Identify the Body Symmetry, Segmentation, and Skeletal System of Major Animal Groups: Pig, Rat, Crayfish, Grasshopper, Annelida (Earthworm), Starfish, Squid, Clam, and Hydra

Pig:

• Body Symmetry: Bilateral symmetry.
• Segmentation: Not externally segmented, but has internal segmentation (e.g., regions like head, thorax, abdomen).
• Skeletal System: Endoskeleton made of bones.

Rat:

• Body Symmetry: Bilateral symmetry.
• Segmentation: Not visibly segmented but has segments internally.
• Skeletal System: Endoskeleton composed of a bony structure.

Crayfish:

• Body Symmetry: Bilateral symmetry.
• Segmentation: Exhibits clear segmentation (cephalothorax and abdomen).
• Skeletal System: Exoskeleton made of chitin.

Grasshopper:

• Body Symmetry: Bilateral symmetry.
• Segmentation: Clear segmentation within the thorax and abdomen.
• Skeletal System: Exoskeleton made of chitin.

Annelida (Earthworm):

• Body Symmetry: Bilateral symmetry.
• Segmentation: Well-defined segmentation throughout the body.
• Skeletal System: Hydrostatic skeleton, supported by coelomic fluid.

Starfish:

• Body Symmetry: Radial symmetry (usually pentamerous).
• Segmentation: Not segmented but has a structure divided into arms/rays.
• Skeletal System: Endoskeleton made of calcareous plates.

Squid:

• Body Symmetry: Bilateral symmetry.
• Segmentation: Not externally segmented, but has internal divisions.
• Skeletal System: Internal shell known as a pen, and muscular structure.

Clam:

• Body Symmetry: Bilateral symmetry.
• Segmentation: Not visibly segmented externally.
• Skeletal System: Shell composed of calcium carbonate, protects soft body.

Hydra:

• Body Symmetry: Radial symmetry.
• Segmentation: Not segmented.
• Skeletal System: Hydrostatic skeleton supported by water pressure.