons

Nucleon = proton + neutron

mass number (A) = Z (# protons) + N (# neutrons)
Isotopes: same number of protons, but different number of neutrons

Half life
grams x (1/2)^t where t = # of halflife

Fission - when nucleus splits into 2 or more parts of comparable mass
Fusion - small nuclei combine into one larger nucleus

QUANTUM NUMBERS
Principal quantum number 'n'
n = electron's nrg level (n=1 ground state, n=2 next higher energy level, etc. On table of elements, means the rows)

Orbital quantum number 'l' (values of 0, 1, 2, 3... all values up to n-1)
l=0 (s orbital)
l=1 (p orbital)
l=2 (d orbital)
l=3 (f orbital)

Magnetic quantum number 'm l'
Can be any whole number from -l to l
i.e. if l = 2, m l can be -2, -1, 0, 1, 2

Magnetic spin quantum number 'm s' (values of +1/2 or -1/2)

ex: if n = 2, l can only equal 0, 1
when l = 0, m can only equal 0
when l =1, m can be -1, 0, 1
So for n = 2, there are 4 possible combinations of hte 3 quantum numbers
In format (n, l, m): (2, 0, 0) and (2, 1, -1), (2, 1, 0), (2, 1, 1)

RULE OF THUMB: n^2 orbitals for principal quantum number n
So when n =2, there are 2^2 = 4 possible orbitals

ex: How many possible combinations are there for 3p orbital? list the 3 quantum numbers.

n = 3
l = 1 (p orbital)
m can be = -1, 0, 1
3 possible combinations for 3p orbital: (3, 1, -1), (3, 1, 0), and (3, 1, 1)

ex: How many 6p orbitals are there?
3; the number of p orbitals for ANY nrg level (higher than n=1) is three.

Maximum number of electrons that can occupy energy level n is 2n^2.

i.e. how many electrons can fit in the n = 3 shell?
2 + 6 + 10 = 18, or 2(3)^2 = 2 x 9 = 18

i.e. how many e- can fit in n=5 shell?
2n^2 = 2 x 5^2 = 50 electrons

ELECTRON CONFIGURATION ABNORMALITIES
Cr / Mo follows this configuration:
Cr: [Ar]4s^1 3d^5 (3d subshell is half-filled)

Cu/Ag/Au follow this configuration:
Au: [Xe]6s^1 4f 14 5d^10 (5d subshell is filled)

VESPR Theory: Electron pairs, whether bonding or nonbonding, attempt to move as far apart as possible

An atom's geometric identity is based solely on its number of e- groups

# of electron groups / geometric family / hybridization
2 / linear / sp
3 / trigonal planar / sp^2
4 / tetrahedral / sp^3
5 / trigonal bipyramidal / dsp^3
6 / octahedral / d^2sp^3

-------------------
with 1 nonbonding pair of electrons

3 / bent
4 / trigonal pyramid
5 / see-saw
6 / square pyramid

----------------------
with 2 nonbonding pair of electrons

4 / bent
5 / T - shaped
6 / square planar

------------------------
with 3 nonbonding pair of electrons

5 / linear

Concentration rate = change in concentration of a reactant or product / change in time

Rate Law
A + B + C <---> D + E

rate = k[A]^n1^n2[C]^n3

Increasing temperature can increase rxn rate
A catalyst - substance that speeds up overall rxn, does this by:
1) lowering activation energy Ea
2) increasing number of properly-oriented collisions for hte reaction to proceed

Equilibrium constant = K = [C]^c[D]^d/[A]^a^b


Le Chatlelier's Principle
If a change is made to a chemical system in equilibrium, system will shift in a direction to fix it. (UNLESS you add something not in the equilibrium expression; i.e. adding pure solid or pure liquid, will not cause a shift)

3 ways to change a reaction equilibrium:
1) change concentration of reactant or product (will favor forward reaction if a reactant is increased)
2) change in pressure (will favor side w/ less moles and favor the reaction easing pressure)
3) change in temperature (adding heat will the endothermic rxn; if your reaction is exothermic and you add heat, will favor making reactants shift to left)

If a concentration is changed or pressure is changed, the equiplibrium will be shifted, but eventually it will settle down to the original value of K. If TEMPERATURE is changed, when the rxn reaches equilibrium it will do so at a DIFFERENT value of K.