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bio 422 exam 2

Terms in this set (125)

prezygotic isolating mechanism and postzygotic isolating mechanism
2 basic mechanism that create and maintain reproductive isolation.
zygote
It is a fertilized egg. It also the unicellular and diploid cell.
prezygotic isolating mechanism
It occurs before a zygote is formed. It prevents a zygotes being made which prevent the egg from being fertilized.
1: Geographical isolation
2: Ecological isolation
3: Temporal isolation
4: Behavioral isolation
5: Mechanical isolation
6: Gametic isolation
different type of prezygotic isolating mechanisms
there're 2 separate groups, whether they're emerging species that are reproductively isolated or truly separate species that are remaining, being reproductively isolated due to being in different place. (allopatry)
Geographical isolation
Emerging groups or more separate species stay separating from each other. They don't reproduce with each other due to subdivision of the habitat. (sympatry)
Ecological isolation
It has to do with different among groups in the timing of reproduction. Even though they may be sympatric and within the same habitat, they're not reproducing at the same time, so they never have the opportunity to reproducing with each other.
Temporal isolation
There're behavioral cues that are unique to particular species that are used in the process of attracting a mate and going through the mating process. It may not be giving off the right behavioral cues so that species don't actually end up selecting each other as mates. (sympatry)
Behavioral isolation
It has to do with the mechanism of sex and copulation in order to effectively transfer sperm from the mate to the female. The male has got to have parts which fit with female in terms of how the sperm can gets into the eggs. If that parts don't fit right, copulation are not going to be successful.
Mechanical isolation
Gametes, which are the eggs and sperms, can't fuse together.
Gametic isolation
It occurs after the zygote is formed, but it doesn't go much farther. Thus, the species still separate.
postzygotic isolating mechanism
1: hybrid inviability
2: hybrid sterility
3: hybrid breakdown
different type of postzygotic isolating mechanisms
It reduces a hybrid's capacity to mature into a healthy, which embryo died due to miscarriage or stillbirth.
hybrid inviability
The hybrid embryo is created. There is also development proceeds and actual baby born, but many cases the hybrid offspring can't reproduce next generation (not fertile) even though it's alive.
hybrid sterility
Some hybrid offspring can be fertile and reproduce next generations, but it doesn't get vary far and perpetuate a lineage into forever future.
hybrid breakdown
there's no substantial change over a long period of time.
stasis
Species has disappeared from earth and it's permanent.
Extinction
Environment changes:
1: there is too little variation to allow natural selection to lead to adaptation.
2: Natural selection takes time to occur. There is too fast for natural selection to lead adaptation.
There is 2 reason of extinction occurring
mass extinction are very substantial extinctions in a relatively short period of time.
mass extinction
Cretaceous period and Permian period
Example of mass extinction
Evolutionary change below the species level. There is evolution within species and allele frequency changes within a population across generation.
Microevolution
1: It tends to happen on relatively short time scale ( 1 - 1000's generation) then macroevolution.
2: Natural selection, gene flow, genetic drift, and nonrandom mating are main drivers.
The characteristic of Microevolution
Evolutionary change above the species level. It's changes that result in new taxonomic groups such as new class. family, or phylum etc.
Macroevolution
1: It tends to happen on relatively long time scale (1000 - millions generation) then microevolution.
2: There is appearance of major morphological or functional changes in the evolutionary record which is evolutionary novelty.
3: It includes adaptive radiation.
The characteristic of Macroevolution
Diversification of ancestral species into many descendant species that live in diverse habitats and make their living in diverse ways.
adaptive radiation
mutation and exaptation
2 rare process contributing to macroevolution (lead to macroevolution)
1: It's relatively rare
2: The estimated rate, sort of the normal expect rate of mutation 1/ million zygote per locus.
mutation
1: mutation that result in novel spatial organization of body plan.
2: mutation that result in novel development timeline.
2 types of mutations especially important to macroevolution
1: homeotic gens
2: Hox gene
mutation that result in novel spatial organization of body plan.
master regulatory genes that control the placement and spatial organization of body parts by producing protein products that regulate other genes in group of cells.
homeotic gene
It's homeotic genes that are found in animals. It provides positional information during development, including controlling development along anterior posterior, limb buds, and genital.
Hox gene
1: There's a mutation to the gene itself so that DNA changes and that gene was present in the ancestor which was changes significantly.
2: There's mutation that alter the expression of that gene. It's not really changing the gene from one gene into some different gene. But the mutation would affect how this gene is expressed.
2 sort of possible of mutation in homeotic gene
1: heterochrony
2: paedomorphosis
mutation that result in novel development timeline.
A change in the rate or timing of developmental event from the ancestral taxon to descendant taxon.
heterochrony
A type of heterochrony where the adults of the descendant taxon retained juvenile characteristics. They basically look like the juvenile of their ancestor.
paedomorphosis
It's structure that has evolved in an ancestral taxon for a particular function, than is co-opted for a novel function in descendent taxon.
exaptation
orderly sequence of cell division by mitosis after fertilization.
cleavage pattern
1: consist of 128 cells
2: hollow and fluid filed ball of cell
blastula
the fluid filled space inside blastula
blastocoel
radial cleavage and spiral cleavage
2 patterns of cleavage
the top of 4 cells are sitting directedly on top of bottom 4 cells.
radial cleavage
the top 4 cells are shifting a little bit relative to the bottom 4 cells
spiral cleavage
1: no germ layer
2: diploblastic
3: triploblastic
Embryonic germ layers
zygotes develop to the blastula stage, but stop there. There's no further folding or tweaking of the blastula ,so they don't have any true tissue.
no germ layer
Have 2 embryonic germ layers. When the blastula begins that transformation leading to gene layers that initially lead to condition of being diploblastic.
diploblastic
Have 3 embryonic germ layers. It's adding the mesoderm between ectoderm and endoderm.
triploblastic
Blastula becomes gastrula via gastrulation.
Formula of blastula to gastrula
the process to transform the blastula into gastrula
gastrulation
the next stage of blastula after gastrula.
gastrula
Fluid filled body cavity lined on all sides by mesoderm.
coelom
Have a true coelom
coelomate
no cavity
acoelomate
cavity lined on by one side (not true coelom)
pseudocoelomate
protostomes and deuterostomes
2 clades of animals
1: spiral determinate cleavage ( 2 cells stage)
2: blastopore to mouth
3: coelom formation: coelom form by schizocoely.
protostomes
Mesoderm forms as solid mass btw ectoderm and endoderm. Then cells die in middle by apoptosis which creating a cavity (coelom).
meaning of coelom form by enterocoely
Gastrula extends to top which form complete gut. Meanwhile, mesoderm fills with solid mass. Cells die in middle by apoptosis which creating a cavity.
Process of coelom form by schizocoely
1: radial determinate cleavage ( 4 cells stage)
2: blastopore to anus
3: coelom formation: coelom form by enteroceoly.
deuterostomes
Mesoderm bugled from endoderm and pinches off which creating a cavity surrounded my mesoderm.
Meaning of coelom form by enteroceoly
Gastrula extends to top which form complete gut. Meanwhile, mesoderm bugled from endoderm and pinches off which creating a cavity surrounded my mesoderm.
Process of coelom form by schizocoely
1: Conformer
2: Regulator
managing the internal environment
It allows internal environment to changes as the external environment changes.
Conformer
It controls internal environment to changes as the external environment changes.
Regulator
It refer to the maintenance of a constant internal state. (caused by regulator)
Homeostasis
1: sensor
2: control center
3: effector
homeostasis system component
Monitors current status of a given variable
sensor
Compares input to a normal set volume
control center
To change the variable
effector
Change occurs to counteract previous change.
Negative feedback system
Change causes more change in same direction
Positive feedback system
1: radiation
2: conduction
3: evaporation
4: convection
Heat formation
all object warmer than absolute zero emit electromagnetic waves. Heat is lost from object and gain heat from the sun.
radiation
Direction transform of heat btw objects that are directly content with each other.
conduction
The removal of heat as water evaporate. The water molecules go to gaseous stage.
evaporation
It's the heat transfer by the movement of water and oxygen pass the object.
convection
It has a variable body temp.
Heterotherm
It has a constant body temp.
Homeotherm
Animals have a relatively low metabolic rate, and primary source of heat is environment
ectotherm
Animals have a relatively high metabolic rate and generates many heat. Main source of heat is animals' metabolism.
endotherm
Cost: activity depends on ambient temp.
Benefit: requires little food for energy.
Cost and benefit of heterothermic ectotherm
Cost: require much more food
Benefit: active at all time
Cost and benefit of homeothermic endotherm
Changes in behavioral that influence body temp.
behavioral thermoregulation
The blood vessel gets narrower (conserve heat if too cold.)
vasoconstriction
The blood vessel gets wider (loss heat if overheated)
vasodiation
It's going to retain heat in the body and reduce heat loss to the environment.
Counter Current Heat Exchanger
1: Artery and vein aren't closed (not touching)
2: Heat loss in environment.
3: Energetic inefficient
Without CCHE
1: Artery and vein closed (touching)
2: Retain heat in core
3: Energetic efficient
4: temp gradient along entire length
With CCHE
piloerection and fat
Endotherm have plenty of insulation
Erection of hair standing / feather / fur that enhance the insulated factors.
piloerection
Hibernation and torpor
In some endotherms, a substantial decrease in metabolic rate and body temp occur to save energy and reduce food requirements at time when remaining endothermic would be too costly.
It's a stage of minimal activity and metabolic depression which is seasonal heterothermy characterized by low body-temp, slow breathing, heat-rate and metabolic rate. (long term weeks to months)
Hibernation
It's a state of decreases physiological activity in an animal which usually by reduced body temp and metabolic rate. (short term hours to days)
torpor
Composed of sensory and motor neurons
peripheral nervous system
Composed of interneuron of brain and spiral cord
central nervous system
sensory receptor, sensory neuron, interneuron of CNS, motor neuron, effector cells
basic pathway that information is sent through the nervous system
cells that accomplish some sort of jobs
effector cells
Neural circuit and bypasses brain
Reflex arc
Receive incoming information from whatever cell is communicating
Function of Dendrites
interface btw neuron and cell which communicate with another neuron which is effector cells.
synapse
insulates the axon and cause the electrical message to travel aster and more efficiently.
myelin sheath
The gap btw adjacent Schwann cells
node of Ranvier
To support cells which do other jobs to support nervous system. It also includes Schwann cells in PNS and oligodendrocytes cell in CNS.
Function of Glial cell
Form myelin sheath
Function of Schwann cells in PNS and oligodendrocytes cell in CNS
It controls skeletal muscles which would be a voluntary type of muscle and responds to external stimuli.
somatic nervous system
It controls internal environment which would be involuntary.
Automatic nervous system
It's voltage difference across membrane
Membrane potential
ungated channel and gated channel
Ion channel
nothing that blocks ions and always open
ungated channel
It alters membrane permeability.
gated channel
Voltage regulated channels and ligand regulatory channel
2 types of gated channel
open when particular molecule bind to receptor.
ligand regulatory channel
Neuron at rest about -70mV.
resting potential
when neuron is at rest, all gate channels are close, and there are more ungated K+ channel than Na+ channels. Sodium potassium pump to maintain resting potential at -70m which 2 K+ pump in and 3 Na+ pump out.
Establishing resting potential
When a stimulus is detected and stimulus is received, neuron respond to it initially. Its a local event on neuron membrane.
graded potential
local membrane potential become more polarized
hyperpolarization
local membrane potential become less polarized. Only depolarization bring neuron closer to generate on action potential.
depolarization
It's actual electrical event would result in a message being sent down the axon to the postsynaptic cell.
action potential
the magnitude of response is proportional to the magnitude of the stimulus.
meaning of graded
Graded potentials add together.
summation
1: they're local events on the axon membrane
2: there's property of being "all or none" event due to threshold potential about -55mV.
Characteristic of axon potential
1: open or close in response to a change in membrane potential.
2: It has many V-R K+ channel about 1gate per channel, either open/ close.
3: It also has V-R Na+ channel about each has 2 gates.
Voltage regulated channels
1. activation gate
2. inactivation gate
2 types of V-R Na+ channel
1: It's closed when the local membrane is at rest
2: It's open when there's in response to a little depolarization.
activation gate
1: It's closed in response to many of depolarization.
2: It's open when the neuron is at rest.
inactivation gate
Brief period time when the local spot on the membrane is unable to respond to another stimulus which starts from threshold potential to the end.
Refractory period
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