Digestive Systems and Nutrition

Flashcards for reviewing key concepts related to digestive systems and nutrition.

Calories

Units measuring energy in foods.

Nutrients

Essential substances in food that provide energy and support growth.

Heterotrophs

Organisms that cannot produce their own food and must consume other organisms.

Autotrophs

Organisms that can produce their own food from inorganic substances.

Herbivores

Organisms that primarily consume plants.

Carnivores

Organisms that primarily consume meat.

Omnivores

Organisms that eat both plants and animals.

Intracellular Digestion

Digestion that occurs within a cell.

Extracellular Digestion

Digestion that occurs outside of cells, within a digestive cavity.

Chyme

The mixture of partially digested food and gastric juice.

Villi

Small fingerlike projections in the small intestine that increase surface area for absorption.

Microvilli

Even smaller projections on villi that further increase surface area for absorption.

Peristalsis

Rhythmic wave of muscular contractions that moves contents through the digestive tract.

Bile

An emulsifier produced by the liver that aids in fat digestion.

Saliva

A fluid secreted by salivary glands that moistens food and contains digestive enzymes.

Pancreatic Juice

Digestive fluid produced by the pancreas that contains enzymes and bicarbonate.

Gallbladder

A muscular sac that stores and concentrates bile before releasing it into the small intestine.

Cecum

The blind end of the large intestine where the small intestine connects.

Feces

Undigested material, water, and many bacteria expelled from the body.

Essential Amino Acids

Amino acids that cannot be synthesized by the body and must be obtained from food.