physiology final exam

flight costs

higher metabolic rate, cheaper than running or swimming

reasons for flight

migration to food sources and better weather

gliding flight

cannot actively maintain altitude, all vertebrate, some invertebrate

powered flight

flapping, insects, pterosaur, birds, bats

evolution of flight

run stabilization, run-leap-glide, directional control

evolution of bird wing

feathers for insulation, sexual display

tracheal system

land anthropods, hemolymph, spiracles, air pushed in and out of structure, very efficient

book lung

spiders, air bellows in and out, air pushed through

hemolymph

transport nutrients, waste in insects

ganglia neural system

decentralized nervous system, can be overridden by brain, good coordination of limbs, headless insect can survive until starvation, non-myelinated neurons

ant muscles

attach to exoskeleton, gradual transition to joint

synchronous

all muscle contraction controlled by nerve impulse

asynchronous

only initial and every dozen muscle contraction initiated by nerve impulse, brain does less work, brain couldn’t fire enough for flight without this

indirect muscles

not directly connected to wings, attach to pterothroax internally

flight vs reproduction correlation

flight is correlated with reduced reproductive output

tsetse fly

one baby, ovoviviparous, produces milk, 10 days in uterus, 100% of mother’s weight

aphids, hissers

live nymphs containing embryos

bird size

bigger the bird, less energy for transport

long distance migratory birds

oxidative fibers for energy

altricial

shorter incubation, cannot walk straight out of the egg, find babies food

precocial

ready to walk right outside egg,

central nervous system

CNS, brain and spinal cord, thinking, learning, perception

peripheral nervous system

PNS, motor neurons, sensory neurons, somatic nervous system, autonomic nervous system, special senses

insect nervous system

ventral cord in front, simple

cephalopods

most compelx, high order cognitive behavior, 9 brains

neurulation

early embryonic neural system

ommatidia

cornea, lens, accessory structures, poor acuity, good for movement detection ex. dragonflies

simple lens

vertebrates, cephalopods, gastropods; lens, cornea, receptors

simple corneal eye

arachnids, some vertebrates; cornea and receptors

compound eye

insects, crustaceans; receptor and lenses

opsin

light detecting proteins, humans have 3, dragonflies have 30, detect UV

invertebrate polarized vision

reduce glare, increase contrast, navigation, sexual signaling, detecting water

vertebrate polarized vision

fish, birds, few amphibians, reptiles, detect sun height for navigation

audition

air vibrations detected with ear parts

vestibular system

3 orientations, hair cells

gustation

taste system, bind specific chemicals to receptors

olfaction

detection of odorants, chemoreceptors

flehming

horses flip lip upward, detection of pheromones

electroreception

detect electrical signal, social communication, navigation, hunting, degense

magnetoreception

detect earth’s magnetic field, migration, navigation, Fe3O4

echolocation

low light, bats, toothed whales, birds

infrared detection

heat sensors, prey, predator, thermoregulation

bat evolution

evolved 3 times, split 65 MYA

bat skeleton

more rigid and dense

bat skull

changes shape based on diet, fused

bat echolocation

large ears, comes from laryngeal or tongue

pterosaur physiology

endotherm, hunter, big brain, hollow bones, feathers

pterosaur respiration

airsacs, chest movement like a bird, unidirectional flow,

pterosaur food source

fish

pterosaur reproduction

soft leathery eggs, bury underground, reduce drying out and temp changes, altricial baby (helpless)