Chapter 9 Flashcards

(20 cards)

1
Q

Asymmetry

A

the lack or absence of symmetry

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

Radial Symmetry

A

symmetry around a central axis, as in a starfish or tulip flower

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

Bilateral Symmetry

A

symmetrical arrangement of an organism or part of an organism along a central axis so an organism can be divided into two equal halves

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

Ectoderm

A

one of three primary germ layers. The ectoderm is the most exterior layer of skin

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

Endoderm

A

Innermost of the primary germ layers. Gives rise to the respiratory tract, gastrointestinal tract.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

Mesoderm

A

One of three primary germ layers. Middle layer giving rise to a number of structures including bone, muscle, connective tissue and middle layer of skin

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

Diploblastic

A

describing an animal with a body wall composed only of two layers, ectoderm and endoderm

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

Triploblastic

A

describing an animal having a body composed of three germ cell layers

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

Protostome

A

first opening in the embryo becomes the mouth. At this stage of development the later specialization of any given embryonic cell has already been determined.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

Radial Cleavage

A

cleavage that is typical of deuterostomes and that is characterized by arrangement of the blastomeres of each upper tier directly over those of the next lower tier resulting in radial symmetry

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

Spiral Cleavage

A

cleavage that is typical of protostomes and that is characterized by arrangement of the blastomeres of each upper tier over the cell junctions of the next lower tier

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

Deuterostome

A

distinguished from protostomes by their deuterostomic embryonic development. The first opening becomes the anus rather than the mouth

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

Coelom

A

fluid filled body cavity that is completely lined by tissue created from the mesoderm.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

Pseudocoelom

A

second body cavity which occupies a space between the mesoderm of the body wall and the endoderm of the gut

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

Acoelomate

A

an invertebrate lacking a coelom. such as flatworms and characterized by bilateral symmetry and a digestive cavity that is the only internal cavity

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

Lophotrochozoa

A

One of the two distinct clades within protostomes

17
Q

Ecdysozoa

A

Other major grouping of clades including Arthropoda, Nematoda etc

18
Q

Incomplete Gut

A

only have one opening for food intake and waste removal

19
Q

Complete Gut

A

clear beginning and end with separate openings for food and waste

20
Q

Metamerism

A

phenomenon of having a linear series of body segments fundamentally similar in structure. Each segment is called somites or metameres