Question

Digestion, Absorption, Transport, Metabolism Salivary amylase, Chyme, Gastrin, Pepsin Pancreatic amylase, Trypsin, Chymotrypsin, Carboxypeptidase, Pa Mucosal folds, Villi, Microvilli Catabolism, Anabolism, Glycogenesis, Lipogenesis, Adipose tissue ncreatic lipase Chapter 5 Short Answer Questions 1. Describe the role of muscles & nerves with mechanical digestion. 2. Describe how the 5 gastrointestinal secretions assist with chemical d 3. Describe mechanical & chemical digestion in the mouth and esophagus. Be specific, include enzymes igestion. 4. Describe mechanical & chemical digestion in the stomach (like above).

Answer 1

1. The tongue consists of skeletal muscles that allow the food to move around. The smooth muscle connects the pharynx into the esophagus and allows the food to enter into the esophagus. The esophagus is a muscular layer that allows the food for peristaltic movement. The stomach consists of four layers such as serosa, muscularis, submucosa, and mucosa which helps for mixing of food and protects the lining of the stomach from the acid. Extrinsic nerves involved in the mechanical digestion of food.

2. Gastrointestinal secretion assists with chemical digestion:

a. Saliva that secretes in the mouth helps in the digestion of carbohydrates through the enzyme amylase.

b. Gastric juice secreted by the stomach helps in the self -digestion, and production of digestive enzymes such as pepsin helps in the digestion of protein into amino acids.

c. Bile produced in the liver helps in the digestion of lipids and stores glucose in the form of glycerol.

d.Trypsin and chymotrypsin secreted by the pancreas involved in the breakdown of protein into amino acids.

.e. Protease, lipase, and nuclease secrete from the small intestine help in reabsorption of nutrients and water.

3. Mechanical and Chemical digestion in the mouth and esophagus:

Mechanical digestion is the breakdown of food into smaller pieces by physically. The tongue allows the food to move around for the effective breakdown of food where mechanical digestion initiates. Salivary glands secrete saliva that helps in chewing of food in the mouth. Chemical digestion begins when the amylase breaks down the carbohydrates. Saliva contains mucin that acts as a lubricant and allows the bolus to enter into the esophagus. Epiglottis prevents the food from entering into the stomach. The esophagus is a muscular tube that transports the food by squeezes of the smooth muscle(peristalsis).

4. Mechanical and chemical digestion of the stomach:

The stomach is a muscular bag where the mixing of food takes place called churning. It controls the passage of food into the small intestine. The stomach secretes digestive enzymes pepsin which digests the protein. Hcl secreted in the stomach and mucus protects the lining of the stomach from gastric acid. The secretion of bile from the liver and pancreatic enzymes such as amylase, protease, lipase, nuclease helps in further digestion of carbohydrates, proteins, and fats.