Introduction to Animals

Animals are a diverse group of multicellular organisms that are capable of movement. They are part of the kingdom Animalia and are characterized by their ability to obtain energy by consuming other organisms. This sets them apart from plants, which produce their own food through photosynthesis.

Characteristics of Animals

• Multicellular: Animals are made up of more than one cell.
• Heterotrophic: They obtain energy by consuming other organisms.
• Movement: Most animals are capable of voluntary movement at some stage of their lives.
• Sexual Reproduction: Most animals reproduce sexually, although some may also reproduce asexually.

Classification of Animals

Animals are classified into different groups based on their characteristics. The main groups are:

• Vertebrates: Animals with a backbone, including mammals, birds, reptiles, amphibians, and fish.
• Invertebrates: Animals without a backbone, including insects, worms, mollusks, and more.

Study Guide

Here are some key points to remember when studying "Introduction to Animals":

1. What are the main characteristics of animals?
2. How are animals classified?
3. Give examples of vertebrates and invertebrates.
4. Explain the differences between heterotrophic and autotrophic organisms.
5. What are some examples of how animals obtain energy?