Animal structures and functions quiz #1

• Nutrient


  A chemical that must be obtained by an organism from its environment in order to survive; nutrients provide the raw material for growth and repair and may be a source of emergy
• Metabolism


  The set of chemical reactions that in living organisms that are necessary to maintain life
• Hormone


  A chemical signal or messenger molecule, circulated through the body and used to coordinate cellular functions
• Triglyceride


  A lipid composed of glycerol and three fatty acids that are bonded together
• Mineral

  An element, such as calcium or phosphorus , required by the body in small amounts; plays a roll in cell process and repair
• Vitamin


  An organic molecule that the body requires in small amounts as an essential nutrient
• Gastrovascular cavity


  A simple, sac-like digestive cavity that has only one opening through which food is taken in and wastes are expelled
• Gastrointestinal tract


  Also known as the GI tract, is the passageway or tube that extends from the mouth to the anus and in which the process of digestion takes place
• Enzyme


  Any chemical produced by cells that facilitates biochemical reactions in the body, such as those involved in digestion and metabolism; all enzymes are proteins
• Amylase


  An enzyme that breaks down complex carbohydrates
• Mucus


  A protective secretion produced by the epithelial cells that form the mucous membrane
• Esophagus


  An organ consisting of a muscular tube that passes food from the pharynx to the stomach
• Peristalsis


  The rhythmic, involuntary wave-like contractions of the smooth muscles of the gastrointestinal tract
• Sphincter


  A circular muscle that contracts to close an opening in the body
• Chyme


  A semi-liquid mixture of food and gastric juice
• Gastrin


  A hormone that stimulates the release of hydrochloric acid and pepsinogen in the stomach
• Pepsin


  A protein-digesting enzyme produced in the stomach
• Ulcer


  A lesion or open sore on the epithelium of an organ
• Villus


  A small, finger-like projection of the inner layer of the small intestine mucosa
• Microvillus


  A microscopic projection of the cell membrane of certain types of epithelial cells; greatly increases the surface area of the cell
• Lacteal


  A lymphatic vessel within a villus, through which digested fats enter the circulatory system
• Trypsin


  A protein-digesting enzyme produced from trypsinogen
• Secretin


  A hormone secreted by the duodenum that stimulates pancreatic and bile secretions
• Enterokinase


  An enzyme of the small intestine that converts inactive trypsinogen into trypsin
• Lipase


  An enzyme that digests lipids
• Bile


  A substance that emulsifies fats for faster breakdown by lipases; produced by the liver
• Passive transport


  The movement of materials across a cell membrane without any expenditure of the cell's energy
• Concentration gradient

  The difference in the number of molecules or ions of a substance in a given volume between adjoining areas
• Facilitated diffusion


  The diffusion of molecules across a cell membrane via a transport protein
• Active transport


  The transportation of materials through a cell membrane using energy from the cell
• Cecum

  A blind pouch at the upper end of the large intestine
• Colon


  The longest part of the large intestine
• Rectum


  The lower 20cm of the large intestine, generally referred to as the lower bowel, where feces are stored
• Anus


  The opening at the lower end of the large intestine through which digestive wastes are eliminated from the body
• Egestion


  The removal of waste food materials from the body
• Feces


  The undigested material that is eliminated as waste from the body
• Endoscopy


  Any medical procedure that uses an endoscope to look inside the body
• Nausea


  The feelings associated with having the urge to vomit
• Emesis


  The expulsion of stomach contents through the esophagus and the mouth; also known as vomiting
• Diarrhea


  Loose or watery feces