Back to: ZOOLOGY 100 Level
How are you today? I’m really happy you’re here again, ready to learn something amazing. Have you ever wondered what makes animals different from plants, or even from each other? Today, we’re going to look at the general characteristics of animals. This is like learning the basic things that all animals have in common, whether it’s a lion in the savannah, a goat in your compound, or a fish swimming in a pond.
General characteristics
Multicellular Structure
One major thing all animals share is that they are made up of many cells. These cells work together in groups to perform specific jobs. Unlike some organisms like bacteria or amoeba (which are just one cell), animals have millions—even trillions—of cells that help them grow, move, and survive.
Heterotrophic Nutrition
Animals do not make their own food like plants do. Instead, they must eat other organisms—plants or other animals—to survive. That’s why animals are called heterotrophs. Whether it’s a cow grazing on grass or a lion hunting antelope, animals depend on food from outside sources.
Movement (Locomotion)
Most animals can move from one place to another, either to find food, escape danger, or search for mates. This movement is called locomotion. Even animals that appear slow, like snails or tortoises, still move. Some animals, like sponges, may be fixed in one place, but their young ones can move.
Reproduction
All animals have the ability to reproduce. This means they can give birth to or produce new animals of their kind. Some lay eggs (like chickens), while others give birth to live young ones (like goats or humans). Reproduction helps in the survival and continuation of their species.
Respiration
Animals must breathe to get energy. They take in oxygen and release carbon dioxide. The way they breathe may differ—humans use lungs, fish use gills, and insects use tiny holes in their bodies called spiracles—but all animals carry out respiration to stay alive.
Growth and Development
Every animal starts small and grows over time. This growth includes changes in size and sometimes in form. For example, a chick grows into a chicken, and a tadpole grows into a frog. Along with growth, animals also repair worn-out parts of their bodies.
Responding to Stimuli (Sensitivity)
Animals respond to what’s happening around them. If you touch a hot pot, you quickly pull your hand away. That’s your body responding to a stimulus. Animals use their sense organs to see, smell, hear, taste, and feel their environment.
Summary
- Animals are made of many cells (multicellular).
- They cannot make their own food—they are heterotrophs.
- Most animals move to find food, mates, or escape danger.
- Animals reproduce to produce young ones.
- They breathe to get energy through respiration.
- Animals grow and develop over time.
- They respond to changes around them using their senses.
Evaluation
- What does it mean when we say animals are heterotrophic?
- Mention two ways animals reproduce.
- How do fish and humans breathe differently?
- Why is it important for animals to respond to stimuli?
This journey you’re on is so powerful, and you’re making fantastic progress. Keep your curiosity strong and your love for learning alive. Afrilearn is here cheering you on, every single step of the way. Let’s keep moving forward—you’ve got this!