It sounds like you're talking about Chemistry, Biology and Physics.
Chemistry is the study of particles and matter found within the Earth and the Universe. It looks at how matter is composed and all of the elements that exist. It is a huge force in modern technology, too. Modern technology relies on chemistry to be able to provide the materials that are required for many products and pieces of machinery out there. Chemistry is often seen in childish terms as explosions and sparks, but it actually provides a lot of important information for many industries. It also overlaps with the other areas of science, physics and biology.
Physics is another of the main branches of science taught at schools and universities alike. There are many kinds of physics, but in general, physics looks at how things move and forces that occur across the Universe. Astrophysics looks in particular at how things move throughout space, how the planets rotate and change and how the Universe was created. It is heavily involved with mathematics too, as forces require mathematical equations to be taught and understood. Scientists even need to use maths when they are creating and testing physics theories.
Biology is the study of all life on earth. It looks at plants, animals, humans, fungi, bacteria - everything that's alive. It looks at how the planet manages to provide us with everything we need and how natural landscapes provide for the animals. It is a diverse study that also looks at how the body works. It overlaps with chemistry in that chemists are required to provide drugs that can help the human body.