Question | Answer |
lung | An organ that exchanges gases between the atmosphere and the blood |
mucus | A slimy, protective substance on the exterior of many fish and some amphibians; a thick, sticky substance secreted by the mucous membranes in the human body |
pharynx | A musculatory tube that forms a section of some animals' digestive systems; the passageway between the mouth and the nose, esophagus, and larynx; also called the throat |
esophagus | In earthworms, a tubular passageway that carries food from the pharynx to the crop; in humans and vertebrate animals, a part of the digestive tract that connects the pharynx and stomach |
larynx | The short passageway that leads from the pharynx to the trachea, the sound-producing organ |
epiglottis | A think, flexible flap of tissue in front of the larynx that folds over and blocks the glottis during swallowing |
uvula | A structure at the back of the throat that prevents food from entering the nasal cavity when swallowing |
glottis | The space between the vocal folds that is a passageway for air |
trachea | In insects, one of the tiny tubes that branch throughout the body, carrying air to the tissues; in humans and vertebrate animals, the tube that carries air between the pharynx and the lungs |
bronchi | The two branches of the trachea; carry air to and from the lungs |
alveoli | The microscopic sacs in the lungs where gases are exchanged between the air and the bloodstream |
diaphragm | The part of a microscope that regulates the amount of light that passes through a specimen; the muscle that separates the thorax from the abdomen in mammals and humans and that aids in breathing |
digestion | The breakdown of food into smaller substances that the body's cells can use |
assimilation | The growth process by which living cells convert nutrients from food into cellular structures |
alimentary canal | The group of digestive organs forming the digestive tract that runs from mouth to anus |
peristalsis | Muscular contractions that move food along the alimentary canal |
salivary gland | A digestive gland that secretes saliva into the mouth |
chyme | The semiliquid mixture of digestive juices and partly digested food in the stomach and small intestine |
small intestine | The long, tubular organ in which most of the digestion and absorption of food occurs |
villi | Microscopic, fingerlike structures that line the wall of the small intestine and aid in the absorption of food molecules |
large intestine | The part of the digestive tract that extends from the end of the small intestine to the anus and absorbs water and minerals |
liver | The organ that produces bile, helps regulate substances in the blood, and stores vitamins and minerals |
bile | A substance secreted by the liver that helps separate lipids into small droplets to aid digestion |
pancreas | An organ that secretes enzymes into the small intestine to help perform digestion and also secretes the hormone insulin into the bloodstream |