Lecture 7: Animal Phyla Part `1

Question 1

Animals are heterotrophs meaning?

Answer 1

they need to ingest their food unlike plants which are autotrophs

Question 2

Some other animal facts?

Answer 2

• heterotrophs
• multicellular
• no cell wall
• most animal reproduce sexually

Question 3

What is the origin of animals?

Answer 3

the hypothesis is that they evolved from a group of colonial protists called choanoflagellates
evidence is: colar cells preset in animal phyla but not in plants, dna is highly similar

Question 4

Animals share body plan characteristics that can be compared among groups, what are the 6 characteristics?

Answer 4

symmetry, tissues, body cavities, digestive cavities, development, skeleton

Question 5

What are the 3 types of symmetry?

Answer 5

1) asymmetry: not symmetrical like sponges
2) radial symmetry: does not have a right or left side like sea stars
3) bilateral symmetry: have right and left sides like humans

Question 6

What are tissues?

Answer 6

group of similar cells carrying out a main function: embryonic germ layers form as the embryo develops, become tissue and organs

Question 7

Ectoderm?

Answer 7

outer layer; forms outer covering and CNS

Question 8

Mesoderm?

Answer 8

middle layer; forms all other tissues/organs

Question 9

Endoderm?

Answer 9

inner layer; forms digestive tract/ cavity lining, organs like liver and lungs in vertebrates

Question 10

Whats a diploblastic animal?

Answer 10

has 2 layers including ectoderm and endoderm

Question 11

Whats a triploblastic animal?

Answer 11

has 3 layers including ectoderm, mesoderm, and endoderm; all bilateral animals triploblastic

Question 12

Body cavities?

Answer 12

fluid filled spaces between tissue layers during the early development of organisms: function in support, nutrient transport, and waste removal

Question 13

Whats coelom?

Answer 13

a fluid filled cavity surrounded by mesoderm:
- cushions and holds organs in place

Question 14

Acoelomate?

Answer 14

have no coelom to help the organism develop more complex internal organs: aka no body cavity surrounded by mesoderm

Question 15

Pseudocoelomate?

Answer 15

have a fake coelom; only partially surrounded by mesoderm therefore organs are held loosely in place

Question 16

Coelomates?

Answer 16

have a true coelom: complex organ systems can develop within their coelom: better reproduction, mobility,and communication

Question 17

Digestive cavities

Answer 17

• 1 way flow
• gastrovascular cavity: gut with one opening; food is ingested and waste is secreted from one opening ex: jellyfish
• alimentary cavity: gut with 2 openings: ex: dog

Question 18

Development protostome vs deuterostome

Answer 18

protosome: the mouth develops from the blastopore
deuterosome: the anus develops from the blastopore

Question 19

during embryonic development of animals with bilateral symmetry, the first opening produced is called the?

Answer 19

blastopore

Question 20

Skeleton?

Answer 20

a skeleton system functions for support, to protect internal organs, and allow for the movement

Question 21

what are the 3 types of skeleton designs?

Answer 21

endoskeleton, exoskeleton, and hydrostatic skeleton

Question 22

What is an endoskeleton?

Answer 22

skeleton that consists of hard mineralized structures located within the soft tissues of organisms; vertebrates

Question 23

What is an exoskeleton?

Answer 23

external skeleton that consists of hard encasement on surface of organism; crab or beetle

Question 24

What is a hydrostatic skeleton?

Answer 24

flexible skeleton supported by fluid pressure; earthworms, starfish

Question 25

Porifera/sponges?

Answer 25

suspension feeders- eat what pass through their cavity & live in aquatic habitats
1) asymmetric
2) no tissue or organ
3) no body cavity
4) no digestive cavity
5) n/a
6) hard spicules or soft spongin/endoskeleton

Question 26

Cnidaria?

Answer 26

examples: jellyfish, corals, hydra, anemones
live in aquatic habitats
1) radial symmetry
2) diploblastic
3) no body cavity
4) gastrovascular cavity
5) n/a
6) hydrostatic skeleton

Question 27

Platyhelminthes?

Answer 27

flatworms, tapeworm, planaeia
some are free living aquatic and some are parasitic
1) bilateral symmetry
2) triploblastic
3) compact coelom
4) gastrovascular cavity
5) protosome development
6) hydrostatic skeleton