Biochemistry

1. Biochemistry: Biochemistry is about studying life at the tiny level of molecules. It looks at how the building blocks of life work together, how cells do their jobs, and how chemical processes let living things grow, make babies, and react to their surroundings.

2. What makes something “alive”: Living things have a few key features:
   • They’re organized, starting with cells as the basic unit.
   • They use energy from food to power their activities.
   • They grow bigger and can make more of themselves.
   • They keep their insides stable even when things change outside.

3. Cells - the building blocks of life: Cells are the smallest things we can call “alive.” They’re made of even smaller parts that each do different jobs. There are simple cells (like in bacteria) and more complex cells (like in plants and animals). All cells have a skin-like covering that controls what goes in and out.

4. The ingredients of life: Living things are made of four main types of molecules:
   • Proteins: These do lots of jobs, like speeding up chemical reactions, giving shape to cells, and helping cells talk to each other.
   • DNA and RNA: These store and pass on the instructions for making living things.
   • Fats: These make up cell walls and store energy.
   • Carbohydrates: These provide energy and help give structure to cells.

5. What proteins are made of: Proteins are like long chains made of smaller pieces called amino acids. Each amino acid has three parts: a part with nitrogen, a part with carbon and oxygen, and a unique part that gives it special properties. How these amino acids are arranged determines what shape the protein takes and what job it does.

6. What DNA is: DNA is like a long instruction manual for building and running living things. It’s made of smaller units called nucleotides. Each nucleotide has three parts: a sugar, a phosphate group, and one of four special molecules (A, T, C, or G). The order of these A, T, C, and G molecules spells out the instructions for making proteins.

7. How DNA instructions become proteins: The process of turning DNA instructions into proteins happens in two steps:
   1. The DNA instructions are copied into a similar molecule called RNA.
   2. Special cell parts called ribosomes read the RNA and use it as a guide to build proteins.

8. How living things use energy: All the chemical reactions that happen in living things to keep them alive are called metabolism. This includes breaking down food to get energy and using that energy to build new parts of the body.

9. How cells make energy: Cells break down food molecules like sugar to make energy. This happens in a few steps:
   1. First, sugar is broken down into smaller pieces, releasing a bit of energy.
   2. These pieces are broken down further, releasing more energy.
   3. Finally, the leftover parts are used to make lots of energy in a process that uses oxygen.

   The energy is stored in a molecule called ATP, which cells use like a battery to power their activities.

10. Enzymes - nature’s helpers: Enzymes are special proteins that help chemical reactions happen faster. They work by grabbing onto the molecules involved in a reaction and helping them change more easily.

11. Keeping balance in the body: Living things need to keep their insides stable even when things change outside. They do this through various processes, like using hormones to control blood sugar or using special chemicals to keep the right level of acidity in the body.

12. How scientists study biochemistry: Scientists study biochemistry using a step-by-step process:
    1. They observe how molecules behave in living things.
    2. They come up with ideas about how these molecules might work.
    3. They test these ideas with experiments.
    4. If their ideas work out, they use them to form bigger theories about how life works at a molecular level.

In summary, biochemistry looks at how tiny parts in living things work together to keep living things alive.