Living things are all around us, in gardens, parks, homes, and schools. Plants, animals, and people are living things because they grow, change, and need care. Learning what living things need helps children understand how to care for pets, plants, and nature.
A garden is a good place to see many living things meeting their needs.
Understanding What Living Things Need
Food gives organisms energy and building materials. Animals get these materials by eating plants or other animals. A rabbit can turn grass into energy for hopping, keeping warm, and growing fur.
An owl gets energy by eating prey. This creates food chains. Energy enters most food chains from the Sun, then moves through plants and animals.
At each step, some energy is used up as heat, so a habitat usually has many plants, fewer plant eaters, and even fewer hunters. People need a varied diet because different foods provide different nutrients for bones, muscles, blood, and the brain.
Water does much more than stop thirst. It carries dissolved nutrients around bodies and helps cells carry out chemical reactions. It can help regulate temperature when sweat evaporates from skin.
Plants use water to keep their stems and leaves firm. They pull water upward from roots through tiny tubes. When water is scarce, many plants droop because their cells lose pressure.
Some organisms have special ways to save water. Cacti store it in thick stems. Desert animals may rest in cooler shelters during the day.
Too much water can be harmful too. Flooded soil has little air space, which can prevent plant roots from working properly.
Air supplies gases that cells need. Animals and people take in oxygen, which helps release energy from food inside cells. Fish take oxygen from water through their gills, since oxygen is dissolved there.
Plants use carbon dioxide as one ingredient for making sugar in their leaves. They release oxygen during this process. Plants still need oxygen for their own cells, especially when there is no light.
This is why roots need loose soil with air gaps. Packed or waterlogged soil can make it hard for roots to get enough oxygen.
Shelter is not simply a place to sleep. It protects an organism from weather, predators, injury, and extreme temperatures. A nest can keep eggs warm and hidden.
A burrow can stay cooler than the ground above it. Tree bark gives insects small spaces to hide. Homes give people protection, privacy, and a safe place to rest.
Space matters because organisms need room to find resources and avoid too much competition. When a habitat is changed by building, pollution, drought, or cutting down trees, several needs can be affected at once. When studying a local plant or animal, notice where it gets energy, where it finds water, how it exchanges gases, and what features of its habitat keep it safe.
Key Facts
- Living things need water to stay healthy and grow.
- Plants need sunlight, water, air, soil, and space.
- Animals need food, water, air, shelter, and space.
- People are living things, so we need food, water, air, shelter, and space too.
- Needs: air + water + food + space + shelter.
- Plants make their own food using sunlight, air, and water.
Vocabulary
- Living thing
- A living thing is something that grows, changes, and needs food or energy, water, and air.
- Need
- A need is something a living thing must have to stay alive and healthy.
- Shelter
- Shelter is a safe place that protects a living thing from danger, weather, or harm.
- Nutrients
- Nutrients are helpful parts of food or soil that living things use to grow and stay strong.
- Habitat
- A habitat is the place where a plant or animal lives and gets what it needs.
Common Mistakes to Avoid
- Thinking only animals need food is a mistake because plants also need energy, but they make their own food using sunlight, air, and water.
- Forgetting that plants need air is a mistake because plants use air to help make food and grow.
- Giving a plant too much water is a mistake because roots can be harmed if the soil stays too wet for too long.
- Thinking shelter is only a house is a mistake because shelter can be a nest, burrow, tree, cave, or any safe place.
Practice Questions
- 1 A class has 4 plants. Each plant needs 1 cup of water today. How many cups of water are needed in all?
- 2 Three rabbits each need 2 carrot pieces. How many carrot pieces are needed for all 3 rabbits?
- 3 A plant is kept in a dark closet and is not watered. Explain which needs are missing and what may happen to the plant.