final- part 1

Question 1

in what period did animals undergo diversification

Answer 1

paelazoic

Question 2

from what type of organism did multicellular animals most
likely evolve?

Answer 2

cyanobacteria- blue green sea bacteria

Question 3

list 4 key evolutionary branch points in the polygenetic tree of animals

Answer 3

presence or absence of tissues;body symmetry; coelom;embryonic development of true coelom

Question 4

What is a body cavity?

Answer 4

a fluid filled space in the body that holds and protects vital organs

Question 5

True tissues

Answer 5

ectoderm, mesoderm, endoderm

Question 6

body symmetry

Answer 6

radial and bilateral

Question 7

coelom

Answer 7

fluid-filled space separating digestive tract from the outer body wall=> led to complex animals

Question 8

embryonic developmental processes of true coelom

Answer 8

schizoceoly and enteroceoly

Question 9

what is phylum Porifera

Answer 9

sea sponge

Question 10

things to know abt phylum porifera

Answer 10

-mostly marine
-asymmetric and sessile
-reproduces asexually (fragmentation) and sexually (Hermaphroditism)
-lack of true tissue= cannot form organs
-filter feeders

Question 11

Poriferas specialized cells

Answer 11

Choanocyte
amoebocyte

Question 12

what are phylum Cnidaria

Answer 12

jellyfish, coral, hydraes

Question 13

things to know about phylum cnidaria

Answer 13

-mostly marine
-radial symmetry
-2 tissue layers= ecto and endoderm
-incomplete digestive tract/only has a stomach cavity
-sexual reproduction and asexual (budding)
-carnivorous with stinging cells or tentacles (cnidoblasts)

Question 14

terms to note

Answer 14

-outer layer of cell= ectoderm
-inner layer of cell= endoderm
-white space in the middle= hollow body cavity
-parthenogenesis = only female species

Question 15

what are phylum Platyhelminthes

Answer 15

flatworms, free-living flukes, and tapeworms

Question 16

things to know about platyhelminthes

Answer 16

-bilateral symmetry
-all environments and parasitic
-3 tissue layers and NO body cavity
-incomplete digestive system
- several organs including sexual and excretory

Question 17

Platyhelminthes have eye spots and oracles:

Answer 17

eye spots = photoreceptors that detect light
oracles = chemoreceptors

Question 18

Tapeworms

Answer 18

• have a scolex head that releases hooks into victim to hold them there
  -each section contains thousands of reproductive eggs so you must kill it at the head
  -the majority of the organism is the mesoderm

Question 19

What is phylum Nematoda

Answer 19

roundworms

Question 20

things to know about phylum Nematoda

Answer 20

-can live in all environments/ some are parasitic
-complete digestive system= more efficient at observing nutrients
-body cavity with psuedocoelom
-well-developed organs
-sexually reproduce hermaphroditic
- can rapidly reproduce w/ a very short lifespan
-Nematoda Ascaris= parasitic nematodes found in water and are found in pig and cow meat

Question 21

What is phylum Rotifera

Answer 21

microscopic sea organisms

Question 22

things to know about phylum Rotifera

Answer 22

• multicellular
  -freshwater
  -complete digestive system
  -body cavity/ psuedocoleom
  -parthenogenesis

Question 23

what are in phylum Mollusca

Answer 23

bivalves
snails
slugs
squids
octopi

Question 24

things to know about phylum Mollusca

Answer 24

live in all environments/ mostly aquatic

all have shell or secondary loss of shell

sexually reproduce

Eucoelomates

parts:
- visceral mass=organs/internal
-mantle= creates a shell
-foot= used for movements and catching food