Body symmetry

Animal Body symmetry

1. The Animal Body Symmetry

2. Introduction Animal classification When classifying animals we look at some major characteristics. Vertebrae- this is a bone structure that supports and protects the spinal chord of animals. The spinal chord connects the brain to every nerve in the body. Invertebrates- are animals without a backbone. 97% of all animal species are invertebrates. These animals have other protective structures, like shells and exoskeletons.

3. Symmetry Arrangement of body parts around a central axis Asymmetrical - animals have no particular symmetry. Radial symmetry - means the animal is organized similar to a wheel. Any longitudinal cut will give off in an equal half. Bilateral symmetry - means the animal has definite right and left halves.  Types of Body Symmetry

4. Most animals are bilaterally symmetric , including humans. It could be divided into matching halves by drawing a line down the center. It permits streamlining, favors the formation of a central nerve center, contributes to cephalization, and promotes actively moving organisms.

5.   Radially symmetric animals are symmetrical about an axis extending from the center of the oral surface. Radial Symmetry Coral Jelly Fish

6. Asymmetrical Do not show definite symmetry.

7. Biradial symmetry I n addition to the anteroposterior axis, there are also two other axes or planes of symmetry at right angles to it and to each other.