Evolution of Animals = ?

Group =

Likely ancestor =

# animal phyla =

metazoa

monophyletic

colonial flagellated protist

~35

Animal Characteristics

___cellular ____________

must consume ?

no ____; lots of _____ _____ with _____ supports cells

cells connected by ?

usually... (4)

multicellular heterotroph

must consume organic molecules

no cell walls; lots of extracellular matrix with fibers supports cells

cells connected by gap junctions

nerves, muscles, able to move, sexual reproduction

Classify using anatomical/developmental features (5)

1. presence or absence of tissues
2. type of body symmetry
3. numbr of enbryonic cell layers
4. presence or absence of a true body cavity
5. patterns of embryonic development

TISSUES

parazoa

eumetazoa

true/false: all animals have tissues

parazoa: no specialized tissues or organs

eumetazoa: >1 type of tissues; usually organs

FALSE: not all, but most do

SYMMETRY

2 types with examples

1. radially symmetrical with oral and aboral surfaces-- radiata

2. bilaterally symmetrical with cephalization and dorsal/ventral surfaces-- bilateria

cephalization

organs are concentrated in one side of the body

true/false: humans are bilateria

TRUE!!!

NUMBER OF EMBRYONIC (GERM) CELL LAYERS

a. radial animals

b. bilateral animals

a. radial animals: 2 embryonic cell layers (diploblastic)

    endoderm

    ectoderm

b. bilateral animals: 3 germ layers (triploblastic)

    mesoderm

    endoderm

    ectoderm

ectoderm

outer layer

endoderm

inner layer

mesoderm

is what?

develops when?

forms what?

middle layer

develops during gastrulation

forms muscles and most other organs

gastrulation

formation of the gut

BODY CAVITY (COELOM) TYPE

coelom cushions ?

can function as a ?

3 kinds

develops how?

coelom cushions organs

can function as a skeleton

3 kinds: acoelomates, pseudocoelomates, coelomates

develops: schizocoelous and enterocoelous

acoelomates

no body cavity

pseudocoelomates

body cavity, but it isn't lined with mesoderm

coelomates

"true coelom" is completely lined with mesoderm

only in triploblasts

schizocoelous development

a solid mass of mesoderm splits to form coelom

enterocoelous development

mesoderm buds off from gut to form coelom

EMBRYONIC DEVELOPMENT

2 kinds and examples

1. spiral cell cleavage-- protostomes

2. radial cell cleavage-- dueterostomes

spiral cell cleavage

what kind of cleavage?

blastopore becomes ?

what kind of development?

determinate cleavage: cell fate determined early

blastopore becomes mouth

schizocoelous coelom development

radial cell cleavage

what kind of cleavage?

blastopore becomes ?

what kind of development?

indeterminate cleavage-- cells stay pluripotent much longer

blastopore becomes anus

enterocoelous coelom development

**can perform in vitro fertilization**

Classification Characteristics

2 kinds

1. presence/absence of:

   -exoskeleton

   -notochord and/or vertebral column

   -metamerism

2. segmentation

metamerism

segmentation

both sponges and angiosperms

A. are multicellular

B. have organs

C. are radially symmetrical

D. are heterotrophic

E. more than 1 A-D are correct

A

C (not always)

animals that show determinant cleavage dont typically have identical twins because

A. cell fate is determined late in development

B. cell fate is determined early in development

C. these animals only reproduce asexually

D. these animals only can support 1 offspring

E. more than 1 A-D are correct

B

parazoa--porifera

how many species?

reproduce?

motion?

sponges

8000 species

reproduce sexually and asexually

free swimming larvae, sessile adults

radiata: cnidaria

symmetry?

# species?

___blastic

_________ cavity

incomplete _____

specialized _____ (2 examples)

2 body forms?

radial symmetry

~9000 species

diploblastic

gastrovascular cavity

incomplete gut

specialized tissues:

-muscles (not mesodermal)

-nerves (no brain)

body forms: medusa and polyp

radiata: ctenophora

 # species?

# rows of surface cilia (combs) for ______

# long tentacles

first complete ________

____blastic

~100 species, all marine

8 rows of surface cilia for swimming

2 long tentacles

first complete gut: seperate mouth and anus

diploblastic

most animals are ______ symmetrical

most animals are bilaterally

bilateria

___blastic

usually have a complete ?

often have a ?

2 major groups

one group contains: (2)

triploblastic

usually have a complete gut

often have a brain

2 major groups: protostomia and deuterstomia

protostomes contain lophotrochozoans and ecdysozoans

lophotrochozoans

usually either have ____ or ____

3 main groups

have either lophophore or trochophore larvae

3 groups: platyhelminthes, mollusca, annelida

lophophore

crown of tentacles

phylum platyhelminthes

aka ?

# of species

respire by ?

no _____ or ______ system

_____ symmetrical

has a _____

body cavity?

flatworms

20,000 species

respire by diffusion

no circulatory or respiratory system

bilaterally symmetrical

head

acoelomate

phylum mollusca

# of species?

____ body, maybe a _____ _____ ______

3 body parts?

circulatory system type

larvae type

>10,000 species

soft body, maybe a protective external shell

3 body parts: foot, visceral mass, mantle

open circulatory system

trocophore larvae

**look at figure 33.11**

annelida

# species?

body is ?

___-_____ ______ acts as a hydrostatic skeleton

circulatory system?

digestive system?

15,000 species

body is segmented

fluid-filled coelom acts as a hydrostatic skeleton

usually closed circulatory system

digestive system complete, unsegmented

ecdysozoans

named for ?

what is required for growth?

# groups; (name the main 2)

named for ecdysis

ecdysis of cuticle required for growth

8 groups; main 2 are nematodes and arthropods

nematoda

aka ?

# species

what covers body?

what acts as hydrostatic skeleton and ____ system?

lots of ____ species

aka roundworms

20,000 species (probably lots more)

cuticle of collagen covers body

pseudocoelom acts as hydrostatic skeleton and circulatory system

lots of parasitic species

arthropoda

# species

exoskeleton of ? (2)

jointed ?

body is ?

brain = ? ; eyes = ? ; nerves = ?

circulatory system?

>1 million species

exoskeleton of chitin and protein

jointed appendages

body is segmented

big brains; compound eyes; ventral nerve ganglia

open circulatory system

chitin

a glucose polymer

arachnids

3 major classes

crustacea, insecta, arachnida

insecta

# species?

# orders?

what underline the species diversity in insects? (2)

insect diversity linked to ?

more species than all other animals

35 orders

differences in wings and mouthparts underline the species diversity in insects

insect diversity linked to angiosperms

echinodermata

symmetry in larvae?

symmetry in adults?

no ______; simple _____ system

_____skeleton

vascular system? feet?

bilaterally symmetrical larvae

adults have modified radial symmetry

no cephalization; simple nervous system

endoskeleton

water vascular system with tube feet

chordata

4 innovations

1. notochord- single flexible supporting rod of tissue
2. dorsal hollow nerve chord
3. pharyngeal slits
4. postanal tail

vertebrates

subphylum of ?

____ column

endoskeleton of ____ or _____

often # pairs of appendages

subphylum of chordates

vertebral column

endoskeleton of cartilage or bone

often two pairs of appendages

which of the following are true?

A. all animals are organisms

B. all organisms are animals

C. the term organism and animal are synonymous

D. answers B and C are correct

E. none of A-D are correct

A

ALL ANIMAL CELLS

associate with?

contain?

sits in ?

exchange materials with ?

maintain ?

Associate with other cells

Contain water (in their intracellular fluid)

Sit in an extracellular fluid environment

Exchange materials with their environment

Maintain homeostasis – internal environment

What animal does not have tissues?

parazoa

4 most common tissue types in animals

1. muscle
2. nervous
3. epithelial
4. connective

what type of tissue has cells that specialized to contract and generate force?

what are the 3 types?

muscle tissue

skeletal, smooth, cardiac

SKELETAL

cells? found where?

nuclei where?

cells attach where?

under _____ control

form how? causes them to have more than one ____

big, long multinucleate cells found in x-section

nuclei at cell periphery

cells attach to bone, skin or exoskeleton

under voluntary control

skeletal muscle cells form by fusion of amniotic cells which is why they have more than one nucleus

SMOOTH

cell shape and location

nucleus

surround ?

_____ control

spindle-shaped cells, round in x-section

one nucleus per cell, in center of cell

surround hollow tubes and cavities

involuntary control (ex. intestines, stomach)

CARDIAC

cell size?

nucleus?

cell shape?

smaller cells

single nucleus

squared off ends (not spindle shaped)

nervous tissue initiates and conducts ?

distance and speed?

cell size?

nervous tissue initiates and conducts electrical signals

short or long distance, relatively rapid cell communication

cell size ranges from μm to m

epithelial tissue

aka ?

3 jobs?

sheets of ____ ____ that ____ ____

cell shape reflects?

cheek cells

protect, secrete, absorb

sheets of packed cells that line surfaces

epithelial cell shape reflects its job

connective tissues

3 jobs

5 major types

lots of ? ; few ?

connect, anchor, support

blood, adipose, blone cartilage, loose CT, dense CT

lots of extracellular matrix, few cells

**cartilage

organs are composed of...

example

two or more types of tissues

stomach

passive diffusion

across a plasma membrane

no transport protein or ATP required

facilitated diffusion

transport protein (no ATP)

active transport

use ATP and a transport protein to move molecules against a concentration gradient

insect and mammal respiratory systems

thickness?

tubes connect ?

____ diffuses across thin cells with ____ ____ ____

1 cell thick respiratory surface

tubes connect respiratory surface with environment

gas diffuses across thin cells with high surface area

what maximizes surface area for exchange or production?

example

folds

mitochondria

all animal cells maintain ?

do so by (2)

all animal cells maintian homeostasis

do so by:

conforming to environment

regulating itself at a constant, stable level, independent of the environment

animals can vary their

regulation

animals have control mechanisms (3)

sensor

integrator

effector

sensor

monitors particular variable

integrator

compares sensor signals to a baseline set point

effector

compensates for deviations between actual value and set point

control mechanisms may respond by negative or positive feedback

negative: (with example)

positive:

negative: reponses in a system move variable in opposite direction

example: shivering in response to cold raises body temp

positive: accelerates a process; much less common

paracrine signaling

cells release a signal that acts on nearby cells

endocrine signaling

cells release a signal that acts on distant cells

plasma membranes are:

A. completely impermeable to water

B. completely permeable to water

C. semipermeable to water

C

you place a red blood cell into an isotonic solution and wait for 10 minutes. the cell will:

A. stay the same

B. crenate

C. lyse

A

rate

amount

time

metabolic rate

rate of fuel use to supply ATP for metabolism

byproduct of molecule breakdown and ATP synthesis ?

heat

basal metabolic rate (BMR)

Amount of energy used at rest, standard temperature, not digesting food (postabsorptive state)

direct calorimetry measures ?

heat production

indirect calorimetry measures

O₂ consumption (misses anaerobic metabolism)

factors affecting metabolic rate

activity rate

digestion

amount of skeletal muscle vs fat making up body mass

developmental stage

growth

mass-specific BMR

mass-specific BMR decreases with increased ?

            BMR           

gram body weight

mass-specific BMR decreases with increased body mass

torpor

lower body temperature significantly every night

hibernation

lower body temperature for an extended period

animals are limited to a narrow temperature range because temperature affects... (3)

chemical reaction rate

protein structure

membrane fluidity

endotherms

retain ?

typically high ?

retain their own metabolic heat

typically high BMRs

ectotherms

body temp changes with

low ?

body temperature changes with environment temperature

typically low BMRs

homeotherms

body temperature is approximately stable

heterotherms

body temperature is quite variable

most birds and mammals are... (2)

endothermic and homeothermic

most other verts are

ectothermic and heterothermic

what makes endothermy though?

water's high specific heat

rete

bundles of parallel, countercurrent arteries and veins

nervous system

what is it?

send and receive?

composed of?

The body’s fast communication system

Send and receive electrical and chemical signals

Composed of glia and neurons

Glial Cells

_____ cells of different types

wrap around ____

support neurons...(3)

non-neural cells of different types

wrap around axons

support neurons during development, metabolically, for signal transduction

Neurons

made up of...(3)

cell body

dendrites

axon

-axon hillock

-axon terminal branches

cell body (soma)

contains nucleus and organelles

dendrites

plasma membrane (PM) extensions (single or branching) that receive incoming signals

axon

cell extension that sends signals

axon hillock

where the axon connects to the soma

axon terminal branches (nerve terminal)

at far end of axon

resting potential

definition

RP of neuron?

determined by?

cell has +/- charge relative to the outside environment

charge difference across the plasma membrane

RP of neuron is about -70mV

determined by ion distribution on inner and outer surface of PM

cell has - charge relative to the outside environment

RP is +/- because of...

cytosol side?

extracellular side?

RP is - because of concentration differences in some ions and proteins

cytosol side: lots of K, some Na, lots of - charged proteins

extracellular side: lots of Na, lots of Cl

RP regulated by...

lots of open __ ______ make PM leaky to __

some open __ ______ let __ into cytosol

Na/K pump...

RP regulated by membrane channels/transporters

lots of open K channels make PM leaky to K

some open Na channels let Na into cytosol

Na/K pump: active transport of 3 Na out and 2 K in

excitable cells

all cells have a ?

_____ and _____ are excitable; can rapidly change their membrane _____ using ____ _____ _____

electrical signal is a current generated by ____ _____

all cells have a RP

neurons and muscles are excitable; can rapidly change their membrane polarization using gated ion channels

electrical signal is a current generated by ion movements

2 types of gated ion channels (IC) in membrane

voltage-gated IC

ligand-gated IC

voltage-gated IC use _____ signal

voltage-gated IC use voltage signal

ligand-gated IC use _____ signal

ligand-gated IC use chemical signal

depolarization

becomes less -

hyperpolarization

becomes more -

small stimulus (above/below threshold)

stimulates a _____, _____ _____

below threshold

stimulates a local, graded response

big stimulus (above/below threshold)

stimulates an _____ _____ _____ _____ that is sent _____ _____

above threshold

stimulates an "all-or-none" response that is sent long-distance

action potentials (AP)

large-amplitude _____ (to ___mV) when _____ _____ is reached

caused by changes in membrane permeability to __ & __

______________ response

actively propagated _____ ______

large-amplitude depolarization (to +40) when threshold potential is reached

caused by changes in membrane permeability to Na & K

all-or-none response

actively propagated long-distance

Main events in AP

evolution of __ channels with slower opening time than __ channels

if both opened at the same time...

evolution of K channels with slower opening time than Na channels

if both opened at the same time, they would cancel each other out

Phospholipid bilayers are ___________ to ions

A. very permeable

B. slightly permeable

B. slightly permeable

Why are phospholipid bilayers relatively impermeable to ions?

A. ion are small

B. ions are charged

C. ions are uncommon in the cytosol or extracellular environment

D. more than 1 of A-C are correct

B. ions are charged

refractory period

while __ __ channel is inactivated

that patch of membrane won't...

limits on action potential _____

ensures _____ (and the _____ _____) propagates down the _____ (not back to _____ _____)

while VG K channel is inactivated

that patch of membrane won't respond to other stimuli

limits on action potential frequency

ensures depolarization (and the action potential) propagates down the axon (not back to cell body)

AP begins at _____ _____ because few _____ _____ __ channels in cell body, lots in axon

AP begins at axon hillock because few voltage gated Na⁺ channels in cell body, lots in axon

signal speed varies

bigger _____ = lower _____ + faster _____

myelinated/unmyelinated faster than myelinated/unmyelinated

bigger axons = lower resistance + faster signal

myelinated faster than unmyelinated

myelination not _____ - gaps at nodes of _____

myelination not cuntinuous - gaps at nodes of Ranvier

saltatory conduction

AP jumps to next node

synapses

2 kinds?

at axon terminal brances, neuron synapses with a 2^nd neuron, or a muscle or gland cell

electrical and chemical

electrical synapse

signal propagated through gap junctions that link cells

chemical synapse

neurotransmitter released from presynaptic cell signals to postsynaptic cell

structure and function of a chemical synapse (4 steps)

1. AP opens voltage gated Ca²⁺ channels in presynaptic nerve terminal; Ca²⁺ diffuses in
2. Increased intracellular Ca²⁺ causes vesicle exocytosis; neurotransmitter enters synaptic cleft
3. Neurotransmitter diffuses across cleft; binds to ligand gated ion channels/receptors in postsynaptic cell membrane
4. postsynaptic cell membrane depolarizes

effects of binding of neurotransmitter (2)

excite = local depolarization

inhibit = local hyperpolarization

synaptic signal ends when neurotransmitter disassociates from _____ _____

synaptic signal ends when neurotransmitter disassociates from postsynaptic receptor

neurotransmitter

more than ___ different kinds in animals

categorized by _____ or _____ _____

response of post-synaptic cell depends on _____ _____

same neurotransmitter can _____ 1 cell and _____ another

more than 100 different kinds in animals

categorized by size or molecular structure

response of post-synaptic cell depends on receptor type

same neurotransmitter can excite 1 cell and inhibit another

synaptic integration or summation

likelihood of summation depends on _____ _____

input from synapses close together or close to axon hillock are more likely to be _____

many events at 1 time sum; may each threshold potential

likelihood of summation depends on threshold potential

input from synapses close together or close to axon hillock are more likely to be integrated