Bio 102 - Ch.14 Digestion

Dietary fiber

An indigestible carbohydrate

Digestion

The breaking down of mechanically and chemically breaking down complex food molecules into simple molecules that the body can use.

Essential Amino Acid

Amino acids that the human body cannot synthesize on it’s own

Feces

Physical bodily waste

Mineral

Inorganic chemical elements

Nutrient

a component of food that is utilized by the body.

Vitamin

organic compounds (other than carbohydrates, fats, and proteins) that the body needs for metabolic purposes but is unable to produce.

Bulimia

A disease that causes a person to binge-eat and then purge (vomit) to avoid gaining weight. Can coexist with either obesity or anorexia nervosa.

Anorexia

A severe psychological disorder characterized by an irrational fear of getting fat.

Pellagra

A systemic disease caused by a severe deficiency of niacin (vitamin B3). It affects the whole body and can eventually lead to death.

Scurvy

a disease caused by a serious vitamin C deficiency. Not eating enough fruits and vegetables is the main cause of the disease.

Rickets

A bone disorder characterized by bowing of the legs, it is caused by defective mineralization of the skeleton. Occurs when the body lacks enough Vitamin D or calcium to build and maintain strong bones

Chemical Digestion

The breaking down of macromolecules to small organic molecules that can
be absorbed by various enzymes and stomach acid.

Mechanical Digestion

the chewing of food in the mouth and continues with the churning and mixing of food in the stomach.

Amylase

the enzyme which begins the process of digesting starch.

Lipase

A pancreatic enzyme, digests fat molecules in the fat droplets after they have been emulsified by bile salts

Pepsin

Made from Pepsinogen when exposed to HCI, is also present in gastric juice. Acts on proteins, which are polymers of amino acids, to produce peptides.

Trypsin

A pancreatic enzyme that digests protein.

Insulin

A hormone that along with glucagon, helps to keep the blood glucose level within normal limits. Secreted by the pancreas

Glucagon

A hormone that along with insulin, helps to keep the blood glucose level within normal limits. Secreted by the pancreas

Oral Cavity

Also called the mouth, it is the site where food is ingested.

Pancreas

An organ with endocrine and exocrine functions. The endocrine function that secretes the enzymes, insulin and glucagon. The exocrine function produces a ‘juice’ that contains sodium bicarbonate that helps to neutralize stomach acid and digestive enzymes for various foods.

Pharynx

a region that receives air from the nasal cavities and food from the mouth

Saliva

What keeps the mouth moist and contains the enzyme salivary amylase, which begins the process of digesting starch.

Gallbladder

Stores excess bile from the liver

Liver

Produces bile which aids in digestion, also filters blood. Extremely important organ.

Teeth

the primary means of mechanical digestion in the digestive tract

Tongue

A muscular organ that is composed of skeletal muscle that contracts to change the shape of itself. Helps with digestion and speech, also has taste buds, which are activated by the presence of food.

Salivary Gland

The three glands within the human mouth that produce saliva

Small Intestine

The first part of this organ is called the duodenum, the middle the jejunum, and the remainder the ileum. Contains villi that absorb nutrients from broken down ingested food.

Large Intestine

Includes the cecum, colon, rectum, and anal canal. Turns food waste into solid feces.

Stomach

An organ that physically (churns) and chemically breaks down food. Food that leaves this organ is called chyme. Contains pepsin to break down proteins

Swallowing Reflex

A reflex action that allows food to enter the esophagus.

Anus

Where defecation occurs; the expulsion of feces

Colon

The longest part of the large intestine, removes water and some nutrients from digested food.

Bile

A greenish-yellow fluid produced by the liver that assists in digesting fats

Esophagus

the muscular tube in your body that carries food and liquid from your throat (pharynx) to your stomach, where it is then digested.