BIO 3315
what is negative feedback?
a system which returns to a stable point
what is positive feedback?
reinforced deviations from stable points
what is a homeotherm?
animal able to keep body temperature constant
what is a poikilotherm?
animal that's temperature changes with its environment
what is a endotherm?
animal who internally generates their temperature
what is an ectotherm?
animal reliant on external heat generation
what is temperature regulation?
the maintenance of physiological core body temperature by balancing heat generation through heat loss
what is temperature conformity?
animals who can only survive in narrow environment ranges
what are acute physiological changes?
immediate change in response to the environment, which will return to its previous state.
what are chronic physiological changes?
long-term acclimation to a situation, reversible once stimuli is taken away
what are evolutionary physiological changes?
alteration of gene frequencies over multiple generations exposed to a new environment
what are developmental physiological changes?
changes in the physiology of individual animals that occur in a programmed way
what are periodic physiological changes?
changes in physiology of individual animals that occur in repeating patterns
what is the phospholipid bilayer?
phosphate group + lipids
polar, hydrophilic head
non-polar, hydrophobic tail
*Amphipathic is polar and non-polar
what is an integral protein?
protein that are part of the membrane that spans the width and cannot be removed
what is a peripheral protein?
proteins bonded weakly to one side of the membrane. are not attached, but interact with the membrane
what is cholesteral?
aka sterols
located on phospholipids
enhances bilayer cohesiveness allowing it to be more resistant to mechanical stress & temp
what are carbohydrates?
located on the extracellular side of the membrane
attachment sites for proteins and cell recognition sites
what are factors influence membrane fluidity?
ease of motion of phospholipids
saturation of hydrocarbons
what are epithelial cells?
sheet of cells covering cell body surface, organs, or cavity
what is the function of epithelial cells?
compartmentalize different parts of the body
what type of epithelial tissue is this?
squamous
what type of epithelial tissue is this?
cuboidal
what type of epithelial tissue is this?
columnar
what are microvilli?
membrane projections used to increase surface area of epithelial cells
what is a primary structure?
a string of amino acids, "backbone", with strong bonds
22 total genome coding possible
what is a secondary structure?
local folding patterns of amino acids in helix or pleated sheets
what is a tertiary structure?
total 3D structure of a protein including side chains off of an amino acid backbone
what is a quaternary structure?
protein including interactions between multiple protein molecules called subunits
what is ubiquitin-proteasome?
small proteins that tag faulty proteins, and proteasome destroys them
what is proteostasis?
the regulation of balanced/functioning proteomes
maintains body equilibrium
composes and destroys misfolded proteins
what is protein denaturation?
altered/warped 3D structures caused by temperature change and toxins
how are proteins repaired?
molecular chaperones:
channels, transporters, enzymes, receptors, & structural proteins
what are enzymes?
molecules responsible for catalyzing a chemical bond
what influences reaction rate?
amount of given enzyme, dependent on tissues and individual species
ligand-gated
g protein-coupled
enzyme-linked
intracellular receptors
how does an ionotropic receptor work?
ligand binds to receptor on proteins, and opens channels to allow ions to pass through cell membranes
how does a g protein-coupled receptor work?
ligand binds to receptor in membrane, g protein is activated and exerted on intracellular effect
how does an intracellular receptor work?
ligand binding, receptor activation, translocated to the nucleus where DNA is bonded and transcribed.
what is genotype?
underlying genetic condition
what is phenotype?
expressed characteristics of an organism
how do genomes change over time?
accumulation of base changes over time, that can be duplicated into other genes
what is synonymous substitution?
changes in sequence that produce the same amino acid
what is non-synonymous substitution?
changes to the amino acid sequence
how are genes encoded?
DNA transcription -> mRNA -> translation to a protein
what is a promoter?
regulatory region upstream of transcription start site where RNA polymerase binds for transcription
what is an enhancer?
regulatory region affecting gene transcription, not always at the start site
what are transcription factors?
various proteins bind to DNA to help recruit RNA polymerase to transcription start
what is a genome?
full set of genetic material, unchanging
what is transcriptome?
profile of expressed mRNA (based on tissue, environment, aging)
what is proteome?
profile of expressed protein (based on tissue, exposure, aging)
how are cells specialized for tissue-specific functions?
different subsets of genes are expressed in different cell types
what are the different was to study physiology?
"top-down"- overall response -> specific organs, tissues, cells
"bottom-down"- specific organs, tissues, cells -> overall response
what is phenotype plasticity?
ability of an animal with a given genotype to ultimately express different phenotypes
what is polyphonic development?
genetically identical individuals that take on 2+ body forms
what is ultimate mechanisms?
evolutionary explanations for a particular trait/behavior development
what is proximate mechanism?
immediate, underlying causes of biological function/behaviors
what is DNA methylation?
epigenetic modification in which methyl groups attach to DNA influencing transcription
found in cytosines in genome
blocks gene transcription in promoter
what are histone modifications?
post-transitional epigenetic modification in histone proteins
crucial for gene expression
histone methylation vs.. histone acetylation
methylation=closed chromatin
acetylation=open chromatin
what is maternal programming?
impact of a mother's care during the developmental and long-term health of offspring