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576 Cards in this Set

  • Front
  • Back
tight junction
no intercellular space
gap junctions
link together cytoplasm of adjacent cells. consist of protein channels that allow ions to flow through freely.
desmosomes
plaque-like proteins embedded in the cell membrane to which the cytoskeleton is attached. responsible for structural integrity of tissue. hold cells tightly together.
peroxisomes contain...
catalase, an enzyme relevant to the processing of hydrogen peroxide.
inner mitochondrial membrane is folded into convolutions called...
cristae
interior of the inner mitochondrial membrane is termed the...
matrix
plastids
contain pigment and function in photosynthesis
cilia and flagella are composed of...
microtubules
centrioles are composed of...
microtubules
the cytoplasm is composed of...(2 things)
microtubules and microfilaments
microtubules are composed of...
tubulin
microfilaments are composed of...
actin
commensalism
a relationship in which one organism benefits but the other is neutral
mutualism
a relationship in which both organisms benefit
hemizygous
having only one copy of a gene rather than the normal two copies. sex chromosomes.
homologous
the 22 pairs of non-sex chromosomes. Have 2 copies of the chromosome. autosomes.
nucleosomes
the visible units of the histone
nucleic acids (DNA, RNA) are bound in a strand by what kind of bond?
phosphodiester bonds
antiparallel orientation
one strand runs from 5' to 3', while the opposite runs from 3' to 5'.
DNA replication begins at the...
origin of replication
origin of replication
a specific sequence of nucleotides that are the signal to start DNA synthesis
helicase
unwinds the DNA strands
replication bubble w/ 2 replication forks
the part of the DNA where the strands have been separated by helicase. The daughter strands begin to form in it.
DNA polymerases
synthesize the new strand of DNA. Read template in 3' to 5' direction and synthesize DNA in the 5' to 3' direction.
primase
lays down short RNA primers so DNA polymerase can begin.
semiconservative
describes DNA replication, b/c each of the newly formed molecules contains half of the original DNA molecule.
semidiscontinuous synthesis
the production of a nucleotide chain via Okazaki fragments.
joins Okazaki fragments
DNA ligase
template / non-coding / anti-sense strand
the DNA strand that serves as a template and is actually read and transcribed in mRNA synthesis
RNA polymerases
function in transcription
sigma factor
binds RNA polymerase to the DNA template
promoter
where RNA polymerase binds DNA. determines which DNA strand is the template, where transcription starts, and the direction of transcription.
start site
where transcription begins. the last position of the promoter site.
Pribnow box
common to all promoters. the sequence TATAAT at or near the -10 position.
consensus sequences
common to all promoters. Refers to the Pribnow bow and to the TTGACA sequence at the -35 position
transcription unit
the length of the molecule from promoter site to terminator. Includes the promoter site, the sequences that are transcribed, and the terminator.
the four steps of transcription:
1) template recognition
2) initiation
3) elongation
4) termination
the nucleotides that begin at the template are...
ribonucleoside triphosphates (NTPs)
the creation of a phosphodiester bond causes the release of...
pyrophosphate (PPi)
initiation is complete when...
the sigma factor detaches from the RNA polymerase
process of initiation (5 steps):
1) 2 nucleotides approach DNA template
2) temporary hydrogen bonds form --> DNA-RNA hybrid
3) RNA polymerase catalyzes formation of phosphodiester bond
4) NTPs added
5) sigma factor detaches from RNA polymerase ---> initiation complete
process of transcription (4 steps):
1) binding of RNA polymerase to promoter on DNA
2) unwinding of DNA
3) positioning of 2 nucleotides
4) formation of phosphodiester bonds
the region of unwinding of DNA is called the...
transcription bubble
hairpin loop
created by a large number of G-C sequences followed by several U residues (GCGC...UUU).

the GC sequence folds in on itself to create a loop.

this causes the RNA polymer to slow or pause. the remaining AU sequence breaks apart easily, terminating RNA synthesis
rho factor
causes the RNA-DNA hybrid to unwind, terminating RNA synthesis.
RNA polymerase I
synthesizes rRNA in eukaryotic cells
RNA polymerase II
synthesizes mRNA in eukaryotic cells
RNA polymerase III
synthesizes tRNA in eukaryotic cells
control sequences
modulate the efficacy of eukaryotic promoters
the consensus sequence in eukaryotic cells
the TATA box, located 30 base pairs upstream of the start site
4 differences btwn transcription in bacteria and in eukaryotic cells
1) site of transcription
2) types of RNA polymerase
3) nature and complexity of promoters
4) presence of transcription factors
5) processing (spicing, 5' cap, poly A tail)
transcription factors
proteins that bind w/ the DNA promoter site and interact w/ one another to facilitate the binding of the polymerase to the promoter. only in eukaryotic cells.
primary transcriptase / hnRNA
an mRNA molecule freshly produced by transcription in eukaryotes. not functional; a precursor to a functional RNA molecule.
three steps of RNA processing
splicing, 5' end modification, 3' end modification
5' end modification --> 5' cap
5' end binds to guanine by 5' - 5' linkage.

guanine unit undergoes methylation, methylated guanine residue becomes molecule's 5' cap.
poly A tail
a long run of adenine residues added at the 3' end of the mRNA
5 steps of translation
1) ribosome recognizes mRNA and binds
2) ribosome reads mRNA, three nucleotides at a time
3) each codon orders a particular amino acid to be brought to the ribosome
4) tRNA w/in cytosol bring amino acids to ribosome
5) amino acids form peptide bonds to form polypeptide
codon
3 nucleotides
two subunits of a prokaryotic ribosome
one large (50S) and one small (30S)
three binding sites of tRNA
A site, P site, E site
polyribosome
in both prokaryotes and eukaryotes, many ribosomes synthesizing the same protein simultaneously associate w/ one another
two functional sites of tRNA
anticodon and amino acid acceptor site
anticodon
sequence of three nucleotides. where mRNA binds to the tRNA.
amino acid acceptor site
where tRNA binds to an amino acid.
aminoacyl-tRNA synthetase
recognizes the tRNA carrier and the amino acid to which it is specific.

Recognition btwn tRNA and amino acid, therefore, is mediated not by tRNA, but by the relevant aminoacyl-tRNA synthetase.
aminoacyl-tRNA
produced when a tRNA and an amino acid are bound together

tRNA^(name) when unbound,
(name)-tRNA^(name) when bound to amino acid
amino acid activation
the binding of an amino acid to its tRNA to produce the corresponding aminoacyl-tRNA

an endergonic reaction (delta G is positive) involving the cleavage of two high-energy phosphate bonds

amino acid + ATP + tRNA --> aminoacyl-tRNA + AMP + PPi
3 phases of translation:
1) initiation
2) elongation
3) termination
translation involves reading the mRNA transcript from...
5' to 3'
5' untranslated region (5' UTR)
contains upstream regulatory sequences that are essential for initiation
3' untranslated region (3' UTR)
contains downstream regulatory sequences that help w/ termination
start codon
the first AUG codon on the mRNA
initiation complex
the small ribosomal subunit (30S), fMet-tRNA^(Met), and molecule of mRNA
3 steps of initiation of translation:
1) 30S subunit binds to 5' end of the mRNA transcript
2) UAC anticodon of fMET-tRNA^(Met) binds AUG start codon on mRNA
3) large ribosomal subunit joins initiation complex to form 70S ribosome
4 steps of elongation of translation:
1) mRNA codon exposed at A site of codon
2) aminoacyl-tRNA arrives at A site and forms hydrogen bonds w/ codon. Step requires hydrolysis of GTP.
3)peptidyl transferase transfers amino acid in P site from tRNA carrier to amino terminus of aminoacyl-tRNA in the A-site. Peptide bond formed.
4) Ribosome translocates 3 nucleotides along mRNA in 5' to 3' direction. This moves polypeptide to P site, old tRNA to E site, and exposes next mRNA to A site. Requires hydrolysis of one GTP.
E site
always contains a tRNA that has lost its amino acid to the growing peptide chain.
P site
always contains a tRNA hydrogen bonded to the mRNA transcript, and this anchors the peptide chain to the ribosome.
A site
always where the next aminoacyl-tRNA arrives
it costs _____ phosphate bonds to add an amino acid to fMet
4. 2 bonds to join tRNA w/ amino acid, 1 to bring aminoacyl-tRNA into A site, 1 to translocate the ribosome so the next codon can be read.
stop codons
UAG, UGA, UAA (U Are Gone, U Go Away, U Are Away).

Do not code for tRNA molecules. Their arrival at A site causes release factors (proteins) to stop elongation and to release polypeptide.
release factors
stop the elongation process
codon
a series of three mRNA nucleotide units recognized by complementary tRNA nucleotide units
prokaryotic ribosomal subunits
30S and 50S. 70S ribosome.
eukaryotic ribosomal subunits
40S and 60S. 80S ribosome.
nucleolus
where rRNA and ribosomes are synthesized
Shine-Dalgarno sequence
A common 5' UTR (untranslated region) in prokaryotes.
Kozak sequence
a common 5' UTR in eukaryotes
5' UTR
functions in assembly of the translation initiation complex
first amino acid in prokaryotes
fMet-tRNA
first amino acid in eukaryotes
methionine (Met-tRNA, not fMet-tRNA)
differences in timing of transcription and translation in eukaryotes vs. prokaryotes
transcription and translation occur simultaneously in prokaryotes, but not in eukaryotes b/c they occur in different places

eukaryotes must undergo mRNA processing
genetic code
the association btwn each mRNA codon and the amino acid for which it codes
degenerate
the genetic code does not represent a 1-to-1 codon-amino acid ratio; any given amino acid might be coded for by more than one mRNA codon
transcription unit
the portion of a DNA molecule that undergoes transcription, from promoter site to terminator
diploidy
the state in which every chromosome of a cell has a homologue. 2N.
haploid
the state in which chromosomes lack a homologous counterpart. 1N.
centromere
where each pair of duplicate chromosomes is joined.
sister chromatid
each member of the chromosome pair
aster fibers
star-shaped fibers that form around the centrioles.
prometaphase (early metaphase) is marked by...
complete dissolution of the nuclear membrane
kinetochore
the protein structure on chromosomes where the spindle fibers attach during cell division to pull the chromosomes apart.
metaphase
chromosomes align on the metaphase plate so that centromeres line in a plane at the cell's midpoint.
anaphase
sister chromatids separate and move toward opposite poles of the cell.
daughter chromosome
separated sister chromatids
telophase
daughter chromosomes are positioned at opposite poles of the cell, and the kinetochore fibers disappear.

Nuclear membrane forms around each set of daughter chromosomes.

chromosomes condense. nucleoli reappear.
prophase
chromosomes condense. nucleolus disappears. centrioles move to opposite poles of the cell. aster fibers form around centrioles. mitotic spindle forms and nuclear membrane dissolves.
cytokinesis
begins during end of anaphase or beginning of telophase.

cleavage furrow forms at center of cell, dividing cell.
reduction division
the generation of haploid daughter cells by a diploid parent cell. accomplished by meiosis.
tetrads
homologous pairs of duplicated chromosomes align in proximity to one another. occurs in prophase I of meiosis.
synapsis
the association of homologous pairs of duplicated chromosomes to form a tetrad
chiasma / synaptonemal membrane
the site at which crossing over occurs
meiotic metaphase I
PAIRS of homologous chromosomes align on the spindle apparatus
meiotic anaphase I
homologous chromosome pairs separate and move to opposite poles of the cell. Centromeres DO NOT split.
spermatogenesis occurs in the ______
seminiferous tubules
zygote
diploid cell resulting from the fusion of a sperm and ovum
spermatogonia
relatively undifferentiated cells w/in the seminiferous tubules of the testes
primary spermatocyte
b/f first meiotic division
secondary spermatocyte
after first meiotic division, b/f second meiotic division.
spermatids
haploid. Result from second meiotic division of secondary spermatocytes
epididymis
a coiled tube that serves as the site of maturation and storage for sperm
acrosome
part of sperm filled w/ degradative enzymes that facilitate penetration of the ovum during fertilization
order of structures through which sperm travel
seminiferous tubule, epididymis, vas deferens, ejaculatory duct, urethra
ootid
haploid. an immature ovum.
oogonium
the diploid precursor to the ovum.
follicle
the ovum and supporting cells
ovulation
a follicle ruptures, releasing the ovum, which then enters the fallopian tubes
fallopian tube
connects the ovaries and the uterus. normally the site of fertilization.
outer membrane of the ovum
corona radiata
inner membrane of the ovum
zona pellucida
fertilization
sperm releases enzymes from its acrosome, which degrade the corona radiata and zona pellucida

fertilization is complete when sperm and ovum nuclei have fused to form the zygote
endometrial tissue
the lining of the uterus. the site of implantation.
placenta
develops at the site of implantation.

the site of the transfer of nutrients from the mother to fetus as well as waste products from fetus to mother.
order the developmental stages the embryo passes through
zygote, cleavage, morulation, blastulation, gastrulation, germ layer formation, neurulation
cleavage
a series of rapid cell divisions
morula
when the developing organism consists of ~32 cells
blastula
a hollow ball of cells
blastocoel
the fluid-filled center of the blastula
gastrulation
invagination of the blastula to form a gastrula
________ marks the beginning of morphogenesis
invagination
neurulation
a portion of the mesoderm forms a tubelike structure called the notocord.
neural plate
forms above the notocord from thickened ectoderm
neural tube
formed from invagination of the neural plate. a precursor to the brain, spinal cord, and components of the eye.
morphogenesis
"genesis of form". part of gastrulation
induction
development of one region of tissue is influenced by the tissues that surround it.
differentiation
the process by which a cell becomes more specialized
determination
the process whereby the number of possible tissue types a cell could become is progressively limited
endoderm gives rise to...
inner lining of esophagus, stomach, and intestines.

also organs that are outgrowths of the digestive system, such as pancreas, gall bladder, and liver.

also inner lining of the respiratory tract.
ectoderm gives rise to...
epidermis, eye, and nervous system
mesoderm gives rise to...
connective tissue, heart, blood cells, and urogenital system.
bacilli
rod-shaped bacteria
cocci
round-shaped bacteria
spirilla
spiral-shaped bacteria
binary fission
the asexual reproduction of a bacterium
transformation
involves the addition and incorporation of genetic material into a bacterium's genome from its surroundings.
conjugation
a plasmid transfers DNA from one bacterium to another. bacterial "mating"
F (fertility) factor
a bacterial plasmid which facilitates the transfer of DNA from one bacterium to another.
transduction
a virus transfers DNA from one bacterium to another.
the proteinaceous outer coat of a virus
capsid
the nucleic acids contained w/in the coat
core
bacteriophage
a type of virus that infects bacteria using a tail fiber
tail fiber
used by bacteriophages to facilitate infection by allowing the virus to attach itself to the bacterial host, and to inject its genome into the host.
receptors
found on the host's cell membrane. facilitate the attachment of viral protein coat molecules.
lytic virus
appropriates the cell's reproductive machinery to make copies of its own nucleic acids and proteins, which then combine to form new viruses.
lysogenic virus
incorporates its nucleic acid into the host's genome
prophage
a lysogenic virus that infects bacteria
provirus
a lysogenic virus that infects eukaryotic cells
fungi
primarily haploid organisms whose cells are eukaryotic
fungal cell walls are composed largely of __________
chitin
unicellular fungi
yeasts
multicellular fungi
molds, mushrooms, and mildews
the principle distinguishing feature of many multicellular fungi
the absence of a partition btwn what would otherwise be separate cells. somewhat multinucleate.
asexual fungal reproduction occurs through... (3 things)
budding, fission, or spore formation
budding
a cell separates from the parent organism, grows, and becomes a new organism itself.
fission
a single fungal cell divides to produce two new daughter cells.
sporulation
fungus produces spores and release them from hyphae.

allows undeveloped organism to survive hostile environmental conditions
hyphae
stem-like structures from which fungi produce and release spores.

produce gametes.
autotrophs
capture their own energy through photosynthesis or through chemical means
heterotrophs
rely on other organisms for nutrition
parasites
obtain nutrition directly from the body of a living organism to the detriment of that organism.
saprophytes
absorb nutrients from the remains of dead organisms
obligate anaerobes
unable to live in the presence of oxygen
faculative anaerobes
use oxygen in their respiratory process if it is available, but will conduct anaerobic respiration in its absence.
tolerant anaerobes
always conduct anaerobic respiration but are indifferent to the presence of oxygen.
mutualism
a relationship btwn two organisms in which each confers a benefit on the other.
active site
the site at which an enzyme associates w/ its substrate.
lock-and-key hypothesis
states that an enzyme's shape accommodates precisely the shape of the substrate.
induced fit hypothesis
states that the enzyme's shape compels the substrate to take on the shape of the reaction's transition state.
denaturation
the breakdown of an enzyme's shape.

occurs under conditions that disrupt the hydrogen bonds functioning to maintain secondary and tertiary structure.
cofactors
inorganic substances (ex. Fe and Cu ions) that certain enzymes require for their activity
coenzymes
organic substances, such as vitamins, that certain enzymes require for their activity
competitive inhibition
substrate and inhibitor compete for an enzyme's active site
glycolysis produces net gain of...
2 ATP, 2 NADH
fermentation
the anaerobic process in which pyruvate is reduced by NADH to produce lactate, regenerating NAD+
fermentation produces net gain of...
2 NAD+, 2 lactate
oxidative decarboxylation
occurs after glycolysis in preparation of Kreb cycle.

acetyl group that is produced is combined w/ coenzyme A to produce acetyl CoA
Kreb / citric acid cycle
pyruvate + CoA + NAD+ --> acetyl CoA + CO2 + NADH

acetyl CoA + oxaloacetate --> citrate

citrate undergoes series of redox rxns that lead to removal of 2 carbons as CO2. Energy released is used to produce 3 NADH and 1 FADH2
products of one turn of Kreb's cycle:
3 NADH
1 FADH2
1 GTP
2 CO2
respiration is controlled by the _______
medulla oblongata
part of the medulla oblongata in which signals that initiate each cycle of breathing arise
respiratory center
the major muscle of respiration
diaphragm
carries signals from the medulla oblongata to the diaphragm, stimulating the diaphragm to contract
phrenic nerve
the _________ of the lung causes it to resist expansion
elasticity
nose and mouth
serve to warm and moisten air as it enters the body
nares
nostrils. mucus and hair lining serves to trap large particles in the air
trachea
a mucous-membrane lined tubular structure whose lumen (airway) is kept open by cartilaginous rings embedded in the wall.
macrophages
phagocytize small particles that reach the alveoli
surfactant
relieves surface tension. has a polar and a nonpolar end. keeps alveoli from collapsing.
the respiratory center is most sensitive to:
carbon dioxide concentration
myocardium
the muscular tissue of the heart
leaflets / cusps
make up heart valves. Open when pressure is applied in the forward direction and close when pressure is applied in the backward direction.
native position
closed (heart valve)
tricuspid valves
tricuspid, pulmonic, and aortic valves
diastole
the atria are first relaxed and then contracted.
systole
the two ventricles contract
vagus nerve
slows the rate of the sinus node to decrease heart rate
purkinje fibers
spreads the electrical signal throughout the ventricular walls
platelets
cell fragments of a megakaryocyte that function in clotting
all blood cells arise from precursor cells w/in the ___________
bone marrow
hematocrit
the percentage of whole blood volume occupied by red cells
plasma
blood stripped of its cells
serum
plasma w/out fibrin
oncotic pressure
a specific form of osmotic pressure across capillary walls due to the presence of proteins in the blood.

functions to push fluids into the capillary.
hydrostatic pressure
pushes fluid out of the capillary
lymph enters ultimately into the __________ ...
thoracic duct, which enters ultimately into the venous system at the junction of the left internal jugular and subclavian veins
spleen
acts as a lymphatic filter for blood.

destroys senescent (aged) erythrocytes
thymus
the place of maturation of T-lymphocytes. becomes nonfuctional in adulthood.
T-cells
cell-mediated immunity
digestive enzyme in saliva that initiates the digestion of starch:
salivary amylase
peristalsis
a highly coordinated series of contractions which allow for transit of a bolus
parietal cells
secrete hydrochloric acid into the stomach
stimulates the production and secretion of HCl:
vagus nerve
chief cells
secrete pepsin into the stomach
pepsin
initiates the chemical breakdown of proteins. requires low pH.
pyloric sphincter
separates stomach from the large intestine.
duodenum
the first section of the small intestine
chyme
liquid food mixture once it is in the intestine
pancreas
synthesizes enzymes that are delivered into the duodenum via the pancreatic duct
zymogens
an inactive form of pancreatic enzymes. cleaved by an enzyme to be activated.
trypsin
an active protein-degrading enzyme
pancreatic amylase
chemically identical to salivary amylase. continues the digestion of carbohydrates.
bile
produced in the liver and stored in the gall bladder.

acts as an emulsifier.
emulsifier
separates large globules of fat molecules into smaller globules
bile enters the duodenum from the gall bladder via the ...
common bile duct
glycogen
the storage form of glucose
functions of the liver
1) bile production
2) carbohydrate metabolism (converting glucose to glycogen)
3) converting amino acids into keto acids and urea
4) processing toxins
5) degradation of aged erythrocytes
ileocecal valve
separates the small and large intestines
the most important function of the large intestine is ...
the resorption of large amounts of water
inorganic constituents of bone matrix
calcium and phosphate
a crystalline compound formed from calcium and phosphorous in the bone
hydroxyapatite
organic components of bone matrix
Type I collagen and ground substance
ground substance consists largely of... (2 things)
glycosaminoglycans and proteins
______ and _______ create the characteristic hardness and resistance of bone
hydroxyapatite and collagen
osteoblasts
located on inner surfaces of bone tissue. synthesize Type I collagen and other organic components of the matrix.
osteocytes
occupy lacunae w/in the bony matrix. osteoblasts w/ greatly reduced synthetic capacity. responsible for maintaining the matrix.
lacunae
minute spaces w/in the bony matrix
osteoclasts / multinucleated giant cell
promote ongoing breakdown, resorption, and remodeling of bone
collagen
imparts flexibility to bone
compact bone
the outer, dense portion of bone
spongy bone
the inner spongy-looking area of bone w/ small, marrow-filled cavities.
red bone marrow
the site of red blood cell and platelet production and some immune cell development and maturation.

confined to flat bones in healthy adults.
yellow bone marrow
filled w/ adipocytes (fat cells)
lamellae
rings running parallel to the bone's long axis that make up a Haversian system, or osteon
Haversian system / osteon
distribute nutrients throughout compact bone. give compact bone its strengh.

each is a set of concentric lamellae
Haversian canal
at the center of each Haversian system.

carries blood vessels and nerves, and is filled w/ loose connective tissue.
spicules
thin segments of bone in spongy bone that surround the many small marrow spaces.

absorb nutrients directly from the marrow, so do not need Haversian systems.
fibrous joints
composed of collagen fibers and are designed to allow minimal movement
synovial joints
allow for a great range and extent of movement
synovial capsule
made of fibrous tissue covering the ends of two bones. contains synovial fluid
articular cartilage
covers the ends of bones in a synovial joint.
ligaments
attach bone to bone
tendons
attach muscles to bones
myofibers
skeletal muscle cells
fascicle
a group or bundle of myofibers
sarcomere
a segment of muscle fiber btwn two Z lines
thin filament
anchored at one end to a Z line.

composed of actin.
thick filament
have no connection to the Z lines.

composed of myosin.
contraction of muscle is achieved by...
the sliding of actin and myosin filaments over each other, bringing the Z lines closer together
A band
the length of a myosin (thick) filament
I band
the length of thin filament that does not overlap w/ any thick filament
H zone
the middle of the sarcomere, containing only myosin filaments w/ no overlapping actin filaments
crossbridges
extend from the myosin filament to the actin filament. allow contraction to occur by a sliding filament mechanism
ratio moved by Na-K ATPase
2 potassium in, 3 sodium out
relative ion concentrations inside and outside cell
Na+ concentration higher outside than inside

K+ concentration higher inside than outside
net relative charge across membrane
cell's interior electrically negative relative to its exterior
membrane resting potential
refers to the existence of a charge gradient across the cell membrane and to the fact that the inside is negative to the outside
depolarized
when the charge gradient has reversed itself so that the interior is positive relative to the exterior.

occurs due to the flow of Na into the cell
threshold potential
the membrane potential that must be reached for depolarization to occur
repolarized
occurs due to the flow of K into the cell
action potential
designates rapid depolarization followed by repolarization
tropomyosin
covers the site on the actin w/ which myosin heads interact
troponin
binds calcium ions, causing tropomyosin to uncover the actin sites to which myosin attaches
sarcolemma
the cell membrane of a myofiber
sarcoplasm
the cytoplasm of a myofiber
sarcoplasmic reticulum
the endoplasmic reticulum of the myofiber, which stores calcium ions
acetylcholine
a neurotransmitter that is released from a motor neuron when it experiences depolarization
T-tubules
a series of invaginations in the sarcolemma which carry action potentials deep into the myofiber
phosphocreatinine
stored in myofibers. embodies a high-energy phosphate bond. dephosphorylation releases energy, which is used to regenerate ATP from ADP
cardiac muscle
operates involuntarily. structure similar to skeletal muscle's; striated.

have gap junctions.
intercalated disks
dark lines which represent gap junctions
gap junctions
attachment points btwn adjacent muscle cells which allow flow of ions from one fiber to the next, so that action potential is easily propagated.
syncytium
a multinucleate mass of cytoplasm resulting from fusion of cells. describes the myocardium.
smooth muscle
under involuntary control.

cells are mononucleate, elongated, and nonstriated. absence of striations due to irregularity of arrangement of actin and myosin filaments.

no troponin or tropomyosin, contraction induced differently than in skeletal muscle.

have gap junctions
in smooth muscle cells, calcium ions bind to a calcium-binding protein called __________
calmodulin
calcium-calmodulin complex interacts w/ a protein called _________
myosin light chain kinase
myosin light chain kinase
directly phosphorylates the myosin head, allowing myosin to form a cross-bridge w/ actin
kidneys play four important roles in maintaining homeostasis:
1) excretion of hydrophilic waste
2) maintain constant solute concentration
3) maintain constant pH
4) maintain constant fluid volume
renal cortex
the outer portion of the kidney.
renal medulla
the inner portion of the kidney. composed or renal pyramids.
renal pyramids
wedge-shaped tissue structures composing the renal medulla
renal pelvis
makes up the innermost portion of the kidney, around which the medulla and cortex are wrapped.

an extension and expansion of the ureter.
ureter
connects the kidney to the urinary bladder.
nephron
the basic structural and functional unit of the kidney
renal corpuscle
the part of the kidney nephron in which blood plasma is filtered.

comprised of glomerulus, a glomerular basement membrane, and a Bowman's capsule.
renal tubule
a hollow tube surrounded by epithelium cells.
glomerulus
a tuft of capillaries in the renal corpuscle
Bowman's capsule
a double-walled cup formed as an enlargement of the proximal end of the renal tubule.

functions in blood filtration
course of renal tubule
Bowmans capsule, proximal convoluted tubule, descending loop of Henle, ascending loop of Henle, distal convoluted tubule, collecting duct
located in the renal cortex are:
renal corpuscle, proximal convoluted tubule
location of the loop of Henle
dips into the pyramids of the renal medulla and courses back into the cortex
location of the collecting duct
courses back down into the medullary pyramids
papillary duct
formed from the merging of many nearby collecting ducts.

empty into the calyces of the renal pelvis
calyces
funnel-shaped sections of the renal pelvis
micturition
urination
renal artery
delivers the blood to be filtered to the kidney. branches off the abdominal aorta.
afferent arterioles
branch off the renal artery. travel to individual renal corpuscles.
glomerular capillaries
branch off the afferent arterioles. inside the Bowman's capsule.
visceral layer
the inner wall of the Bowman's capsule. porous and permeable to plasma and other small blood constituents.
parietal layer
the exterior wall of the Bowman's capsule. neither porous nor permeable.
Bowman's space
the space enclosed by the parietal and visceral layers. the origin of the renal tubule.
filtrate
composed of components that pass from the glomerulus across the basement membrane, through the porous viceral layer of Bowman's capsule and into Bowman's space.

will eventually become urine.
allows for high blood pressure in the capillaries of the glomerulus (2 things)
efferent arterioles are narrower than afferent ones

efferent arterioles can constrict
result of relatively high pressure in the capillaries of the glomerulus
fluid travels from the capillaries into the Bowman's capsule
efferent arterioles
where the filtered blood leaves the glomerulus. eventually fuses w/ the renal vein.
most reabsorption in the kidney occurs at the __________
proximal convoluted tubule
secretion
the process by which waste molecules are added to the filtrate
the salt concentration of the cortical interstitial fluid is ______ relative to that of the medullary interstitial fluid
low
descending loop of Henle is permeable / impermeable to...
permeable to water, impermeable to solutes
ascending loop of Henle is permeable / impermeable to...
impermeable to water, permeable to sodium
vasa recta
blood vessels continuous w/ the renal vein which reabsorb water that flows into the interstitium of the renal medulla
permeability of collecting tubule
permeable to water (regulated), impermeable to salt
regulates collecting tubule's permeability to water
antidiuretic hormone (ADH) or vasopressin
vasopressin
regulates the permeability of the collecting tubule to water.

synthesized in the hypothalamus and secreted by the posterior pituitary
ADH
antidiuretic hormone.

dehydration causes its release. it increase the collecting duct's permeability to water.

stored in the posterior pituitary
endocrine system
controls body homeostasis by promoting communication among various tissues and organs through the secretion of hormones
hormones
secreted by endocrine glands

act slowly and for long periods to maintain homeostasis

come in contact w/ almost every cell in body, but affects only cells that have receptors that bind them
hormones are released from the endocrine gland into ______
the bloodstream
exocrine gland
secrete their products into the external environment via ducts

Ex. salivary glands, mammary glands, pancreatic acinar cells, sweat glands
target cells
those cells that have receptors for, and therefore are affected by, a specific hormone
pancreas
both endocrine (secretes from acinar cells into duodenum) and exocrine gland
hormones that pancreas secretes (3 things)
insulin, glucagon, somatostatin
endocrine secretions of the pancreas come from __________
islet cells
islet cells are located in the ______
islets of Langerhans
insulin
secreted by beta cells

regulates glucose transport, storage, and metabolism
glucagon
secreted by alpha cells

regulates glucose transport, storage, and metabolism
somatostatin
secreted by gama cells.

inhibits digestive processes.
glucose in our body comes from... (2 things)
polysaccharides that we eat are chemically broken down and then absorbed by the gastrointestinal tract.

glucose is produced by the live and released into the blood
in the absence of insulin...
all body cells except those of the brain and liver are impermeable to glucose.

glucose in the blood remains in the blood.
when insulin secretion is high...
circulating glucose is taken up by cells throughout the body, lowering blood glucose levels.
when the liver takes up glucose, it converts it to _________
glycogen
main functions of insulin in the body (4 things)
1) increasing cellular uptake of glucose
2) promoting formation of glycogen from glucose in the liver
3) reducing glucose concentration in the blood
4) increasing protein and triglyceride synthesis
glucagon
has effects opposite to those of insulin. increases blood sugar concentration. increases breakdown of lipids

promotes the breakdown of glycogen in the liver (glycogenolysis)

also promotes the manufacture of glucose in the liver (gluconeogenesis)

does NOT decrease cellular uptake of glucose
glycogenolysis
the process by which glycogen is broken down in the liver
gluconeogenesis
the process by which glucose is synthesized in the liver from lactate, amino acids, and triglycerides.
hyperglycemia
excessively high levels of glucose in the blood. typically due to diminished insulin secretion or activity.
hypoglycemia
excessively low levels of glucose in the blood. results from elevated levels of insulin or insufficient glucagon levels.
adrenal gland is composed of... (2 things)
adrenal cortex and adrenal medulla
adrenal cortex
the outer portion of the adrenal gland. produces a class of endocrine hormones called corticosteroids
subdivisions of corticosteroids (3 things)
mineralocorticoids, glucocorticoids, sex hormones
mineralocorticoids
affect levels of the minerals sodium and potassium in the body
the main mineralocorticoid secreted by the adrenal cortex is _______
aldosterone
aldosterone
acts at the distal convoluted tubule of the kidney to promote sodium-potassium exchange. increases activity of sodium potassium pumps.

tends to promote the movement of water from tubule to interstitium
ultimate effects of aldosterone (3 things)
1) increased urinary excretion of potassium
2) increased interstitial sodium concentration
3) increased water concentration
aldosterone secretion is stimulated by... (3 things)
high levels of extracellular potassium, low levels of extracellular sodium, and low fluid levels (blood volume)
glucocorticoids
affect plasma glucose concentrations.

increase blood glucose levels, strengthens cardiac muscle contractions, increases water retention, and have anti-inflammatory and anti-allergic activities.
the main glucocorticoid secreted by the adrenal cortex is _________
cortisol
cortisol
released as part of long-term stress response and affects most tissues in the body.

increases plasma glucose levels (via increasing gluconeogenesis) and inhibits immune activity.
cortisol release is controlled by... (2 things)
the hypothalamus and the anterior pituitary
the adrenal cortex secretes low levels of the sex steroids, mostly ______
the androgens (sex hormones which are dominant in men)
the adrenal medulla secretes ________, mostly _________
catecholamines, mostly epinephrine / adrenaline
epinephrine
an amino acid derivative that acts like a peptide hormone. reserved for stressful situations in which the body prepares for the "fight or flight" response.

increases heart rate, raises blood pressure, and increases alertness.
thyroid
a flat gland located in the neck, in front of the larynx.

synthesizes calcitonin and the thyroid hormones
thyroid hormones include... (2 things)
thyroxine (T4) or its analog, triiodothyronine (T3)
the thyroid hormones are synthesized in the _________ from __________
in the follicles of the thyroid gland from the amino acid tyrosine
polarity of thyroid hormones
hydrophobic, travel in the plasma bound to plasma proteins.

lipophilic, not hydrophilic
the release of thyroid hormones is controlled by the (2 things)
the hypothalamus and the anterior pituitary
structural difference btwn thyroxine and triiodothyronine
thyroxine contains 4 atoms of iodine,
triiodothyronine contains 3 atoms of iodine
effect of thyroid hormones
produce a generalized increase in metabolism

stimulate increased oxygen demand, heat production, growth and development
hypothyroidism
refers to an inadequate production of thyroid hormone

patients tend to be overweight and slowed down in physical activities
goiter
excessive growth (hypertrophy) of the thyroid due to insufficient dietary iodine.
calcitonin
a peptide hormone that reduces blood calcium concentration and inhibits the normal process of bone resorption
calcitonin is produced in __________
the parafollicular cells of the thyroid
parathyroids
four small glands on the posterior aspect of the thyroid gland

secrete parathyroid hormone
parathyroid hormone (PTH)
exerts effects opposite to those of calcitonin.

secreted in response to low blood levels of calcium. increases levels of blood calcium.
effects of parathyroid hormone (3 things)
1) increases bone resorption and calcium release
2) increases intestinal calcium uptake
3) promotes calcium re-uptake at the kidney
the ovaries are responsible for the synthesis of ______ and ______
estrogen and progesterone
follicular phase
the first phase of the ovarian cycle.

anterior pituitary gland secretes two hormones that stimulate the growth of one follicle containing several ova, only one of which fully matures
the two follicular hormones are _______ and _______
follicle-stimulating hormone (FSH) and luteinizing hormone (LH)
the follicular hormones are secreted by the ___________
anterior pituitary gland
the ovarian follicle releases the hormone ______ as it develops
estrogen
what prevents maturation of more than one follicle at a time during the follicular phase?
increased ovarian estrogen release
at the end of the follicular phase...causing...
there is a surge in LH secretion from the anterior pituitary, causing the release of the ovum from the follicle, where it is swept into the fallopian tube
the ovum is swept into the fallopian tube by _______
the fimbrae
ovulation
the release of the ovum from the follicle
luteal phase
the final stage of the ovarian cycle. the corpus luteum secretes estrogen and progesterone
corpus luteum
the part of the ruptured follicle that remains in the ovary.
menses
the first phase of the uterine cycle. shedding of the uterine lining.

occurs at the same time as the early follicular phase in the ovary.
proliferative phase
estrogen from the ovaries induces the proliferation of the endometrium.
secretory phase
the final phase of the uterine cycle.

progesterone from the corpus luteum promotes the rapid thickening and vascularization of the uterine lining in preparation for the implantation of the fertilized ovum.
if the ovum is fertilized, the developing placenta begins to secrete ___________
human chorionic gonadotropin (hCG)
human chorionic gonadotropin (hCG)
prevents the corpus luteum from degenerating, allowing it to continue secreting progesterone --> maintenance of uterine lining.
the placenta begins to secrete ________ and _______
estrogen and progesterone
seminiferous tubules
located in the testes. contain spermatogonia.
spermatogonia
the precursors of spermatozoa formation.
testosterone is secreted by...
the interstitial cells situated among the seminiferous tubules. secreted under the stimulus of pituitary LH (also called ICSH)
pituitary LH is also called ________ in males
interstitial cell stimulating hormone (ICSH)
functions of testosterone (2 things)
promotes spermatogenesis in the testes

promotes the development of secondary sex characteristics
hypothalamus
a portion of the diencephalon of the forebrain.

integrates info from cerebral cortex and limbic systems --> releases hormones that control secretions from the pituitary gland.

the "control center" of the endocrine system and autonomic nervous system.
anterior pituitary secretes: (6 things)
1) thyroid stimulating hormone (TSH)
2) adrenocorticotropic hormone (ACTH)
3) luteinizing hormone (LH)
4) follicle stimulating hormone (FSH)
5) growth hormone (GH)
6) prolactin
tropic hormones (4 things)
act as chemical switches, stimulating or inhibiting other endocrine glands

1) thyroid-stimulating hormone (TSH)
2) adrenocorticotropic hormone (ACTH)
3) luteinizing hormone (LH)
4) follicle stimulating hormone (FSH)
adrenocorticotropic hormone (ACTH)
stimulates the adrenal cortex to secrete cortisol
luteinizing hormone (LH) and follicle stimulating hormone (FSH)
stimulates the gonads to promote sex hormone secretion and gamete production
growth hormone (GH) / somatotropin (STH)
influences the development of skeletal muscle, bone, and organs in children
prolactin
targets the female breasts, where it stimulates breast development and milk production
posterior pituitary stores _________ and ___________
secretes antidiuretic hormone (ADH) / vasopressin and oxytocin
ADH and oxytocin are synthesized in _________ and transported __________ to __________
made in neural soma in the hypothalamus and transported via vesicles down axons to the posterior pituitary.
oxytocin
released at childbirth, causing the uterus to contract
mechanisms of hormone release (3 things)
1) regulation by instructions from the brain (hypothalamus and pituitary gland)
2) hormones can regulate other hormones
3) hormone levels controlled by feedback regulation
tropic hormones
hormones that control the release of other hormones
tropic hormone cascade of gamete production and secondary sex characteristics
GnRH in hypothalamus --> LH and FSH in anterior pituitary--> sex steroids in ovaries/testes --> gamete production and secondary sex characteristics
tropic hormone cascade of metabolism, growth, and development
TRH in hypothalamus --> TSH in anterior pituitary --> T3 and T4 in thyroid --> metabolism, growth, and development
tropic hormone cascade of inc. blood glucose, inc. protein catabolism, dec. inflammation
CRH in hypothalamus --> ACTH in anterior pituitary --> cortisol in adrenal cortex --> increased blood glucose, increased protein catabolism, decreased inflammation
major divisions of feedback regulation (2 things)
1) change in physiological status in response to hormone can feed back to endocrine gland to stop hormone secretion

2) hormones can cause feedback to the higher regulatory organs (hypothalamus and pituitary gland) that are causing their release
synaptic terminals
extensions on the distal end of the axon. contain synaptic vesicles, which store neurotransmitters.
resting potential
-70 millivolts. the charge of the neuronal interior relative to the exterior.
potassium leak channels
causes the neuron's membrane to be somewhat permeable to potassium at rest
threshold
-50 mV. the internal charge that must be reached for voltage gated sodium channels to be opened.
inactivated sodium channel
occurs when cell has depolarized to +35 mV. do not allow sodium into cells but are unable to open. channel must be reset to the closed conformation b/f it can open again, which occurs during absolute refractory period.
repolarization
when the cell's interior becomes negative once again due to the influx of potassium
hyperpolarization
when the potential drops to -90 mV due to delay in closure of the voltage-gated potassium channels
action potential
1) depolarization (-70 mV to +35 mV) due to sodium inflow

2) repolarization (+35 mV to -70 mV) due to potassium outflow
absolute refractory period
interval during which a second action potential absolutely be initiated. occurs during depolarization and repolarization to -70 mV.
relative refractory period
interval after cell passes -70 mV and is hyperpolarized. cell is susceptible to another action potential but requires a stimulus stronger than the one normally needed. occurs b/c the potential of the cell is below that of a resting cell.
myelination
schwann cells encase axons of the peripheral nervous system by wrapping layers of their plasma membranes around the axons, creating myelin sheaths
oligodendrocytes
have a similar function as Schwann cells in the central nervous system
nodes of Ranvier
unsheathed areas of the axon that are the only sites available for electrical propagation along the axon.
saltatory conduction
depolarization jumps from one node of Ranvier to the next. accelerates transmission of the impulse.
when the action potential impulse arrives at the end of the axon, it triggers ___________ to open
voltage-gated calcium channels
once voltage-gated calcium channels open,...
Ca2+ flows into the cell, binds w/ regulatory protein and causes exocytosis of neurotransmitter-containing synaptic vesicles
presynaptic neuron
the neuron that releases the neurotransmitter
synaptic cleft
the space btwn the presynaptic membrane and the postsynaptic membrane into which neurotransmitters are released
ligand-gated ion channels
what most postsynaptic receptors are, w/ specific neurotransmitters serving as ligands. binding of neurotransmitter induces conformational change in receptors that open ion channels w/in the membrane
acetylcholine
triggers skeletal muscle contraction.

degraded by the enzyme acetylcolinesterase
epinephrine / adrenaline
increases heart rate and blood pressure. decreases metabolic activity.

oxidized by monoamine oxidase (MAO) and methylated by catechol-O-methyl transferase (COMT) to inactive metabolites
sensory / afferent neurons
receive info from sensory receptors and send it to central nervous system.
interneurons / associative neurons
receive and process information in the CNS. function in relaying signals from neuron to neuron.
motor / effector / efferent neurons
convey signals from the CNS to the target muscle, organ, or gland.
meninges
layers of connective tissue that protect the CNS
cerebrospinal fluid (CSF)
acts as a liquid shock absorber to protect the CNS
hindbrain becomes... (3 things)
the cerebellum, pons, and medulla
midbrain becomes...
structures that govern visual and auditory reflexes and coordinate information on posture and muscle tone.
forebrain becomes... (2 things)
diencephalon and telencephalon
diencephalon includes...
thalamus, hypothalamus, and pituitary gland
telencephalon includes...
cerebrum, lymbic system, and basal nuclei
cerebrum divided by __________
a longitudinal fissure
two hemispheres of the cerebrum are connected by a thick bundle of axons called the __________
corpus collosum
cerebral cortex
made up of grey matter. conducts the highest of intellectual functions. integrates and interprets sensory signals. governs voluntary motor activity.

divided into frontal, parietal, temporal, and occipital lobes
hypothalamus
maintains homeostasis through hormonal regulation
thalamus
relays information btwn spinal cord and cerebral cortex
pons
connects the spinal cord and medulla w/ upper regions of the brain
grey matter
composed of unmyelinated neuronal cell bodies
white matter
composed of myelinated axons
simple reflex arc
stretch receptors register stretch of muscle fibers due to tap on tendon. sensory neuron synapses w/ dendrites of a motor neuron, which sends impulse to muscle fiber bundle.
stretch receptor
specialized endings of affector neurons which are wrapped around individual muscles fibers and register tap-induced fiber stretch.
somatic nervous system
governs voluntary activities that we can consciously control.

afferent neurons receive info from sensory receptors for pain, touch, temperature, and proprioception.

efferent neurons innervate skeletal muscles by releasing acetylcholine
autonomic nervous system
controls involuntary actions.
subdivisions of the autonomic nervous system (2 things)
parasympathetic and sympathetic nervous systems
preganglionic neuron
efferent neuron of the autonomic nervous system. has its cell body in the brainstem or the spinal cord. synapses w/ the postganglionic neuron and releases acetylcholine.
postganglionic neuron
can release acetylcholine or norepinephrine to control the effector tissue.
ganglion
a cluster of nerve cell bodies in the PNS.
sympathetic nervous system
prepares body for fight-or-flight response. increases heart rate and blood pressure, and temporarily inhibits vegetative functions.
parasympathetic nervous system
"rest and digest". decreases heart rate and increases digestive activity.
vagus nerve
part of parasympathetic nervous system. innervates thoracic and abdominal regions. slows down heart rate at SA node.
rods
more sensitive to dim light. responsible for night vision.
cones
require abundant light. responsible for color and high-acuity vision.
nocireceptors
pain receptors.
2 functions of ear...
1) maintenance of postural equilibrium

2) reception of sound
the inner ear is the location of __________
the vestibular apparatus
vestibular apparatus
interprets positional information required for maintaining equilibrium

consists of membranous labyrinth situated w/in 3 semicircular canals
semicircular canals
oriented perpendicularly to one another in the vestibular apparatus
movement of the head causes...
movement of fluid w/in the labyrinths and displacement of crista
crista
specialized hair cells located in the ampulla at the base of the semicircular canals
vestibular nerve
conveys sensory impulses initiated by movement of crista to centers in the cerebellum, midbrain, and cerebrum
directional movement and position are interpreted in the.. (3 things)
cerebellum, midbrain, and cerebrum
external ear is composed of the ______
pinna
pinna
funnels sound waves into the ear canal
tympanic membrane
located in middle ear. vibrates in response to sound waves.
vibration of the tympanic membrane sets into motion...
the three auditory bones, the malleus, incus, and stapes
movement of the stapes is transmitted across the __________ into the ________
oval window into the inner ear
transmission across the oval window into the inner ear sets up...
vibrations of the fluid of the cochlea
vibrations in the fluid of the cochlea causes...
bending of auditory hair cells in the organ of Corti
the 2 branches of the acoustic nerve are formed by...
the cochlear nerve and the vestibular nerve
light enters the _______, transverses the _____, passes through the _______, and proceeds through the _____ and _________ until it reaches the light receptors of the _________
cornea, aqueous humor, pupil, lens and vitreous humor, retina
one light reaches the retina, electrical signals are transmitted via the _________ to the brain
optic nerve
the lens
a transparent structure that focuses light rays on the retina
myopia
nearsightedness. occurs when the lens focuses light from a distant object in front of the retina
hyperopia
farsightedness. occurs when light from a nearby object is focused behind the retina.
the pigment that mediates rod reception is _________
rhodopsin
light reception in cones is mediated by ____________
opsin
the iris
the colored part of the eye. contains muscles that dilate and constrict to regulate the amount of light that reaches the retina
ciliary muscle
changes the shape of the lens as the eye shifts its focus from distant to nearby objects
functions of the skin (3 things)
1) maintains body temperature
2) registers info from the environment
3) provides a barrier against infection
three layers of the skin:
epidermis, dermis, and subcutaneous tissue
epidermis
composed of stratified squamous epithelium and has a layered, flat cell structure.
stratum corneum
the external layer of the epidermis, composed of many layers of dead cells.

waterproof, and provides resistance to invasion of the body by microorganisms
the dead cells of the stratum corneum contain the protein _________
keratin
stratum germinativum
below the stratum corneum. where skin cells replicate through mitosis and where keratin is produced. migrate upward, loosing contact w/ capillaries, and dying to form layers of the corneum
dermis
directly underlies the stratum germinativum of the epidermis, and contains the blood vessels, nerve endings, sebaceous glands, and sweat glands.
subcutaneous tissue / hypodermis contains primarily__________
adipose tissue (fat)
in most eukaryotic organisms, most genes code for ___________
peptides
introns
non-protein coding DNA sequences found in eukaryotes
three gene products:
rRNA, tRNA, polypeptide
genetic locus
the area on a chromosome on which a gene is physically located.

a gene's address on the chromosome and in the genome.
at any given genetic locus, the two chromosomes of a given homologous gene pair might be: (2 options)
a) identical in DNA sequence and code for the same form of the gene

b) different in DNA sequence and code for different versions of the same gene
alleles
different forms or versions of a gene
homozygous
having the same allele on both homologous chromosomes
heterozygous
having two different alleles
genotype
the full complement of alleles possessed by an organism
law of segregation
allele pair separate during gamete formation, and randomly unite at fertilization
law of independent assortment
allele pairs separate independently during gamete formation
phenotype
an organism's traits
genotype
an organism's overall inventory of alleles
homozygous
two alleles for a given locus, or gene, are identical
heterozygous
two alleles on corresponding sites of homologous chromosomes are different
testcross
one of the mated individuals is homozygous recessive.
incomplete dominance
producing an intermediate phenotype or a blended phenotype
co-dominance
two different alleles for the same locus express themselves as two distinct phenotypes both present in a single individual.

Ex. blood groups (possible to have AB)
I^A allele
codes for an enzyme that adds the sugar galactosamine to the lipids on the surface of red blood cells
I^B allele
codes for an enzyme that adds the sugar galactose to the lipids on the surface of red blood cells
genetic recombination
genetic information on one chromosome is moved to:

1) a chromosome that belongs to some other cell, or

2) a different chromosome w/in the same cell
point mutation
when one nucleotide unit is substituted for another
frameshift mutation
occurs when one or more nucleotides are added or deleted
silent mutation
does not change the amino acid that is added during translation, and therefore does not affect gene function
missense mutation
changes the amino acid that is added, and therefore affects gene function
nonsense mutation
if the mutation causes the conversion of an mRNA codon to a stop codon
autosomes
the 22 pairs of homologous chromosomes
autosomal traits
affect males and females w/ equal frequency
mitochondrial traits
passed onto offspring from the mother. either present or absent, recessive/dominant doesn't apply.
y-linked traits
passed from father to son, never affect females. either present or absent, recessive/dominant doesn't apply.
x-linked / sex traits
carried on the X chromosome. can be dominant or recessive.

Ex. color blindness and hemophilia
pedigrees
diagrams that show the genetic information of a family tree.

squares are male, circles are female, diamonds are unknown sex.
gene pool
constitutes the total possible assortment of genes found in the population of a species.
mutation
the spontaneous addition, transfer, rearrangement, or deletion of one or several nucleotides in a section of DNA.
evolution
a change in the genetic makeup of a population.
fitness (in respect to evolution)
the ability of an organism's genotype to persevere in subsequent generations.
speciation
the evolution of a new species from a preexisting species
divergent evolution
when species evolving from the same group maintain a similar structure from the common ancestor.
reproductive isolation
insularity of a gene pool from genetic mixing. occurs when two species capable of interbreeding are prevented from doing so.
adaptive radiation
when a population experiences change in genotype that render it reproductively isolated from other populations of its parent species --> new species
adaptive radiation is associated w/... (2 things)
reduced competition and an alteration of the organism's original niche
niche
the organism's "environment", the role it plays
allopatric speciation
a form of adaptive radiation. arises through geographic separation.
sympatric speciation
a form of adaptive radiation. two closely related populations of one species diverges, such that their differences allow them to exploit different niches w/in the same environment.
Hardy-Weinberg law
the occurrence of dominant and recessive alleles w/in a population remains constant over time.
frequency
the fractional contribution an allele makes to the total population of both alleles
p
the frequency of the dominant allele
q
the frequency of the recessive allele
equations of the Hardy-Weinberg law
p+q=1

p^2 + pq + q^2 = 1
genetic drift
the pattern of allele frequency alteration that occurs in small populations. arises by chance.
taxonomy
the classification of organisms
the order of classification from most comprehensive to most specific:
kingdom, phylum, class, order, family, genus, species
chordates
a phylum identifiable by the presence of a dorsal nerve cord, gill slits, and a notocord.
vertibrates
chordates recognized by possession of a vertebral column, a closed circulatory system, a developed nervous system, and a developed sensory apparatus
symbiosis
a prolonged, intimate association btwn a member of one species and a member of another species
mutualism
each partner derives benefit from the association
commensalism
one partner benefits, other partner neither benefits nor is harmed
ecosystem
a self-sustaining natural system, composed of both living and nonliving components