2. What are proteins? Enzymes,antibodies,many hormones,and substances that help the blood to clot,are all proteins. Enzymes,antibodies,many hormones,and substances that help the blood to clot,are all proteins. Protein is the material basement of life,that is,we can’t have life without protein. Protein is the material basement of life,that is,we can’t have life without protein. There is protein in cells of organisms and all important compositions. There is protein in cells of organisms and all important compositions. Protein accounts for 16%~~20% of people’s weight. Protein accounts for 16%~~20% of people’s weight.

4. Where are they from? Where are the amino acid from? Where are the amino acid from? Of the basic set of 20 amino acids, there are 8 that human beings cannot synthesize. Of the basic set of 20 amino acids, there are 8 that human beings cannot synthesize.

5. Proteins!

6. Protein Denaturation

7. How they work? Enzymes Enzymes The best-known role of proteins in the cell is as enzymes, which catalyze chemical reactions. Enzymes are usually highly specific and accelerate only one or a few chemical reactions. Enzymes carry out most of the reactions involved in metabolism, as well as manipulating DNA in processes such as DNA replication, DNA repair, and transcription. The best-known role of proteins in the cell is as enzymes, which catalyze chemical reactions. Enzymes are usually highly specific and accelerate only one or a few chemical reactions. Enzymes carry out most of the reactions involved in metabolism, as well as manipulating DNA in processes such as DNA replication, DNA repair, and transcription.

8. Many proteins are involved in the process of cell signaling and signal transduction. Some proteins, such as insulin, are extracellular proteins that transmit a signal from the cell in which they were synthesized to other cells in distant tissues. Others are membrane proteins that act as receptors whose main function is to bind a signaling molecule and induce a biochemical response in the cell. Many proteins are involved in the process of cell signaling and signal transduction. Some proteins, such as insulin, are extracellular proteins that transmit a signal from the cell in which they were synthesized to other cells in distant tissues. Others are membrane proteins that act as receptors whose main function is to bind a signaling molecule and induce a biochemical response in the cell. Cell signaling and ligand binding

9. Structural proteins Structural proteins confer stiffness and rigidity to otherwise-fluid biological components. Most structural proteins are fibrous proteins. Structural proteins confer stiffness and rigidity to otherwise-fluid biological components. Most structural proteins are fibrous proteins. Other proteins that serve structural functions are motor proteins such as myosin, kinesin, and dynein, which are capable of generating mechanical forces. Other proteins that serve structural functions are motor proteins such as myosin, kinesin, and dynein, which are capable of generating mechanical forces.

10. How much do we need? In our daily life, we generally get protein from meat, egg, milk, nuts and soy-based foods(soybean is better). In our daily life, we generally get protein from meat, egg, milk, nuts and soy-based foods(soybean is better). The quality of protein which comes from animals is better than plant's. The quality of protein which comes from animals is better than plant's.

11. A piece of meat that has the same size as a playing card contains about 30~35g protein, a cup of milk contains about 8~10g protein. So a piece of meat, a cup of milk, some beans, some vegetables and some rice can provide with enough protein(60~70g). A piece of meat that has the same size as a playing card contains about 30~35g protein, a cup of milk contains about 8~10g protein. So a piece of meat, a cup of milk, some beans, some vegetables and some rice can provide with enough protein(60~70g). It is better that 1/3 protein is animal protein and 2/3 is plant protein. It is better that 1/3 protein is animal protein and 2/3 is plant protein. Because human body cannot storage protein, we should get some protein each three meals. Because human body cannot storage protein, we should get some protein each three meals.