animal evolution

Question 1

part 1: animal characteristics: multicellular, is there cell walls?
can they move

Answer 1

interconnected cells
gap junctions between cells= communication
tight junctions between cells= holds interconnected cells together

no cell walls

yes, can move (react). if cannot move then they were mobile some point in their life

Question 2

part 2: animal characteristics: heterotrophic, embryonic tissue, reproduction?

Answer 2

obtain energy by consuming energy and releasing food,

ectoderm= skin (outer), mesoderm= digestive system (middle), endoderm= internal organs (inside)

sexual

Question 3

evolution of multicellularity: which is the common ancestry of animals, how they live, what they have.
is it best outgroup?

clade of multicellular organisms

Answer 3

group of protists called choanoflagellates
live in colonies,

have flagella and a collar of microtubules

yes, for the animal clade

metazoa- closely associated w/ animal clade

Question 4

earliest descendent of animals

Answer 4

porifera (sponge)

Question 5

porifera/ phylum porifera:
basel group and body structure

Answer 5

sponges
simple body structure

Question 6

porifera/ phylum porifera: 2 cell layers

Answer 6

Epidermis
* Choanoderm:Draws in food particles (to collar cells)
* Passed it through amoebocytes to process food)

Question 7

middle region of porifera:
porocytes
osculum
mesohyl
amoebocytes

Answer 7

control the amount of water that enters pores into the spongocoel, and out through osculum (mouth)

maintains the tubular shape of sponge and structural support by hard spicules

help sponge eat, grow, reproduce

Question 8

what does it mean when sponge is totipotent

Answer 8

produce asexually by budding. can separate and grow/ combine with others to make new sponges, and can change cell fate (become another type of cell)

Question 9

evolution of radial symmetry
(evolved from? body axis? )

Answer 9

evolved from cnidaria phylum
no right or left side, only top and bottom

Question 10

no membrane=
membrane=
top and bottom

Answer 10

parazoa
eumetazoa
oral, aboral

Question 11

two major events early in development

Answer 11

cleavage- from mitotic division
gastrulation (forming of gastric cavity): making of mouth- blastropore, gut, etc.

Question 12

embryonic tissues: how many germ layers, and names

Answer 12

diploblastic (two germ layers)
ectoderm (outer layer of embryo)
endoderm: (inner layer (gut)

Question 13

phylum cnidaria (symmetry, germ layers, body shape, clade)

Answer 13

ex: jellyfish
radially symmetrical, diploblastic
clade= anthozoa (ex: corals)
primarily medusa stage but was polyp (they bud off making them become medusa)

Question 14

difference between diploblastic, and triploblastic

Answer 14

3 layers and have mesoderm (no more jelly- filled space)

Question 15

Grades of organization body cavities: (eu)caelomates

Answer 15

Cavity is completely lined with mesoderm
(If we dont have this we see everything inside)

Question 16

Grades of organization body cavities: pseudococlomates (hemocoel)

Answer 16

Body cavity partially lined by tissue derived from mesoderm

Question 17

Grades of organization body cavities: Acoelomates

Answer 17

some animals have curities that aren’t compietely . No Space between tissue luyers
Ex:flatwarms
cant get big since no room for circuatay system in order to diffuse nutrients

Question 18

Protostome vs deuterostome

Answer 18

Spiral and determinate cleavage (can take cell), coelem form solid masses, blastopore forms mouth

Radial and intermediate cleavage, coelem form folds of archenteron, blastopore forms anus, mesoderm forms coelem