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Digestive System Vocabulary

Essential Nutrients
Nutrients required for normal body functioning that either cannot be synthesized by the body at all, or cannot be synthesized in amounts adequate for good health and thus must be obtained from a dietary source
Improper nutrition or an insufficient diet. Malnutrition is the condition that occurs when your body does not get enough nutrients
Essential Amino Acids
Amino acids are organic compounds that combine to form proteins. Essential amino acids cannot be made by the body. As a result, they must come from food.
The nine essential amino acids are: histidine, isoleucine, leucine, lysine, methionine, phenylalanine, threonine, tryptophan, and valine
Essential Fatty Acids
Only two fatty acids are known to be essential for humans: alpha-linolenic acid and linoleic acid. Cannot be manufactured in the body. Helps cellular function.
Any of a group of organic compounds that are essential for normal growth and nutrition
Naturally occurring inorganic substance
The process of taking food into the body through the mouth for digestion or absorption
The process of breaking down food by mechanical and enzymatic action in the stomach and intestines into substances that can be used by the body
The body absorbs the necessary nutrients to maintains the body's homeostasis and provide energy for the body's activities
The conversion of nutrient into the fluid or solid substance of the body by the processes of digestion and absorption
Intracellular Digestion
Type of digestion in which food is digested inside specialized cells that pass nutrients to other cells by diffusion
Extracellular Digestion
Process in which food is broken down outside the cells in a digestive tract
Alimentary Canals
Complete digestive tract consisting of a tube extending between 2 openings: mouth and anus, food moves in one direction and can be organized into special regions
Involuntary waves of muscle contraction that keep food moving along in one direction through the digestive system
Circular muscle that surrounds a tube such as the urethra and constricts the tube when it contracts
Salivary Amylase
An enzyme secreted by the salivary glands that begins the breakdown of complex sugars and starches
Gastric Juice
Acidic fluid secreted by the stomach glands and active in promoting digestion
An enzyme present in gastric juice that begins the hydrolysis of proteins
The inactive form of pepsin that is first secreted by specialized (chief) cells located in gastric pits of the stomach
An enzyme that splits small peptides into amino acids
An enzyme from the pancreas that digests proteins in the small intestine
A protein enzyme that hydrolyzes the peptide bond of an amino acid
An enzyme found within the small intestine that splits off one amino acid at a time
Break down nucleus acids
An enzyme secreted in the digestive tract that catalyzes the breakdown of fats into individual fatty acids that can be absorbed into the bloodstream