Proteins

Proteins are large, complex molecules that play many critical roles in the body. They are made up of smaller units called amino acids, which are linked together in a specific sequence. There are 20 different types of amino acids that can be combined to form a wide variety of proteins, each with its own unique structure and function.

Functions of Proteins

Proteins have a wide range of functions in the body, including:

• Enzymes: Proteins act as biological catalysts, speeding up chemical reactions in the body.
• Structural Support: Proteins provide structure and support for cells, tissues, and organs.
• Transport: Some proteins help transport molecules, such as oxygen, in the blood.
• Immune Function: Antibodies are specialized proteins that help the body defend against foreign invaders.
• Hormones: Some proteins act as hormones, regulating various physiological processes.
• Energy Source: In times of need, proteins can be broken down to provide energy for the body.

Sources of Proteins

Proteins are found in a variety of foods, including:

• Meat and poultry
• Fish and seafood
• Dairy products
• Eggs
• Legumes (beans, lentils, peas)
• Nuts and seeds

Study Guide

When studying proteins, it's important to focus on the following key points:

1. The structure of proteins, including the role of amino acids in protein formation.
2. The functions of proteins in the body, with specific examples of proteins that serve each function.
3. The sources of dietary proteins and the importance of including a variety of protein sources in the diet.
4. The concept of protein quality and the importance of consuming complete proteins that provide all essential amino acids.

Understanding proteins is essential for grasping the fundamentals of human biology and nutrition. By mastering the properties and functions of proteins, you can gain a deeper understanding of how the human body functions and the role of nutrition in maintaining good health.