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Biology

life science Maturity 9-11 Vital Level 2 Next article →

Biology is the scientific study of life. It explores how living things work and grow.

Biological cell
Biological cell

Biologists look at many different levels of life. They study tiny molecules and single cells. They also study whole animals and large ecosystems. This science helps us understand the origin of life. It also explains how life is spread across our planet. Biology is important because it helps solve many hard jobs. It helps us fight disease and understand climate change.

Life works through several important themes. First, the cell is the basic unit of all life.

Mitosis Stages
Mitosis Stages

Second, genes are the way traits are passed down. Third, evolution is the driver of all biological diversity. Fourth, living things must transform energy to stay alive.

CellRespiration
CellRespiration

Finally, organisms must keep their internal state stable. This is called homeostasis. Most living things are made of chemical elements. Oxygen, carbon, hydrogen, and nitrogen make up 96% of their mass.

3D model hydrogen bonds in water
3D model hydrogen bonds in water

Water is also vital because it helps molecules move and meet.

People have studied life for a very long time. Ancient scholars in Egypt and Mesopotamia studied medicine.

The Earth seen from Apollo 17 with transparent background
The Earth seen from Apollo 17 with transparent background

Later, the Greek philosopher Aristotle explored the diversity of life. In the 1700s, Carl Linnaeus created a way to name species.

Phylogenetic tree
Phylogenetic tree

Anton van Leeuwenhoek changed biology with a better microscope. He saw tiny bacteria and other microscopic life for the first time. These tools allowed scientists to see the tiny world of cells.

Many famous scientists helped build our modern knowledge. Charles Darwin and Alfred Russel Wallace studied natural selection.

Mutation and selection diagram
Mutation and selection diagram

This idea explains how life changes over time. Gregor Mendel began the study of genetics in 1865.

Punnett square mendel flowers
Punnett square mendel flowers

Later, James Watson and Francis Crick found the structure of DNA in 1953.

DNA simple horizontal
DNA simple horizontal

This discovery helped us understand the molecular code of life. In 1990, the Human Genome Project began mapping our entire genetic code.

Biology connects to many things you see every day. When you eat food, your body uses energy transformation.

Simple photosynthesis overview
Simple photosynthesis overview

This is similar to how a battery provides power to a toy. When you see a forest, you are seeing an ecosystem. In an ecosystem, plants and animals interact to move nutrients around. Even the water you drink is part of this story. Water helps dissolve small molecules so they can react. This allows the chemical processes of life to happen smoothly.

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🖼️ Images & Media (36)
File:Mitosis Stages.svg
Mitosis Stages.svg
File:Phylogenetic tree.svg
Phylogenetic tree.svg
File:Biological cell.svg
Biological cell.svg
File:CellRespiration.svg
CellRespiration.svg
File:Simple photosynthesis overview.svg
Simple photosynthesis overview.svg
File:Plant cell structure-en.svg
Plant cell structure-en.svg
File:Punnett square mendel flowers.svg
Punnett square mendel flowers.svg
File:Logistic Carrying Capacity.svg
Logistic Carrying Capacity.svg
File:Meiosis Overview new.svg
Meiosis Overview new.svg
File:Activation2 updated.svg
Activation2 updated.svg
File:3D model hydrogen bonds in water.svg
3D model hydrogen bonds in water.svg
File:Mutation and selection diagram.svg
Mutation and selection diagram.svg

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