Afferent
into the central nervous system
Efferent
out of the central nervous system
cells involved in hearing
hair cells with stereo cilia and 1 kinocilium
Process of hearing, 6 steps
1) stereo cilia bend due to a pressure wave. 2) potassium channels open. 3) membrane depolarizes. 4) Calcium flows in. 5) Synpase vesicles fuse. 6) Neurotransmitters are released.
3 parts of the ear
outer, middle, inner
Outer Ear
tube that funnels, stops at the ear drum. Once it reaches the ear drum, three bones get tapped to send vibrations thru
Middle Ear
3 bones send wave patterns (via taps) into ovular window on the side of the chochlea
Inner Ear
chochlea, full of fluid, now have liquid waves. Fluid moves the stereo cilia which opens channels to flood axons of sensory neurons. Amount of bend determines how “much” signal gets sent.
Vision
electrical signals from the optic nerve into afferent sensory nerves.
Vision in Insects
ommatildia - how much light comes in, great at picking up motion due to black and white. Could be btwn 100-10,000 “eyes” all in black and white for motion.
blindspot
the optic nerve runs into the optic disk and there are no cells on the optic disc to perceive light so we cannot see anything.
Smell
mucuos layers trap different particles (olfactory senses)
Optimum foraging theory
only eat special stuff (kobe steak for us) when everything is excess. Otherwise eat everything you can.
Pheromone
molecule that you send out to be picked up by another member of the same species
Muscles
muscle fibers - myofibrils that are striated due to sarcomeres.
sarcomere
actin and myosin working together, all muses pull, never push
actin
thin, does not move
myosin
thick, moves forward and backward “power stroke”
4 Steps of muscle contractions
1) ATP binds. 2) ATP hydrolyzed (becomes ADP) 3) P is released (power stroke). 4) ADP is released.
Cardiac Muscles
1-2 nuclei, branched myofibrils, and involuntary contractions (only found in the heart)
Smooth Muscles
1 nuclei, branched myofibrils, and involuntary contractions (all other involuntary muscles other than heart)
Skeletal Muscles
account for 60% of all muscles, multinucleated, unbranched myofibrils, and voluntary contractions.
Fast twitch muscle fibers
fast rate of contraction, little oxygen and wear out really quickly. fermentation (glycolosis) gives you 2 ATP very quickly.
Slow twitch muscle fibers
slow rate of contraction, very good endurance, tons of myoglobin (holds oxygen) slow but almost constant energy. oxidative phosphorolation (30 ATP)
hydrostatic skeleton
coordinated movements (some circumferential muscles and some longitudinal.
exoskeleton
muscles hold on to bones at different joints
bones
calcium phosphate (found in extra cellular matrix)
cartilage
carbs and proteins (found in extra cellular matrix)
tendons
collagen (muscles to bones)
ligaments
collagen (bones to bones)
hormones
long distance communication through the blood
autocrine
sending signals to the same cell
paracrine
sending signals to neighboring cells
endocrine
sending signals through blood and lymph
neural
sending signals through neurons
neuroendocrine
multi steps of signals
3 different types of hormones
polypeptides, amino-acid derivatives, and steroids
polypeptide hormones
bonds btwn amino acids
amino-acid derivative hormones
started as amino acids but broken down and sent off.
steroids as hormones
lipid soluble (hydrophilic) and pass through membrane easily (receptors inside of the cell)
cascade effect
receptor gets filled up, changes shape, sends signals to inside of the cell but the original molecule stays on the outside of the cell.
Broad spectrum antibiotics
target the cell wall of the antigen
Number 1 side effect of antibiotics
diarrhea because bacteria doesn’t slow down to break down the food so everything just slides right through. Bacteria is 10x the human cells in and on the body
10% efficiency in levels of producer/consumer
so 10 pounds of corn gives you one pound of cow and ten pounds of cow gives you one pound of human…100 pounds of corn for 1 pound of human
Understanding the Endocrine System
all about homeostasis, signals move in and out and help your body respond to the environment
Sexual Reproduction
Meiosis (2n = 4x n) interphase
Asexual Reproduction
Mitosis (2n = 2x 2n) 1)budding - a piece comes off and its genetically identical. 2)fission - splitting, it breaks in half. 3)parthenogenesis - unfertilized eggs develop into off spring and they are an exact copy of DNA
3 different reproductive strategies
oviparous, viviparous, ovoviviparous
oviparous
laying eggs
viviparous
live births
ovoviviparous
egg is kept inside until ready to be on its own
External reproduction
females release eggs into the environment, male releases sperm towards the egg and both are heavily dependent on timing and location
Immune Systems, 3 steps
1) keep bad stuff from entering the cell at any opening. 2) identify the problem. 3) kill anything that shouldn’t be in the cell
Innate immune systems
constant, neutrophils, mast cells, and macrophage
neutrophils
kill things
mast cells
control blood flow
macrophages
kill and recruit help (phagocytosis)
RBC’s
oxygen transport to tissue via iron, carbon dioxide from tissues back to lungs. Main goal is cellular respiration (12-15 times multiplier
WBC’s
immune functions: neutrophils, mast cells, macrophages, and lymphocytes
lymphocytes
adaptive and very specific. T-cells, B-cells, and NK cells
Antigens
any invader that initiates the immune system
T-cells
mature in the thymus and triggered by B-cells
B-cells
mature in the bone marrow and are the first to recognize antigens. Once they are activated they differentiate into memory cells and a clone army
4 rules for lymphocytes
1) all are produced in the bone marrow. 2)mature in different places. 3) circulate through blood and lymph. 4) Need activation via antigens
What happens for HIV to become AIDS?
T-cell level drops to low so you loose immunity
Vaccines
essentially preloading your immune system. This preps your adaptive immune system.
subunit vaccines
take a little piece, introduce it to your body, and then develop memory cells. EX: hepatitis B and the flu
inactivated vaccines
chemically kill (deactivate) the virus and then introduce the entire virus. EX hepatitis A and polio
attenuated vaccines
weakened or diluted viruses
Allergies
over-reactions to antigens
Allergens
specific antigens that cause allergies
Autoimmune disease
body thinks itself is an antigen and attacks itself.
Ecology
relationship between species and environment
Cost benefit analysis
what does it cost me and what do i get out of it. ALL driven by food and sex
Who/What/Where should I…Eat
optimal foraging theory (whats its cost? is it in excess?)
Who/What/Where should I…Mate with?
Intersex - female chooses the mate. Intrasex - males fight other males for rights to females
Who/What/Where should I…Live
migrate or settle?
Who/What/Where should I…communicate
pheromones? (ants) dances? (bees) talk? (humans)
Who/What/Where should I…cooperate
altruism - give something to the group and not get anything back
Reciprocal altruism
giving back to someone else for the betterment of the group at the cost of the individual
Levels of organization
molecules, tissues/organs, individuals, populations, community, and ecosystems
populations
groups of same species (reproduction is possible)
community
group of populations in a given area
ecosystems
groups of communities
4 essentials
food, water, shelter, and sex
population density
4 factors: birth, death, immigration, and emmigration
fecundity
number of females produced by each female
carrying capacity
how much of a population can be sustained?
niche
specific environment for individuals to thrive
competitive exclusion principle
fighting for a resource, winner stays and the loser goes. No 2 organisms fill the same niche at the same time
Keystone Species
species with the most impact on an environment, has a small bio-mass to impact ratio.