Chapter 22: Nutrition and Digestion

Distinguish between the two eating disorders anorexia nervosa and bulimia.

Anorexia nervosa-results in self-starvation, due to an intense fear of gaining weight. Bulimia-characterized by binge eating followed by purging through vomiting, laxatives or exercise.

Obesity is defined as a too-high ____, which is a ratio of weight to height.

BMI

What is the difference between vitamins and minerals?

Minerals are an inorganic chemical element that an organism requires for proper bodily functioning, and vitamins are an organic nutrient that an organism requires in very small quantities.

Trace the pathway of food from the mouth all the way to the anus.

Mouth pharynx esophagus stomach small intestine large intestine anus.

Define the following terms: peristalsis; chyme; pepsin; bile; rectum.

Peristalsis-rhythmic waves of contraction of smooth muscles; propels food through a digestive tube and enables many animals to crawl. Chyme-a mixture of recently swallowed food and gastric juice. Pepsin-an enzyme present in gastric juice that begins the hydrolysis of proteins. Bile-a solution of salts secreted by the liver that emulsifies fats and aids in their digestion. Rectum-the terminal portion of the large intestine, where the feces are stored until they are eliminated.

Define malnutrition.

The absence of one or more essential nutrients from the diet.

What are the four stages of food processing? Place them in order.

Ingestion, digestion, absorption, elimination.

The small intestine has microscopic projections called ____ that are the major sites for absorption of nutrients in the human body.

villi

The main function of the large intestine is the absorption of

water.

What is an essential nutrient? How many of the 20 amino acids are considered essential?

A substance that an organism must absorb in preassembled form because it cannot synthesize the nutrient from any other material. Nine- histidine, isoleucine, leucine, lysine, methionine, phenylalanine, threonine, tryptophan and valine.

What is the difference between herbivore, carnivore, and omnivore?

Herbivore-mainly eats plants or algae. Carnivore- mainly eats animals. Omnivore-regularly eats animals as well as plants or algae.

State the main functions of the following: tongue; salivary glands; pharynx; esophagus.

Tongue-tasting, shaping and pushing the food to the back of the mouth. Salivary glands-secretes substances that lubricate food and begin the process of chemical digestion. Pharynx-receives food from the oral cavity; in terrestrial vertebrates, where the air and food passages cross. Esophagus-where food passes in a digestive tube, connecting the pharynx to the stomach.