Lesson 19 lecture notes

Question 1

about how many animal species are there in the world?

Answer 1

~8.7 million

Question 2

What are the four characteristics that all animals have in common?

Answer 2

1 Heterotrophic
2 Multicellular
3 no cell walls
4 some sort of skeletal structure

Question 3

About how many phyla of animals are there?

Answer 3

~30

Question 4

Endothermic animals’ body temperatures remain constant through what means?

Answer 4

metabolic functions or body coverings

Question 5

Ectothermic animals live in habitats with…

Answer 5

conditions that are fairly stable

Question 6

Animals with 1 germ layer have what kind of symmetry…

Answer 6

asymmetrical

Question 7

Animals with 2 germ layers have what kind of symmetry…

Answer 7

radial symmetry

Question 8

Animals with 3 germ layers have what kind of symmetry…

Answer 8

bilateral symmetry

Question 9

Symmetry begins

Answer 9

after fertilization, during cleavage

Question 10

The endoderm becomes…

Answer 10

the digestive tract

Question 11

The mesoderm becomes…

Answer 11

most other organs: heart, muscles, bones, lungs, etc.

Question 12

The ectoderm becomes…

Answer 12

outer components: skin, hair, nails/claws, etc.

Question 13

Sponges have no…

Answer 13

nervous systems
digestive systems
circulatory systems

Question 14

How do sponges eat?

Answer 14

Their collar cells pull water through the animal, digesting microorganisms

Question 15

Mesenchyme has either —– or —– floating in it

Answer 15

spicules or spongin

Question 16

What are collar cells?

Answer 16

They have a “collar” and flagella that extend out of the collar

Question 17

Mobile cells in sponges that move freely through the mesenchyme

Answer 17

amebocytes

Question 18

What do amebocytes do?

Answer 18

bring oxygen to the cells

create lime or silica

Question 19

Sponges are hermaphrodites, meaning…

Answer 19

they have both male and female parts