Chapter 32- Overview of Animal Diversity Flashcards Preview

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Flashcards in Chapter 32- Overview of Animal Diversity Deck (31):
1

What are the 5 key transitions in animal evolution?

1.) Tissues
2.) Symmetry
3.) Body Cavity
4.) Development
5.) Segmentation

2

Define Tissues

Closesly associated, similar or identical cells that work together to perform one or more functions

3

Define Organs

Discrete body part composed of several tissue types that performs one or more functions

4

Organ system?

Several organs that work together to perform one or more functions (circulatory system)

5

What are the two types of animals as defined by tissues

Parazoa-sponges, lack defined tissues and organs
Eumatozoa-all other animals

6

What are the two main types of symmetry in animals?

Radial symmetry
Bilateral symmetry

7

What is Radial Symmetry

Body parts arranged around central axis
-Can be bisected into two equal halve in any 2d plane

8

Bilateral Symmetry

Body has right and left halves that are mirror images; adaptation for motile life

9

What are the 2 advantages bilateral animals have over the radially symmetrical ones

Cephalization
Greater mobility

10

What is cephalization

evolution of a definite brain area; contains most sensory apparatus

11

What is the ectoderm

The outer germ layer-body coverings and nervous system

12

What is the mesoderm

The middle germ layer; skeleton and muscles and many internal organs

13

What is the endoderm

the inner germ layer; The digestive organs and intestines

14

What is the order of germ layers during embryonic development

Ectoderm (outer)
Mesoderm (middle)
Endoderm (inner)

15

What is the coelem

The body cavity; space between the endoderm and mesoderm

16

What are the 3 basic kinds of body plans

Acoelomates
Pseudocoelomates
Coelomates

17

What are acoelomates

no body cavity

18

What are pseudocoelomates

body cavity between mesoderm and endoderm

19

What are coelomates

Body cavity entirely within the mesoderm

20

What is an Open Circulatory system

blood passes from vessels into sinuses, mixes with body fluids, and reenters the vessels

21

What is a closed circulatory system

blood moves continuously through vessels that are separated from body fluids

22

What is the Blastula

Mitotic cell divisions of the egg form a hollow ball of cells: the blastula

23

What is the Blastopore

The blastula indents to form a 2 layer thick ball with an opening to the outside

24

What is the archenteron

formed from the blastula, it is a primitive digestive tract

25

What are Protostomes

They develop the mouth first from or near the blastopore
-anus develops either from blastopore or another region of embryo

26

What are Deuterostomes

develop the anus first form the blastopore
-mouth develops later from another region of the embryo

27

Cleavage pattern of embryological features

Protostomes= spiral cleavage
Deuterostomes=radial cleavage

28

Development fate of cells in bilaterians

Protostomes: determinate development
Deuterostomes: indeterminate development

29

Origination of Coelom in Bilaterians

Protostomes= Forms simply and directly from the mesoderm
deuterostomes=forms indirectly from the archenteron

30

Which (protostome or deuterostomes) are more evolutionary recent?

Deuterostomes; evolved from protostomes

31

What are the 2 advantage of segmentation

1.) allows redundant organ system in adults such as occurs in the annelids
2.) allows for more efficient and flexible movement because each segment can move independently