EXTRA BIO 2

contain G cells that secrete gastrin, whcih induces parietal cells to secrete more HCl and signals the stomact to contract and mix its content

causes brush border enzymes to secrete disaccharidases 

duodenum secretes enteropeptidase, whcih activtes trypsin

peptide hormone that causes pancreatic enzymes to be released into the duodenum

regulates the pH of the digestive tract by reducing HCl secretion 

it is an enterogastrone (hormone that slows motility through the digestive tract)

stimulates secretion of bile

small intestine with pancreatic lipase

major pigment of bile 

travels to the liver, where it is conjugated and secreted into the bile for excretion

secondary active transport and facilitated diffusion into the epithelial cells lining the small intestine; they then move across the epithelial cells into the intestinal capillaries; a concentrationg radient then lalows simple carbs and amino acids to diffuse into capillaries

an outpocketing that accepts fluid exiting hte small intestine through the ileocecal valve and is the site of the appendix

cuplike structure surrounding the nephron

relaxation of the urethral sphincter in response to increased pressure in the bladder

glomerulus

converts it to urea

reuptake for use in the bod

segments that are horizontal are focused ont eh the identity of teh particles (keep what is needed; lose what is not)

vertical: focused on volume adn concentratoin

amino acids, glucose, water-soluble, vitamins,and salts are reabsorbed along with water

70% reabsorbed

site of secretion for a number of waste products, including hydrogen ions, potassium, ammonia, and urea

permeable only to water adn the medulla has an ever increasing osmolarity

change in permeability; only permeable to salts and not water

increasing amounts are removed as it travels up

thicker diluting segment (cells lining the tube are larger)

cells are larger; contain large amounts of mitochondria, which allow reabsorption of Na+ and Cl- by active transport

responds to aldosterone, which promoes sodium reabsorption

sodium ions are osmotically active particles so water will follow, concentating the urine

responsive to aldosterone and ADH

permeability increases--> water reabsorption

control BP, blood osmolarity, and acid-base balance

distal CT

collecting duct

alters permeability of collecting duct directly, allowing more water to be reabsorbed by making the cell junctions of the duct leaky

papillary layer

reticular layer

sensory cells present at the epidermal-dermal junction; connected to sensory neurons and are responsible for deep pressure and texture sensation within the skin

respond to light touch

respond to stretch

respond to deep pressure and vibration

muscles that contract in cold conditions causing hair to stand up

gap junctions that allow for flow of ions directly between cells

this allows for coordinated muscle cell depolarization and efficient contraction of cardiac muscle

gap junctions allow for progressive depolarization to spread via ion flow across the gap junctions between cells

contains mostly thin flimaents

contains the thick filaments in their entirety, including any overlap with think filaments

contains only thick filaments

• contraction starts at the neuromuscular junction, where the NS communicates with motor neurons
• The signal travels down neuron until it reaches the nerve teerminal, where acetylcholine is released into the synapse

acetylcholine binds to receptors on the sarcolemma, causing depolarization

calcium binds to troponin, causing a change in conformaiton of tropomyosin, allowing exposure of myosin binding sites

release of myosin from actin

if a muscle fiber is exposed to frequent and prolonged summation, it will have insufficient time to relax; the contractions combine, become stronger and more prolonged

have less mitochondria and rely on glycolysis and fermentation to make ATP under most circumstances

cyclindrical shafts called diaphyses that swell at each end to form metaphyses and that terminate in epiphyses

se spongy cores for more effective dispersion of force andpressure at joins; at internal edge is an epiphyseal growth plate, which is a cartilaginous structure and the site of longitudinal growth

a laer of soft tissue that secretes synovial fluid, which lubricates the movement of structures in the joint space

muscle that decreases the angle across a joint

increases or straightens this angle

moves a part of the body away from teh midline

moves part of body toward midline

population measure defined as the proportion of individuals in the population carrying the allele who actually express the phenotype

when 100% of individuals with the allele show symptoms

most but not all show symptoms of the disease

varying phenotypes despite identical genotypes

all individuals with a given genotype express the same phenotype

genes exist in alternative forms called alleles

an organism has two alleles for each gene, one inherited from each parent

the two alleles segregate during meiosis, resuting in gametes that carry only one allele for any inherited trait

if two alleles are different, one is fully expressed and the other is silent

occur when a segment of DNA is copied multiple times in the genome

occur when a segment of DNA is reversed within the chromosome

occur when a segment of DNA is moved from one chromosome to another; small insertion mutations are considered frameshift mutations

occur when a segment of DNA from one chromosome is swapped with a segment from another

• flow of genes between species
• individuals from different species can mate to produce hybrid offspring, which can't reproduce

extreme case of genetic drift in which a small population of a species finds itself in reproductive isolation from other populations as a result of natural barriers, catastrophes, or other bottleneks that drastically and suddenly reduce the size of the population available for breeding

changes in the composition of the gene pool due to chance

loss of genetic variation that may cause reduced fitness of the population

intro of unrelated individuals into a breeding group

The bottleneck effect is a sharp lowering of a population's gene pool because of an environmental, or human-caused, change

the likelihood that two alleles are separated from each other during crossing over

roughly proportional to the distance between the genes on the chromosome

how often an allele appears in a populaiton

ex: if 75 alleles were dominate out of 100, there is a .75 frequency

population is very large (no genetic drift)

no mutations

mating is random

no migration of individuals into or out of the population

genes are equally successful at reproducing

adds knowledge of genetic inheritance and changes in the gene pool to Darwin's original heory

measure of an organism's success in teh population

altruism is a component of inclusive fitnesss that is helping others because it will increase your sucess

suggests that changes in some species occur in rapid bursts rather than evenly over ime

keeps phenotypes within a specific range by selecting against extremes

adaptive pressure can lead to the emergence and dominance of an initially extreme phenotype

two extreme phenotypes are selected over the norm

related concept of dirsuptiv selection that describes the rapid rise of a number of differnt species from a common ancestor that enables animals to occupy certain niches

• temporal isolation (breeding at different times)
• ecological isolation
• behavioral isolation (lack of attraction) 
• gametic isolation (fertilization not possible)

• hybrid inviability 
• hybrid sterility
• hybrid breakdown