Question

What are the mechanical actions involved in the digestion of foods?

1) Chewing
2) Mixing with saliva
3) Peristalsis
4) Segmentation

Answer 1

Mechanical digestion involves chewing, mixing with saliva, peristalsis, and segmentation to physically break down food into smaller pieces and mix it with digestive juices, enhancing the digestion process without altering the food's chemical nature.

Step-by-step explanation:

The mechanical actions involved in the digestion of foods are essential components of the digestive process. These actions include:

• Chewing - This is done by the teeth and jaw, breaking down food into smaller pieces, known as mastication.
• Mixing with saliva - Saliva from the salivary glands moistens the food to facilitate mechanical and chemical digestion.
• Peristalsis - Characterized by alternating waves of muscle contraction and relaxation, peristalsis moves food through the digestive tract from the pharynx to the stomach.
• Segmentation - This entails localized contractions of circular muscle in the small intestine, which mix the food with digestive juices and facilitate absorption by moving food back and forth.

Mechanical digestion is thus a purely physical process that increases the surface area and mobility of the food without changing its chemical nature, preparing it for chemical digestion down the line.