Structural functions:

* Support and shape: Proteins like collagen and keratin provide structural support to tissues like skin, bones, cartilage, tendons, and hair.

* Movement: Proteins like actin and myosin are crucial for muscle contraction and movement.

* Cell structure: Proteins form the cytoskeleton, which gives cells their shape and helps in transport and movement within the cell.

Regulatory functions:

* Enzymes: Proteins act as catalysts, speeding up biochemical reactions in the body. They regulate metabolism, digestion, and other essential processes.

* Hormones: Some proteins act as hormones, carrying messages throughout the body to regulate various functions like growth, development, and metabolism.

* Antibodies: Antibodies are proteins that recognize and neutralize foreign invaders like bacteria and viruses, playing a key role in the immune system.

* Transport: Proteins like hemoglobin carry oxygen in the blood, and other proteins transport nutrients and molecules throughout the body.

* Gene expression: Proteins can regulate gene expression, controlling which genes are turned on or off.

In summary: Proteins are essential components of the body, performing a wide range of functions, from providing structural support to regulating complex cellular processes. Their diverse roles are crucial for maintaining life and ensuring proper body function.