Asymmetrical

Definition

Asymmetrical organisms lack symmetry, meaning they do not have a balanced arrangement of body parts. This is in contrast to symmetrical organisms that can be divided into mirror-image halves.

5 Must Know Facts For Your Next Test

1. Asymmetry is often found in simpler organisms, such as sponges.
2. Asymmetrical animals do not have a definite shape or form.
3. Asymmetry can be an adaptation to specific environmental conditions.
4. Most asymmetrical animals are sessile, meaning they are fixed in one place.
5. Unlike bilaterally or radially symmetrical animals, asymmetrical animals lack organized tissues and organs.

Review Questions

• What type of symmetry do sponges typically exhibit?
• How does the body structure of asymmetrical animals differ from those with bilateral or radial symmetry?
• Why might an organism develop an asymmetrical body plan?

Related terms

BilateralSymmetry: Bilateral symmetry refers to organisms with left and right halves that are mirror images.

RadialSymmetry: Radial symmetry describes organisms that can be divided into similar halves by multiple planes passing through the central axis.

Sessile: Sessile refers to organisms that are fixed in one place and do not move.