Question

Write any three common characteristic features of the following phyla of invertebrates and classes of vertebrates.

Answer 1

1. Protozoa :

• Single-celled eukaryotes.
• Locomotion is done by pseudopodia.
• The nutrition is either autotrophic or heterotrophic.

2. Platyhelminthes:

• This Phylum includes flatworms.
• Excretion and osmoregulation occur through flame cells.
• These worms are hermaphrodites having both male and female reproductive organs in a single individual.

3. Mollusca:

• Soft-bodied animals without segmentation.
• The body is covered by a mantle and a shell.
• Respiration is carried through gills or lungs or both.

4. Class Reptilia:

• The body is covered by an exoskeleton of homy epidermal scales.
• The respiration is by lungs.
• The heart is three-chambered, except crocodile, which has four chambers.-

5. Class Mammalia:

• They have epidermal hairs, sweat, sebaceous and scent glands.
• The mammary glands are the modified integumentary glands.
• The external ear or pinna is present in most of the mammals.