Exam 3 Flashcards
Animal Development/Fertilization
Diploid zygote which is formed by haploid sperm and egg
Sperm-egg contact activates metablic reaction that _______ embryonic development
triggers
Fertilization in sea urchin includes the ____ reaction
acrosomal
Acrosome at tip of sperm discharges _____, allowing for elongation through jelly coat
hydrolytic enzymes
lock and key recognition ensures
fertilization by right species
Na+ ions flow into egg as result of fusion opening channels, the resulting ______ of egg prevents other sperm from fusing with egg, acting as a _____________
depolarization, fast block to polyspermy
Rise in Ca2+ ions stimulates cortical granules to release contents between pm and viteline layer, forming a _____, which is the ______
fertilization envelope, slow block to polyspermy
Fertilization in terrestrial animals:sperms migrate to the ______, the extracellular matrix of the egg
zona pellucida, slow block
Fertilization in terrestrial animals: sperms pass through ______ rather than jelly coat
folical cells
There is/is not fast block to polyspermy in humans
is not
Cell division that creates a blastula
cleavage
blastula
hollow ball of cells w/ fluid filled cavity (blastocoel)
egg+zygote of many animals develop ______
polarity, defined by distr. of yolk (stored nutrients)
Yolk is more concentrated toward the ____ pole, rather than the ____ pole
vegetal, animal
Based on upper entry point of sperm, shift in animal pole occurs, this is called _____
cortical rotation
complete cleavage of eggs with small or moderate amounts of yolk is said to be
holoblastic
The large amount of yolk in the eggs of birds, reptiles, fishes, insects is a type of incomplete cleavage called
meroblastic
Cleavage planes are usually along ______
animal-vegetal poles
rearranges blastula cells into 3 layered embryo
Gastrulation
______: the development of body shape, occurs through gastrulation and organogenesis
morphogenesis
invagination of cells at vegetal poles forms the
archenteron
the archenteron later becomes the
digestive tube
the opening to the archenteron, the _____, later becomes the anus
blastopore
3 layers
ectoderm-outer layer
endoderm-lines digestive tract
mesoderm-party fills space b/t
organogenesis
germal layers develop into rudimentary organs
Notochord in frogs later replaced by
vertebral column
the neural plate curves inward, forming the neural tube, which later becomes the
central nerv system (brain+spinal cord)
Neural crest cells move to other areas and form
nerves, teeth, skull, bones
key elements of the dev process: cells change shape
reorganization of the cytoskeleton:pinching off of neural plate forms the neural tube
ECM
guides cells into positions
unequal division of cytoplasmic controls
Cytoplasm determination
mesenchyme cells from the _____ give rise to the vertebral column and ribs
somites
the slow block to polyspermy is a result of the of the formation of the
fertilization envelope
In a frog embryo, gastrulation proceeds by involution as cells roll over the
dorsal lip of the blastopore
primitive streak of mammals = ____ of frogs
dorsal lip
human embryo most closely resemble sea urchins because
neither has eggs with a large store of yolk and both have holoblastic cleavage
sensor–>sensory input–>integration–>motor output–>effector these are the
stages of information processing
sensory input detects
stimuli
PNS consists of neurons (bundles into nerves) which transmit info to and from the
CNS
integration:CNS includes
brain and nerve cord
motor output: carry info to
motor neurons, trigger muscle or gland activity
neurons/dendrites
highly branched extensions that receive signals from other neurons
neurons/axons
long extentions that transmit signals to other cell synapsis
synapse
Junction b/t axon and another cell, Neurotransmitter (NT) passes info across synapse
membrane potential
voltage difference across plasma membrane
At equil K+ is __ inside cell, Na+ cell ____ outside cell because Na-K pump
high, high
the inside of the cell is more ___ compared with the outside
negative
at resting potential most of the voltage gated Na+ and K+ channels are
closed
Action potential only travel one direction toward
synaptic terminal
Speed of AP increases with:
myelin sheath
Ap occurs at
nodes
AP opens Ca2+ chanell causing vesicles to
bind w/ axon membrane and release NT
Types of NT: acetylcholine
shortage assoc w/ alzheimers
Types of NT: biogenic amines
norepeprehine, dopamine, seratonin. Antidepressants prevent breakdown of these. Ecstacy increases all 3 above.
LSD alters action of
seratonin
neuropeptides (short chains of amino acids)
endorphines effect pain and perception and influence emotion.
Types of NT:amino acids
glutamate:long term memory function
organization of nervous system examples
unspecialized-no brain or ganglia
hydra-nerve net
sea star-nerve ring
Specialized-CNS:brain, ganglia
Role of sodim-potassium pump in establishing cells membrane potential
maintains steep gradients of higher K+ inside cell and higher Na+ outside
After the rapid depolarizatio of an action potential, the fall in membrane potential occurs due to the
opening of voltage-gated K+ channels and the closing of Sodium inactivation gates
Nodes of Ranvier
gaps where Schwann cells abut and AP are generated
movement of AP in one direction along neuron is due to
refractory period, when sodium inactivation gates are still closed
signal transmission is faster in myelinated axons because
AP can jump from node to node along the insulating myelin sheath
main effect of NT GABA
increase pain
Brain:gray matter
neuron cell bodies, dendrites, unmyelinated axons
Brain: white matter
bundles of myelinated axons
Spinal cord conveys info from
brain to PNS
Spinal cord produces _____ (ind of brain)
reflexes (auto response to stimuli)
cerebrospinal fluid provides
internal cushion for central canal and ventricles
PNS-afferent sensory neurons
hear, taste, touch
PNS-efferent do something
motor system:voluntary, autonomic-involuntary
PNS-efferent-autonomic
sympathetic-fight or flight
parasympathetic-return to rest (rest and digest)
these are antagonistic controls
enteric system
digestion
Brain:Brain stem
Mpm
mid brain, pons, medulla oblongata
brain:diencephalon
epithalamus, thalamus, hypothalamus
brain:cerebellum
coordinating movement, perceptual and cognitive functions
brain:cerebrum
largest and most complex part of brain, memory, attention, language
Brain:corpus callosum
communication b/t r and l cerebral corticles
Brain: L hemisphere
language, math, logic
Brain: R hemisphere
pattern recog, nonverbal thinking, emotional processing
Cerebral Cortex:outer portion of brain
4 lobes:frontal, temporal, occipital, parietal
Neuron structure and synaptic connections are established
during embryonic development
snyaptic connections increase w
high activity
mechanoreceptors
sense physcial deformation: pressure, stretch, motion, sound
Parts in ear MIS
malleus (hammer), incus (anvil), stapes (stirrup)
Transmit sound pressure waves to small bones MIS, which conduct waves to inner ear by
membrane called oval window
Most invertabrates use ____ for equil
statocysts
Electromagnetic receptors detect
light, electricity, magnetic
Eyes: rods and cones
rods: light intensity
cones: color
Light alters retinal from cis to ___ isomer, change in shape opens Na+ channels
trans
amacrine and ganglian cells integrate signals from bipolar and horiz cells and send signal to
visual cortex
chemoreceptor
sense solute concentration: smell, taste
smell: odorants bind w chemoreceptor on membranes of
olfactory cilia
Taste sweet, sour,…
bitter, salty, umami
taste and smell are ind systems that interact
75% taste is from oderants traveling from mouth to nasal cavity
Thermoreceptors
responses to heat and cold
sensory perception is
the interpretation of a stimulus according to the region of the brain that receives the nerve impulse
electromagnetic receptors are/are not present in human skin?
are not
function of the 3 bones in the middle ear is to
transmit pressure waves to the oval window
fish can perceive pressure waves with
lateral line system containing mechanoreceptor units
lat line of fish, statocysts, and cochlea in your ear all use ___ as mechanoreceptors
hair cells
when you make a muscle you are
contracting a flexor
inductive reasoning
conclusions based on individual cases
strong induction
what everyone’s seen (all crows black)
weak induction
what you’ve seen
deductive reasoning
if, then logic. general premise to make specific prediction
steps of scientific method have multiple starting points or
circular feedback
hypothesis:proposed answer to well framed question
testable, falsifiable
Theory is
broader in scope than hyp, general and can lead to new hyp, supported by large body of evidence
Darwins observations
organisms are not static, wel matched to env, vary traits, offspring inherit traits
Evolve by Natural Selection
ind w favorable traits survive and reproduce more often
pop is the smallest group that can
evolve over time
homology
similarity in characteristic traits from ancestry: Forelimb of cat, human, bat, whale
Leaf modifications
Pitcher (collect water)
Trap (venus fly)
coloration
herbivore protection (spines-cactus)
speciation is the process where
1 splits into 2
microevolution
change in allele freq of pop
macroevolution
broad patter over time, adaptive change
bio species concept
pop w/ genetic exchange and genetically isolated. based on interfertility not physical similarity, based only on gene flow
morphological species concept
body shape, size, structure-relies on subjective criteria
ecological species concept
species defined by ecological niche: eg-resource use in bio community-dessication tolerance for similar looking frogs
phylogenetic species concept
smallest group that share a common ancestor and forms one branch on the tree of life
allopatric speciation
geographic barriers restricting gene flow
geog process splits pop by way of
mountains, glaciers, land bridges, grand canyon
geog barriers lead to speciation due to
diff mutations, genetic drift
polyploidy
duplication of chromosomes
chromosomal rearrangement
blocks of genes copied together
genetic drift
chance events that alter allele freq
