Biochemistry is the branch of science that deals with the study of the chemical processes and substances that occur within living organisms. It is a fundamental field of study in understanding the molecular mechanisms of life and has applications in various fields such as medicine, agriculture, and industry. Here are some key points to summarize the knowledge of biochemistry:

1. Biomolecules: Biochemistry focuses on the study of various biomolecules that make up living organisms, such as proteins, carbohydrates, lipids, and nucleic acids. These biomolecules play essential roles in the structure, function, and regulation of biological processes.

2. Enzymes: Enzymes are biological catalysts that accelerate chemical reactions within cells. They are essential for metabolism, signaling, and other cellular processes. Enzymes are highly specific and are regulated by various factors such as pH, temperature, and substrate concentration.

3. Metabolism: Metabolism refers to the sum of all chemical reactions that occur within an organism. It can be divided into two main categories: catabolism, which involves the breakdown of molecules to produce energy, and anabolism, which involves the synthesis of molecules for cellular processes.

4. Cellular Respiration: Cellular respiration is the process by which cells convert nutrients into energy in the form of adenosine triphosphate (ATP). It involves a series of enzymatic reactions that occur in the mitochondria and produce ATP through the oxidation of glucose and other molecules.

5. DNA and RNA: DNA (deoxyribonucleic acid) and RNA (ribonucleic acid) are nucleic acids that carry genetic information in cells. DNA contains the genetic code that determines an organism's traits, while RNA plays essential roles in protein synthesis and other cellular processes.

6. Protein Structure and Function: Proteins are macromolecules made up of amino acids and play diverse roles in cells, such as enzymes, structural components, and signaling molecules. The structure of a protein determines its function, and changes in protein structure can affect its activity.

7. Gene Expression: Gene expression is the process by which genetic information from DNA is transcribed into RNA and translated into proteins. It is tightly regulated and involves various mechanisms such as transcription factors, RNA splicing, and post-translational modifications.

8. Signal Transduction: Signal transduction is the process by which cells receive and respond to external signals, such as hormones or growth factors. It involves signaling pathways that transmit signals from the cell surface to the nucleus and regulate gene expression and cellular processes.

9. Biochemical Techniques: Biochemistry utilizes various techniques to study biomolecules and their functions, such as chromatography, electrophoresis, mass spectrometry, and genetic engineering. These techniques help researchers understand the structure, function, and regulation of biological molecules.

In conclusion, biochemistry is a fascinating field of study that provides insights into the chemical basis of life. By understanding the molecular mechanisms of living organisms, biochemists can make significant contributions to various fields and improve our understanding of health, disease, and the environment.