Zoology Quiz #2

RCA of all living things was around ____ years ago

3.5 bya

the first animal was estimated to have come about around ___ years ago

700 mya

5 traits of animals

multicellular Eukaryote, heterotrophic, sexually reproduce, mobile in at least one stage of life, and have tissues

tissues are derived from…

embryonic tissue layers

two tissues that are unique to animals

muscle and nerve

tissues =

specialized cells that function together

one animal that exists without true tissue =

sponge

the first tissue that we see evolutionarily is in ______ and is called ____

cnidarians, diploblastic

two ways to describe animals by tissue number

diploblastic or triploblastic

three layers that triploblasts have

ectoderm, endoderm, and mesoderm

ectoderm

outer covering of animal

endoderm

mos inner layer that gives rise to digestive tract

mesoderm

middle layer that gives rise to muscle and organs

in development, once the 2 gametes have made the zygote, what happens to make the blastocyst?

cell division while keeping volume same

blastocyst

hollow ball with cells on outside

what is the inside of the blastocyst called?

blastocoel

once blastocyst is made, what next?

gastrulation occurs to make the blastopore

gastrulation

ball pinches inward to make a opening, called the blastopore

the blastopore allows for what to rise?

archenteron

3 ways that triploblast tissue is arranged

acoelomate, coelomate, and pseudocoelomate

acoelomate

fully tissue with no gaps in mesoderm

coelomate

mesoderm has cavities

coelom = ___ ___ ____

true body cavity

pseudocoelomate

mesoderm does not fully fill out, leaves a pseudocoelom

muscles are a ____ of ____ ____

bundles of muscle fiber

1 muscle fiber =

1 cell with multiple nuclei

why do muscle fibers have multiple nuclei?

the stem cells that fused into it retained all nuclei

muscle fibers have 1 ___ ___

plasma membrane

muscle fibers are filled with ______

myofilaments

sarcomere

part of muscle cell that contracts

sarcomere is made of ___ and ___

myosin and actin

myosin is ___ and actin is _____(description words)

thick, thin

when relaxed the sacomere is ______

spread out

during contraction the myosin does what

push away from each other

during contraction the actin does what

pull together

before contraction the myosin filament has ___ ___

low energy

to increase energy in the myosin filament what happens?

break ATP apart while it is connected to myosin

once myosin has enough energy, what does it do>

bind to binding site on actin

after binding to actin, what happens?

loses ADP and P, decreases energy, and lets go of actin and causes motion

what does tropomyosin do in contraction?

blocks binding sites on actin to stop motion

what does troponin do?

moves tropomyosin out of binding sites to allow for contraction

3 muscle types

smooth, skeletal, cardiac

smooth and cardiac muscles are all ____

involuntary

involuntary means that…

we do not have to actively think about to do them

smooth muscle movement is

slow

smooth muscles are in…

digestive tract, vessels, urinary tract

skeletal muscles do ___ movement

voluntary

skeletal muscle is attached to…

skeleton

cardiac muscles are only in…

the heart

antagonistic pairs are in ___ muscles

skeletal

antagonistic pair muscles

two muscles work to do something, one contracts and the other relaxes to make the movement

neuron cell parts(3)

nucleus, dendrites, axon

axon does what

connects neuron to other neurons and sends signal

dendrites do what

receive signals

resting potential

electrical charge difference across cell membrane when at rest

how is the resting potential formed?

sodium pumps take out 3 Na ions and potassium pumps bring 2 K ions in

at rest, what are the gated ion channels doing?

nothing they are closed

depolarization does what in neurons

stimulant opens some channels and lets Na ion into cell

what happens after the initial Na channels are opened?

once a threshold of depolarization is reached, more Na channels open

before depolarization threshold was hit, what was the charge inside and outside the p.m

inside was negative and outside was positive

after depolarization threshold was hit, what is the charge inside and outside the p.m.

inside is positive and outside is negative

after threshold is passed and more channels are opened, waht happens?

Na channels close and K channels open

once the Na channels close and K channles open, what are the charges?

outside is positive and inside is negative

once the action potential process is done in one neuron it is spread to other neurons by the ___

axon

neurons are connected at the ___

synapse

presynaptic cell

neuron that already has action potential

postsynaptic cell

going to receive signal

synaptic cleft

area in synapse with Ca ions

to spread the signal, what happens after it travels down the axon?

presynaptic cell opens voltage gated channels and Ca ions flow in

after the Ca ions flow into the presynaptic cell, what happens?

vesicles with neurotransmitters fuse to presynaptic membrane and release neurotransmitters into cleft

once neurotransmitters are in the cleft, what happens?

bind to ligand gated channels and trigger action potential in other cells

metazoa node

node where most animals share rca

evidence shows that animals arose…

700 mya

frist fossilized animal was found

560 mya

Ediacaran era is when ___ of animal taxa happened

diversification

edicaran era was ___ to ___ mya

635, 541

Cambrian explosion was ___ to __ mya

535, 525

evidence of most animal phyla is in the Cambrian explosion exept for

invertebrates

why did the explosion likely occur?

predator prey interaction

which clade evolved during explosion

Bilateria

Bilateria clade has ___ ____

bilateral symmetry in embryonic stage

other factors that could have caused explosion

increase of oxygen and evo of HOX genes

HOX genes are related to

development

Difference ebtween Porifera and Cnidaria vs Bilateria

Bilateria is a group of multiple phylums while porifer and cnidaria are phylums themselves

phylum porifer general name

sponges

phylum porifera has no ___ ___

true tissue

p. porifera has no true organs just….

specialized cells

p.porifera/sponge is ___ in larva stage and ___ in adult stage

mobile, sessile

sessile

does not move

sponges are __ feeders

filter

sponges are what kind of symmetry

asymmetrical

sponges have two layers of cells

epidermal and inner layer of choanocyte/collar cells

pores of sponge are called

ostium

process of feeding through ostium

water enters ostium bringing food

area in sponge where water flows out

osculum

sponges also have another kind of cell

amoebocytes

what do amoebocytes do? in what animal?

collect food from choanocyte and spread to other cells in sponge

the oscula has ___ surface are than ostium

less

oscula having less surface area than ostium causes…

water to shoot out of sponge