Definitions

Question 1

Acoelomate

Answer 1

Animals that lack an internal body cavity

Question 2

Coelomate

Answer 2

Animals that contain an internal body cavity

Question 3

Coelom

Answer 3

A fluid filled body cavity that supports organs

Question 4

Segmentation

Answer 4

The division of the body into repetitive sections

Question 5

Cephalization

Answer 5

An evolutionary trend where nervous tissue becomes concentrated toward the anterior end of an organism

Question 6

Mesoderm

Answer 6

The middle layer of cells found in most animals. In humans this layer produces muscles, blood, kidneys and reproductive organs.

Question 7

Endoderm

Answer 7

The inner layer of cells found in most animals. In humans this layer produces lung, liver, pancreas and bladder

Question 8

Ectoderm

Answer 8

The outer layer of cells found in most animals. In humans this layer produces skin, nerve tissue, and sense organs

Question 9

Polyp

Answer 9

A sessile body form of a cnidarian characterized by a cylindrical shape with tentacles extending upwards and outwards.

Question 10

Medusa

Answer 10

A motile body form of a cnidarian characterized by flattened form that has the mouth at the bottom with tentacles extending below the mouth

Question 11

Asymmetrical

Answer 11

Having an irregular body shape

Question 12

Radial Symmetry

Answer 12

A body plan that can be divided along several planes to produce 2 identical halves

Question 13

Bilateral symmetry

Answer 13

A body plan that can be divided along one plane to produce 2 identical halves