Five Kingdoms of Life

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Every living creature on Earth belongs to a kingdom. Scientists debate how many kingdoms there are, but many agree there are five. Here is how the five kingdoms are organized. Or, see how some other scientists categorize life into sixkingdoms.

Monera

Monera are single-celled organisms that don’t have a nucleus. Bacteria make up the entire kingdom. There are more forms of bacteria than any other organism on Earth. Some bacteria are beneficial to us, such as the ones found in yogurt. Others can cause us to get sick.

Protists

Protists are mostly single-celled organisms that have a nucleus. They usually live in water. Some protists move around, while others stay in one place. Examples of protists include some algae, paramecium, and amoeba.

Fungi

Fungi are usually motionless organisms that absorb nutrients for survival. They include mushrooms, molds, and yeasts.

Plants

Plants contain chlorophyll, a green pigment necessary for photosynthesis, a process in which plants convert energy from sunlight into food. Their cell walls are made sturdy by a material called cellulose, and they are fixed in one place. Plants are divided into two groups: flower- and fruit-producing plants and those that don’t produce flowers or fruits. They include garden flowers, agricultural crops, grasses, shrubs, ferns, mosses, and conifers.

Animals

Animals are the most complex organisms on Earth. Animals are multi-celled organisms, eat food for survival, and have nervous systems. They are divided into vertebrates and invertebrates and include mammals, amphibians, reptiles, birds and fish.