Key Concepts in Science, Part-1

Here are ten science terms along with their definitions:

1. **Hypothesis**:

 A proposed explanation for a phenomenon or a prediction about the outcome of an experiment, which can be tested through further experimentation or observation.

2. **Cell**: 

The basic structural and functional unit of all living organisms, consisting of a membrane-bound structure that contains genetic material and performs various biological functions.

3. **Photosynthesis**: 

The process by which green plants, algae, and certain bacteria convert light energy into chemical energy in the form of glucose, utilizing carbon dioxide and water in the presence of chlorophyll.

4.**Gravity**:

 Gravity is the natural force of attraction between objects with mass, drawing them towards each other. It is responsible for phenomena such as the Earth's gravitational pull on objects, keeping them grounded, and governing the motion of celestial bodies in space, including the orbits of planets, moons, and stars.

5.**DNA**:

 DNA, short for Deoxyribonucleic acid, is a complex molecule that serves as the repository of genetic information in all known living organisms and many viruses. It carries the instructions necessary for the development, functioning, growth, and reproduction of organisms.

6. **Evolution**: 

The process of change in the inherited characteristics of biological populations over successive generations, driven by factors such as natural selection, genetic drift, and mutation, leading to the diversity of life on Earth.

7. **Atom**: 

The fundamental unit of a chemical element, consisting of a nucleus containing protons and neutrons, surrounded by electrons in orbitals. Atoms serve as the foundational units of matter.

8. **Ecosystem**: 

A biological community of interacting organisms and their physical environment, including both living (biotic) and non-living (abiotic) components, which together form a self-regulating and functional unit.

9. **Fossil**: 

The preserved remains or traces of ancient organisms, such as bones, shells, imprints, or impressions, which provide evidence of past life and are used by scientists to study the history of life on Earth.

10. **Climate Change**:

 Long-term alterations in temperature, precipitation patterns, and other climatic variables of the Earth's atmosphere, primarily caused by human activities such as burning fossil fuels, deforestation, and industrial processes, leading to global warming and significant environmental impacts.