Biology

Biology is the branch of science that studies living things — from the tiniest bacteria to the largest animals and plants. The word comes from Greek: bios means life, and logos means study. Biologists explore how living things are built, how they survive, and how they interact with one another and their environment.

All living things, called organisms, share certain features. They grow, use energy, respond to their surroundings, and can reproduce to make more of their kind. Biology looks at how these processes work inside each organism. For example, it studies how a tree uses sunlight to make food through photosynthesis, or how the human body pumps blood to every part uphotosynthesis.

Biology is divided into many fields. Botany focuses on plants, zoology on animals, and microbiology on tiny organisms like bacteria. Ecology studies how living things depend on each other and their environment, while genetics explores how traits are passed from parents to offspring. Together, these areas help scientists understand how all life forms are connected.

Biologists also study cells, the smallest units of life. Every living thing is made up of one or more cells. Some organisms, like bacteria, have only one cell, while others, like humans, have trillions. Inside cells are tiny parts that perform different jobs, such as providing energy or carrying genetic information. Understanding cells helps explain health, disease, and growth.

Biology also explains how life changes over time. Through evolution, species adapt to their environments. This process, happening over millions of years, has led to the great diversity of life we see today — from ocean fish to flying birds and forest plants. Studying fossils helps biologists trace how life forms have changed across earth's history.

In everyday life, biology plays an important role. It helps doctors treat illnesses, farmers grow healthy crops, and scientists protect endangered species. It also helps us understand our own bodies, what we eat, and how our actions affect nature. Biology reminds us that all living things are part of one connected world — and that caring for life means caring for the planet itself.