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417 Cards in this Set

  • Front
  • Back
each amino acid in a polypeptide chain is referred to as a ______
the major component of extracellular matrix
carry out electron transport in the ETC

proteins which require a prostetic heme group to function
conjugated proteins
proteins containing nonproteinaceous components
storage form of glucose, synthesized by liver. mostly found in muscle and liver cells.

Except for digestive tract and kidney, all cells absorb glucose via facilitated diffusion.
increases the rate of facilitated diffusion for glucose and other monosaccharides.
in the absence of insulin, only ______ and ______ cells are capable of absorbing sufficient amounts of glucose via the facilitated transport system
neural and hepatic
plants form ______ and ________ from glucose
starch and cellulose
2 forms of starch
amylose and amylopectin
the dissolved inorganic ions inside and outside the cell.

assist in the transport of substances entering and exiting the cell by creating electrochemical gradients across membranes.

can give strength to a matrix, such as hydroxyapatite in bone.

act as cofactors
a nonprotein component that assists enzyme or protein function
organic cofactors. often vitamins or vitamin derivatives.
reversibly bind to a specific enzyme, and transfer some chemical group to another substrate.

Cosubstrate is then reverted to its original form.
what distinguishes cosubstrates from normal substrates?
the cosubstrate reverts to its original form.
an enzyme w/out its cofactor is called _________
an apoenzyme
an enzyme w/ its cofactor is called _________
the classic indication of a competitive inhibitor
overcoming inhibition by increasing substrate concentration
zymogen / proenzyme
an inactive form of enzyme. specific peptide bonds are cleaved to irreversibly activate them.
positive cooperativity
the first substrate changes the shape of the enzyme, allowing other substrates to bind more easily

at low substrate concentrations, small increases in substrate concentration increase enzyme efficiency as well as reaction rate.
lyase / synthase
enzyme that catalyzes addition rxns w/out use of energy
ligase / synthetase
enzyme that catalyzes addition rxn, but requires energy from ATP or some other nucleotide
an enzyme which phosphorylates something
an enzyme which dephosphorylates something
molecular synthesis
molecular degradation
substrate level phosphorylation
glycolysis and Kreb cycle.

the formation of ATP from ADP using the energy released from the decay of high energy phosphorylated compounds as opposed to using the energy from diffusion.
acetyl CoA
produced inside the mitochondrial matrix from pyruvate in a rxn that produced NADH and CO2

a coenzyme which transfers two carbons from pyruvate to the 4-carbon oxaloacetic acid
Each turn of the Kreb cycle produced:
1 ATP, 3 NADH, 1 FADH2, 2 CO2

oxaloacetic acid reproduced to start cycle over again
fatty acids and amino acids enter metabolic pathway as:
acetyl CoA
glycerol of triglyerides is converted to _______
proton-motive force
the proton gradient across the inner membrane of the mitochondria
oxidative phosphorylation
production of ATP through the propulsion of protons across the mitochondrial membrane through ATPase
products and reactants of cellular respiration
glucose + O2 --> CO2 + H2O
a series of DNA nucleotides that codes for the production of a single polypeptide or mRNA, rRNA, or tRNA
regions of eukaryotic DNA that are being actively transcribed by a cell
tightly packed regions of eukaryotic DNA that are not actively transcribed.

repetitive sequence DNA found here
the entire DNA sequence of an organism
The Central Dogma
DNA --> RNA --> protein
each nucleotide is bound to the next by a __________
phosphodiester bond
the end 3' carbon is attached to _______
an -OH (hydroxyl) group
the end 5' carbon is attached to a __________
phosphate group
a group of proteins that governs DNA replication
SSB tetramer / helix destabilizer proteins
prevent the single strand in the loop from folding back onto itself
one of the subunits in DNA polymerase that proofreeds and removes / repairs nucleotides on the strand
repeated nucleotide units on the end of eukaryotic chromosomal DNA that protect the chromosomes from being eroded through repeated rounds of replication
a sequence of DNA nucleotides that designates a beginning point for transcription
consensus sequence
the most commonly found nucleotide sequence of a promoter recognized by the RNA polymerase of a given species
variation from the consensus sequence causes...
causes RNA polymerase to bond less tightly and less often to a given promoter, which leads to those genes being transcribed less frequently.
transcription requires a _________, while replication requires a ___________
promoter, primer
template / antisense strand
the DNA strand which is transcribed.
coding / sense strand
DNA strand which is not transcribed. protects its partner against degradation
activators and repressors
proteins which regulate gene expression at the level of transcription.

bind to DNA close to the promoter and activate or repress the activity of RNA polymerase
the genetic unit usually consisting of the operator, promoter, and genes that contribute to a single prokaryotic mRNA
activators and repressors are often allosterically regulated by...
small molecules such as cAMP
regulatory proteins in eukaryotes. function similar to activators and repressors, but act at greater distance from the promoter.
primary transcript
the initial mRNA nucleotide sequence arrived at through transcription
the primary transcript is processed in 3 ways:
1) addition of nucleotides
2) deletion of nucleotides
3) modification of nitrogenous bases
5' cap
serves as an attachment site in protein synthesis and as a protection against degradation by exonucleases
poly A tail
the polyadenylated 3' end protecting against degradation by exonucleases
a complex formed from snRNPs associating w/ proteins

recognize nucleotide sequences at the end of introns and excise introns, splicing the exons together
restriction enzymes
cut nucleic acid at certain nucleotide sequences along the strand
reads the same backwards and forwards.

typically, a restriction site will be palindromic
recombinant DNA
artificially recombined DNA
a plasmid or infective virus that is used to place recombinant DNA into a bacterium
the radioactively labeled complementary sequence of the desired DNA fragment
complementary DNA (cDNA)
mRNA is reverse transcribed using reverse transcriptase

adding DNA polymerase to cDNA produces a double strand of the desired DNA fragment w/out introns.
polymerase chain reaction (PCR)
1) DNA heated to denature
2) cooled --> primers anneal to complementary ends of DNA
3) polymerase added w/ supply of nucleotides --> new DNA
southern blot
identifies fragments of known DNA in a larger population of DNA
northern blot
identifies fragments of known RNA in a larger population of RNA
restriction fragment length polymorphism (RFLP)
identifies individuals (as opposed to genes)

based on premise that DNA of different individuals possesses varying distances btwn restriction sites
more than one series of three nucleotides may code for any amino acid
any single series of three nucleotides will code for one and only one amino acid
start codon

acts as a codon for the amino acid methionine.
stop codons

U Go Away, U Are Away, U Are Gone
tRNA sequesters the amino acid methionine and settles it at the P site. this is the signal for the large subunit to join and form the initiation complex.
an elongation step in which the ribosome shifts 3 nucleotides along the mRNA toward the 3' end.
stop / nonsense codon reaches A site. proteins known as release factors bind to the A site allowing a water molecule to add to the end of the polypeptide chain
Proteins injected into the ER lumen are destined to become __________
membrane-bound proteins
signal peptide
a 20 amino acid sequence near the front of the polypeptide that is recognized by a protein-RNA signal-recognition particle
signal-recognition particle
carries the ribosome complex to a receptor protein on the ER. protein grows across the membrane, where it is released into the lumen or remains partially attached to the ER.
physical or chemical mutations that increase the frequency of mutation above the frequency of spontaneous mutation.
point mutation
a mutation that changes a single base-pair of nucleotides in a double strand of DNA.
base-pair substitution mutation
one type of point mutation in which one base pair is replaced by another
transition mutation
a base-pair substitution in which A-T is switched for G-C or the opposite
transversion mutation
a base-pair substitution that involves a reversal of the same base pairs.
missense mutation
a base-pair mutation that occurs in the amino acid coding sequence of a gene
neutral mutation
a mutation that causes no change in protein function
silent mutation
a mutation in which the amino acid is not changed
frameshift mutation
results when deletions or insertions occur in multiples other than 3. result in nonfunctional protein.
nonsense mutation
a mutation in which a base-pair substitution or an insertion or deletion creates a stop codon
occurs when a DNA fragment breaks free of one chromosome and incorporates into a homologous chromosome
when a segment of DNA from one chromosome is inserted into another chromosome
the orientation of a section of DNA is reversed on a chromosome
DNA segments can excise themselves from a chromosome and reinsert themselves at another location
wild type
the original state of the organism
forward mutation
changes the organism even more from its original state
backward mutation
reverts the organism back to its original state
stimulate normal growth in human cells
mutated proto-oncogenes that cause cancer
mutagens that cause cancer
globular proteins around which sections of DNA that are not in use are wrapped
formed from 8 histones wrapped in DNA
the entire DNA / protein complex
condensed chromatin. cannot be transcribed in this form
chromatin that can be uncoiled and transcribed. only coiled during nuclear division
which 2 cell types remain in G0 permanently?
neurons and muscle cells
the G2 checkpoint checks for ____________
mitosis promoting factor (MPF)
part of the spindle apparatus. microtubules radiating from the centrioles
a group of proteins located toward the center of the chromosome from which the kinetochore microtubules grow
a structure of protein and DNA located at the centromere of the joined chromatids of each chromosomes
the split of sister chromatids during anaphase
spermatogonium / oogonium
diploid. germ cells b/f undergoing meiosis.
primary spermatocyte / oocyte
the germ cell after replication occurs in the S phase of interphase
secondary spermatocyte / oocyte
haploid. germ cells after cytokinesis following telophase I.
reduction division
describes meiosis I
if during anaphase I or II the centromere of any chromosome does not split.
protien coat on a virus
a mature virus outside the host cell
how viruses are different from living organisms
1) require host to reproduce
2) do not metabolize organic nutrients (use ATP from host)
3) not separated from external environment by membrane
4) possess either DNA or RNA, but never both
5) can be crystallized w/out losing ability to infect
a site on the host onto which the virus attaches. usually a specific glycoprotein on the host cell membrane.
a virus that infects bacteria. nucleic acid injected through the tail after viral enzymes have digested a hole in the cell wall.
lytic infection
cell produces new viruses until it bursts
eclipse period
the period from infection to when the first fully formed virion appears
latent period
the period from infection to lysis
virulent virus
a virus following a lytic cycle
lysogenic infection
viral DNA is incorporated into the host genome, or

DNA is reverse transcribed from RNA and then incorperated into host's genome
temperate virus
a virus in a lysogenic cycle
a virus that is dormant / latent. viral DNA is incorporated into host DNA
a dormant / latent virus whose host cell is a bacterium
plus-strand RNA
proteins can be directly translated from the RNA.
carry reverse transcriptase in order to create DNA from RNA. DNA is then incorperated into the genome of the host cell.
minus-strand RNA
the complement to mRNA. must be transcribed to plus-RNA before being translated
small rings of naked RNA w/out capsids. only infect plants
naked proteins. capable of reproducing themselves, w/out DNA or RNA
bind to a viral protein
cytotoxic T-cell
destroy infected cells
an injection of antibodies or an injection of a nonpathogenic virus w/ the same capsid or envelope, that allows the host immune system to create its own antibodies
have similarities to eukaryotes

unlike bacteria, the cell walls are not made from peptidoglycan
fixing CO2
reducing it and using the carbon to create organic molecules through the Calvin cycle
organisms capable of using CO2 as their sole source of carbon
use preformed, organic molecules as their source of carbon
organisms that use light as their energy source
organisms that use oxidation of organic or inorganic matter as their energy source
nitrogen fixation
the process by which N2 is converted to ammonia
creates nitrates, which are useful to plants, from ammonia
inclusion bodies
granules of organic or inorganic matter that may be visible under a light microscope
having both polar and nonpolar regions.

describes phospholipids, glycolipids, etc.
a spherical structure formed from amphipathic molecules in an aqueous solution.
a vesicle surrounded and filled by aqueous solution. contains a lipid bilayer.
integral / intrinsic proteins
amphipathic proteins that transverse the membrane from the inside of the cell to the outside
peripheral / extrinsic proteins
situated entirely on the surfaces of the membrane. ionically bonded to integral proteins or the polar group of a lipid
role of cholesterol in membranes
moderates membrane fluidity
reduce fluidity of the membrane in prokaryotes
Brownian motion
random movement of molecules
chemical concentration gradient
a gradual change in concentration of a compound over a distance
electrical gradient
applies to molecules w/ a charge.

points in the direction that a positively charged particle will tend to move.
semipermeable membrane
slows, but does not stop, diffusion
two aspects of a compound that affect its semipermeability:
size and polarity
passive diffusion
diffusion in which molecules move through leakage channels across the membrane due to random motion
transport / carrier proteins
proteins embedded in the membrane that are designed to facilitate the diffusion of specific molecules across the membrane
facilitated diffusion
diffusion occurs down electrochemical gradient through carrier proteins
selectively permeable
the ability of a membrane to select btwn molecules of similar size and charge using facilitated diffusion
active transport
movement of a compound against its electrochemical gradient. requires expenditure of energy in the form of ATP.
makes up the cell wall
gram-positive bacteria
stain purple b/c they have thick peptidoglycan cell wall that prevents the gram stain from leaking out.
periplasmic space
the space btwn the plasma membrane and the cell wall in gram+

the space btwn the two plasma membranes in gram-
gram-negative bacteria
appear pink when stained b/c thin peptidoglycan cell wall allows most of gram stain to be washed off.

have second phospholipid bilayer outside cell wall. it contains lipopolysaccharides which protect from antibodies and antibiotics
short tenticles which attach a bacterium to a solid surface

not involved in cell motility
bacterial flagella are composed of _______
source of energy for flagellum propulsion
energy comes from a proton gradient rather than by ATP
binary fission
bacterial asexual reproduction.

works like DNA replication.
a small circle of DNA that exists and replicates independently of the bacterial chromosome
the transfer of a replicated plasmid through a sex pilus btwn two bacteria
F plasmid / fertility factor
a bacterial DNA sequence that codes for the sex pilus that allows conjugation
R plasmid
donates resistance to certain antibiotics
the process by which bacteria may incorporate DNA from their external environment into their genome
capsid of bacteriophage mistakenly encapsulates a DNA fragment of host cell, then injects harmless bacterial DNA fragments into host cell.
the virus that mediates transduction
allows gram-negative bacteria to lay dormant when there is a lack of nutrients.

must be activated b/f it can germinate and grow. endospore activated by heating. germination triggered by nutrients.
eukaryotic heterotrophs that obtain their food by absorption rather than by injestion.
to live off dead organic matter
fungal cell walls.

perforated to allow for cytoplasmic streaming
septa are made of _________
the polysaccharide chitin
multiply branched threadlike structures of the fungal growth state
a tangled mass of hyphae
fungal DNA state is mostly:
haploid stage predominates, and is the fungal growth state.
haploid structures that give rise to new mycelia.
single-celled fungi. rarely produce sexually by producing spores.
budding / sexual fission
a small cell pinches off from the single parent cell.

the most common form of asexual reproduction in yeast.
the two mating types of mycelia:
+ and -
when does asexual vs. sexual reproduction occur in fungi?
asexual reproduction occurs when conditions are good, sexual reproduction occurs when conditions are tough
nuclear pores
RNA can exit nucleus through nuclear pores, but DNA cannot
proteins on the particulate matter bind to proteins on the cell --> matter is engulfed

only occurs in a few specialized cells
extracellular fluid is engulfed by invagination of the cell membrane.

performed in most cells, and in a random fashion; nonselective
receptor mediated endocytosis is associated w/ which protein
how does phagocytosis differ from receptor-mediated endocytosis
the purpose of receptor mediated endocytosis is to absorb the ligands

in phagocytosis, the ligands exist only as signals to initiate phagocytosis of other particles
cisternal space / ER lumen
the space inside the ER
in the Golgi apparatus, proteins are distinguished based upon which 2 things?
the signal sequence and carbohydrate chains
if a protein doesn't have a signal sequence,...
they are packaged into secretory vesicles and expelled from the cell
secretory vesicles
protein filled vesicles which expel proteins from the cell through exocytosis

may also contain enzymes, growth factors, or extracellular matrix components

act as the vehicle w/ which to supply the cell membrane w/ its integral proteins and lipids, and as a mechanism for membrane expansion
smooth ER
produces triglycerides.
cholesterol formation --> steroid production
produces phospholipids
detoxification of foreign substances
self-replicating (vs. budding off membranes)

detoxification, oxygen concentration regulation, synthesis and breakdown of lipids, metabolism of nitrogenous bases and carbohydrates.
squeeze the membrane together in phagocytosis and cytokinesis
the major portion of each eukaryotic flagellum and cilium containing microtubules in a 9 + 2 arrangement
the protein which makes up the cross bridges connecting each of the outer pairs of microtubules to their neighbor.

allows for movement of microtubules --> movement of flagella and cilia
prokaryotic flagella are made from ______
a thin strand of a single protein called flagellin
the major microtubule-organizing center in animal cells
function in the production of flagella and cilia, but are not necessary for microtubule production
the major component of microfilaments is __________
cytoplasmic streaming
responsible for amoeba-like movement. caused by microfilament movement.
tight junctions
act as fluid barrier around cell
join two cells at a single point.
gap junctions
tunnels btwn cells allowing for the exchange of small molecules and ions.
the structural protein that gives cartilage and bone their tensile strength
axon hillock
generates an action potential in all directions if the electrical stimulus is from the signal received at the dendrites is great enough
action potential
a disturbance in the electric field across the membrane of a neuron
the resting potential is established by...
an equilibrium btwn passive diffusion of ions across the membrane and the Na/K pump
voltage gated sodium channels open, allowing Na to flow into the cell, reversing the polarity of the membrane potential so that it is positive inside relative to the outside
voltage gated sodium channels close, voltage gated potassium channels open. K+ flows out of the cell making the inside more negative.
inside of membrane becomes more negative than the resting potential b/c potassium channels are slow to close.
electrical synapses
composed of gap junctions btwn cells. transmit signal faster than chemical synapses and in both directions.
chemical synapse
unidirectional; slowest step in the transfer of a nervous signal. when action potential reaches synapse, Ca2+ flows into cell, causing neurotransmitters to be released into synaptic cleft
Brownian motion
the random motion of molecules. the means by which neurotransmitters diffuse across the synaptic cleft
means by which cell prevents overstimulation: (3 things)
1) neurotransmitter destroyed by enzyme in matrix of synaptic cleft and its parts recycled by presynaptic cleft

2) neurotransmitter directly absorbed by presynaptic cleft via active transport

3) neurotransmitter may diffuse out of synaptic cleft
second messenger system
binding of neurotransmitter to receptor activates another molecule inside the cell to make changes
electrically insulating sheaths. increases the rate at which an axon can transmit signals.

formed from oligodendrocytes in the CNS

formed from Schwann cells in the PNS
sensory neurons are located ______
dorsally from the spinal cord
motor neurons are located __________
neuron processes (axons and dendrites) that are bundled together
somatic nervous system
designed primarily to respond to the external environment. contains sensory and motor functions. its motor neurons innervate only skeletal muscle.

voluntary control
autonomic nervous system
generally involuntary
"fight or flight" response

part of ANS
"rest and digest" response

part of ANS
the neurotransmitter used by the somatic and parasympathetic nervous systems
the neurotransmitter used by the sympthetic nervous system
epinephrine or norepinephrine
part of the brain integrating subconscious activities
lower brain, consisting of the medulla, hypothalamus, thalamus, and cerebellum
cerebrum / cerebral cortex
the higher brain; stores memories and processes thoughts
the first place light strikes the eye. most bending of light occurs here.
when the ciliary muscle contracts...
the lens becomes more like a sphere and brings its focal point closer to the lens
the image on the retina is _______ and ___________
real and inverted
the colored portion of the eye which creates the opening called the pupil. controls how much light enters the eye.
tympanic membrane
the eardrum. separates the external auditory canal from the middle ear.
detects sound. hair cells and organ or Corti transduce movement into neural signals
semicircular canals
detect orientation and movement of the head
peptide hormones
water soluble, and thus move freely through the blood

have difficulty diffusing through the cell membrane of the effector --> attach to membrane bound receptors instead of diffusing through the membrane
second messenger
activates or deactivates enzymes and/or ion channels and creates a cascade of chemical rxns that amplifies the effect of the hormone
steroid hormones come from...
the adrenal cortex, the gonads, or the placenta
tyrosine hormones
the thyroid hormones and the catecholamines
peptide hormones come from...
pituitary, parathyroid, and pancreas
steroid hormones
require protein transport molecule to dissolve in blood stream

diffuse through cell membrane of effector, combine w/ receptor in cytosol, transported to nucleus where steroid acts on transcription

typical effect is to increase # of a certain protein
where in cell tyrosine derivative hormones are formed:
formed by enzymes in the cytosol or on the rough ER
thyroid hormones
lipid soluble --> carried through blood by proteins.

bind to receptors in nucleus, increasing transcription of genes
controls the release of anterior pituitary hormones
hormones released by the anterior pituitary
human growth hormone (hGH)
adrenocorticotropin (ACTH)
thyroid-stimulating hormone (TSH)
follicle-stimulating hormone (FSH)
leutinizing hormone (LH)
adrenocorticotropic hormone
a peptide which stimulates the adrenal cortex to release glucocorticoids via the secondary messenger system using cAMP. Release stimulated by stress.
stress hormones
thyroid-stimulating hormone
stimulates the thyroid to release T3 and T4 via the second messenger system using cAMP.
promotes milk production of the breasts
hormones produced by the posterior pituitary
oxytocin and antidiuretic hormone (ADH)
increases uterine contractions during childbirth and causes milk to be ejected from the breasts
antidiuretic hormone (ADH) / vasopressin
causes the collecting ducts of the kidneys to become permeable to water, reducing the volume of urine and concentrating the urine.

b/c fluid reabsorbed, increases blood pressure
adrenal cortex secretes:
only steroid hormones; aldosterone and cortisol
mineral corticoids
one type of steroid hormone secreted by the adrenal cortex

affect the electrolyte balance in the blood stream

think aldosterone
one type of steroid hormone secreted by the adrenal cortex

increase blood glucose concentration and effect fat and protein metabolism

think cortisol
a mineral corticoid that acts in the distal convoluted tubule and collecting duct to increase Na and Cl adsorption and K and H secretion.

creates net gain of particles in the plasma, which results in an eventual increase in blood pressure.
a glucocorticoid that increases blood glucose levels by stimulating the creation of glucose and glycogen in the liver.

degrades fat and proteins. a stress hormone
tyrosine derivatives synthesized in the adrenal medulla.

epinephrine and norepinephrine
"fight or flight" stress hormones
T3 and T4
increase the basal metabolic rate (resting metabolic rate)

lipid soluble tyrosine derivatives synthesized in the thyroid
a peptide hormone released by the thyroid gland which decreases blood calcium level by decreasing osteoclast activity.
endocrine hormones of the pancreas:
insulin and glucagon
released when blood levels of carbohydrates or proteins are high.

stimulates storage of carbohydrates as glycogen, fat as adipose tissue, and amino acids as proteins

increases permeability of cells to glucose and amino acids
parathyroid hormone
increases blood calcium levels by stimulating proliferation of osteoclasts
where the sperm matures and is stored until ejaculation
semen is composed of fluid from... (3 things)
the seminal vesicles, the prostate, and the bulbourethral glands
all the eggs of the female are arrested as ___________ at birth
primary oocytes
zona pellucida
a viscous substance secreted around the primary oocyte at puberty
upon stimulation of ________, theca cells secrete ______
LH, androgen
androgen is converted to _________ in the presence of ____________
estradiol (a type of estrogen) in the presence of FSH
a steroid hormone that prepares the uterine wall for pregnancy
luteal surge
just before ovulation, estradiol level rises rapidly, causing an increase in LH secretion. this causes ovulation
bursting of the follicle
corpus luteum
the follicle left behind after ovulation. secretes estradiol and progesterone throughout pregnancy or for 2 wks after ovulation
corpus albicans
a degraded corpus luteum that results if the egg is not fertilized

no longer secretes estrogen or progesterone
once fertilization occurs, the oocyte...
goes through the second meiotic division to become an ovum and releases a second polar body
what stage of development is the egg in when implants in the uterus?
the blastocyst stage
human chorionic gonadotropin (HCG)
a peptide hormone secreted by the egg upon implantation. prevents the degradation of the corpus luteum
cells become determined to give rise to a particular tissue early on.
the specialization that occurs at the end of the development, forming a specialized tissue cell
induction occurs when...
one cell type affects the direction of differentiation of another cell type
mucous cells
secrete mucus to lubricate the stomach walls so that food can slide along easily and to protect the epithelial lining from the acidic environment of the stomach
chief cells
secrete pepsinogen, the zymogen precursor to pepsin
pariental cells
secrete HCl
G cells
secrete gastrin, a large peptide hormone which is absorbed into the blood and stimulates parietal cells to secrete HCl
increases the secretion of all gastric cell types
gastrin and histamine
increase HCl secretion into the stomach
digestion in the small intestine occurs in the __________
absorption in the small intestine occurs in the...
jejunum and ileum
brush border
the microvilli that cover the intestinal wall, increasing surface area
goblet cells
epithelial cells which secrete mucus to lubricate the intestine and help protect the brush border from mechanical and chemical damage
the fluid in the duodenum has a pH of _______ due to _______
6 due to bicarbonate ions secreted from the pancreas
all enzymes released by the pancreas are _________
trypsin and chymotrypsin
degrade proteins into small carbohydrates
produced by the liver and stored in the gall bladder

emulsifies fat, increasing the surface area for lipase
large intestine
water and electrolyte absorption

contains symbiotic E coli bacteria which produce vitamins
glucose is dragged into the enterocyte by __________
in all cells except _______ and ________, glucose is transported down its concentration gradient via facilitated diffusion
enterocytes and cells of the renal tubule
byproduct of gluconeogenesis from proteins
ammonia, which is converted to urea by the liver and then excreted in the urine by the kidney
fatty acids combine immediately once they reach the blood w/ _______
transport triglycerides from the liver to adipose tissue
intermediate and low-density lipoproteins
transport cholesterol and phospholipids to somatic cells
functions of the liver
blood storage, blood filtration (of bacteria), carbohydrate metabolism, fat metabolism, protein metabolism, detoxification, erythrocyte destruction, vitamin storage
when the liver mobilizes fat or protein for energy, the blood...
acidity increases
function of the kidney
to excrete waste products, maintain homeostasis of body fluid volume and solute composition, and to help control plasma pH
urine is created in the kidney and emptied into the ___________
renal pelvis
the renal pelvis is emptied by the _________
the first capillary bed of the nephron
Bowman's capsule and the glomerulus make up the __________
renal corpuscle
holes in the glomerular epithelium through which hydrostatic pressure forces plasma into Bowman's capsule. screen out blood and large proteins from entering Bowman's capsule.
proximal tubule
takes filtrate after Bowman's capsule. where most reabsorption takes place by means of secondary active transport proteins
an integral membrane transport protein that simultaneously transports two different molecules in opposite directions across a membrane
the net result of the proximal tubule is to...
reduce the amount of filtrate in the nephron while changing the solute composition w/out changing the osmolarity
loop of Henle
dips into the medulla from the proximal tubule. functions to increase the solute concentration, and thus the osmotic pressure, of the medulla.
permeability of descending loop of Henle
permeable to water, but not to salts
permeability of ascending loop of Henle
impermeable to water, permeable to salts
distal tubule
reabsorbs Na+ and Ca2+ while secreting K+, H+, and HCO3-

net effect is to lower filtrate osmolarity
acts on distal tubule cells to increase sodium and potassium membrane transport proteins
increase the permeability of the collecting tubule to water. makes collecting duct permeable to water
juxtaglomerular apparatus
monitors filtrate pressure in the distal tubule
filtration occurs in the _______
renal corpuscle
reabsorption and secretion occurs mostly in the ___________
proximal tubule
concentrates solute in the medulla
loop of Henle
distal tubule enters into the __________
collecting duct
concentrates the urine
collecting duct
pneumonic for ADH
Always Digging Holes (in the collecting duct)
secreted in the juxtaglomerular apparatus. stimulates the adrenal cortex to secrete aldosterone.
occurs when the ventricles contract
occurs during relaxation of the entire heart and then contraction of the atria
vagus nerve
innervates the SA node, slowing the contractions of the heart
which part of the cardiovascular system is wrapped in smooth muscle
arteries and arterioles
skeletal muscle. innervated by phrenic nerve. creates negative gauge pressure in the thoracic cavity when contracted.
prevents food from entering the trachea during swallowing
the oxygen dissociation curve is shifted to the right by... (3 things)
an increase in carbon dioxide pressure, hydrogen ion concentration, or temperature
a shift of the oxygen dissociation curve to the right indicates...
a lowering of hemoglobin's affinity for oxygen
most carbon dioxide is carried through the blood in what form?
as a bicarbonate ion
the bicarbonate ion formation is governed by the enzyme ________
carbonic anhydrase
when bicarbonate moves into the erythrocyte, __________ moves out
fluid is propelled through the valves in 2 ways:
smooth muscle contracts, and skeletal muscle squeezes during movement
transports fatty acids and steroids, acts to regulate osmotic pressure of blood.
the majority of leukocytes are _________
T helper cells
assist in activating B-lymphocytes as well as killer and suppressor T cells.
the lumen of the sarcoplasmic reticulum is filled w/:
the myosin head is released from the active site when...
ATP attaches to the myosin head
the force of a contracting muscle depends upon... (2 things)
the number and size of the active motor units, and the frequency of action potentials
an oxygen storing protein similar to hemoglobin, but having only one protein subunit.
slow-twitch muscle fibers
red from large amounts of myoglobin. contain large amounts of mitochondria.

split ATP at a slow rate --> slow to fatigue, but also have a slow contraction velocity

postural muscles
fast-twitch A muscle fibers
split ATP at a fast rate --> contract rapidly.
fast-twitch B muscle fibers
low myoglobin content, contract rapidly, contain large amounts of glycogen
"growth" of new muscle
does NOT undergo mitosis

when exposed to forceful, repetitive contractions, diameter of muscle fibers increases, number of sarcomeres and mitochondria increases, sarcomeres lengthen.
skeletal muscle
multinucleated. under voluntary control. striated.
cardiac muscle
striated. involuntary. mononucleated. separated by intercalated disks containing gap junctions. mitochondria larger and more numerous than in skeletal muscle.
action potential plateau
the action potential of cardiac muscle exhibits a plateau after depolarization. the plateau is created by slow voltage-gated calcium channels which allow calcium to enter and hold the inside of the membrane at a positive potential difference.

plateau lengthens the time of contraction.
smooth muscle
involuntary, innervated by autonomic nervous system. mononucleated.

contain intermediate filaments attached to dense bodies spread throughout the cell. contraction of actin and myosin causes intermediate filaments to pull the dense bodies together.
spongy bone
contains red bone marrow.
compact bone
hold yellow bone marrow.
Haversian canals
tunnels burrowed by osteoclasts in compact bone
concentric rings formed by osteoblasts
canals through which osteocytes trapped btwn the lamellae exchange nutrients
Volkmann's canals
crossing canals which connect Haversian canals
Haversian canals contain...
blood and lymph vessels
osteon / Haversian system
the entire system of lamellae and Haversian canal
most calcium in the blood is...
not in the form of free calcium ions, but is bound mainly by proteins, and to a lesser extent, by phosphates and other anions.
stores most of the body's Ca2+. give bone strength.
give bone strength
flexible, resistant connective tissue. primarily composed of collagen. contains no blood vessels or nerves except in its outside membrane.
avascular (no blood vessels).
embedded by blood vessels, nerves, glands, and hair follicles. Collagen and elastic fibers provide skin w/ strength, extensibility, and elasticity.
mendelian ratio
3:1 ratio dominant to recessive
the expression of a trait
an individual's genetic makeup
the position on respective chromosomes
law of segregation
alleles segregate independently of each other when forming gametes. any gamete is equally likely to possess any allele.
mating relatives. does not change the frequency of alleles, but does increase the number of homozygous individuals w/in a population
mating of nonrelatives which produces hybrids or heterozygotes
law of independent assortment
genes located on different chromosomes assort independently of each other

in other words, genes that code for different traits, when located on different chromosomes, do not affect each other during gamete formation
a map of the chromosomes
Barr body
the inactive X chromosome in an inactive somatic cell
gene pool
the total of all alleles in a population
a change in the gene pool
order of taxonomical classification
kingdom, phylum, class, order, family, genus, species
plants and fungi use _______ instead of _________
divisions instead of phyla
the subphylum vertebrata is in the phylum _________
three domains
bacteria, archaea, and eukarya
all organisms that can reproduce fertile offspring w/ each other
the way in which a species exploits its environment
the organism which can best survive to reproduce fertile offspring.
involves producing large numbers of offspring that mature rapidly w/ little or no prenatal care.

high brood mortality rate.

population growth curves are exponential. found in unpredictable, rapidly changing environments.
small brood size w/ slow maturing offspring and strong parental care.

sigmoidal growth curve which levels off at the carrying capacity.
the process by which new species are formed.

begins when gene flow ceases btwn two sections of a population. factors include geographic, seasonal, and behavioral isolation.
adaptive radiation
occurs when several separate species arise from a single ancestral species.
evolutionary bottleneck
occurs when a species faces a crisis so severe as to cause a shift in the allelic frequencies of the survivors of the crisis.
divergent evolution
when species evolving from the same group maintain a similar structure from the common ancestor
convergent evolution
when species independently evolve similar structures
the occurrence of distinct forms of a phenotype (height, flower color, etc)
a relationship btwn two species
a relationship that is beneficial for both species
beneficial for one species and does not affect the other
when a population is in Hardy-Weinberg equilibrium...
there is no change in the gene pool
requirements of a Hardy-Weinberg equilibrium: (5 things)
1. large population
2. mutational equilibrium
3. immigration or emigration must not change gene pool
4. random mating
5. no selection of the fittest
genetic drift
in small populations, random events cause the death of all members having a certain allele
Urey-Miller experiment
one of the early experiments attempting to recreate the atmosphere of early earth
lipid or protein bilayer bubbles. the first cells are thought to have evolved from them. spontaneously form and grow from fat molecules suspended in water.
the earliest organisms
existed 3.6 billion years ago. probably heterotrophs subsisting on preformed organic compounds.
filled the atmosphere w/ oxygen
photosynthetic bacteria evolved 2.3 billion years ago
organisms whose anus develops from or near the blastopore
a body cavity w/in mesodermal tissue
possess a notocord, pharyngeal slits, a dorsal hollow nerve cord, and a tail
a subphylum of chordata that has the notochord replaced by a segmented cartilage or bone structure. have a distinct brain enclosed in a skull.