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study of body structure


processes and functions of an organism


groups of similar cells that perform a specific function in an organism

epithelial tissue

membranous tissue covering internal organs and other internal surfaces of the body

connective tissue

tissue that holds organs in place and binds different parts of the body together

nervous tissue

tissue that receives messages from the body's external and internal environment, analyzes the data, and directs the response

muscle tissue

a body tissue that contracts or shortens, making body parts move


group of tissues that work together to perform closely related functions

organ systems

a group of organs that work together in performing vital body functions

interstitial fluid

liquid found between the cells of the body that provides much of the liquid environment of the body


an organ having nerve endings (in the skin or viscera or eye or ear or nose or mouth) that respond to stimulation

control center

this determines the next action in a feedback system by sending output to an effector, processes the signal and sends instructions


an organ (a gland or muscle) that becomes active in response to nerve impulses

negative feedback system

Reverses a change in a controlled condition

metabolic rate

The rate at which the body burns calories to produce energy.


describes a reaction that absorbs energy from the surroundings


cold blooded

essential nutrients

substances the body requires for normal growth and health but cannot manufacture in sufficient amounts: they must be obtained int he diet.

essential amino acids

Amino acids that are needed, but cannot be made by the body; they must be eatin in foods

essential fatty acids

fats needed by the body that must be consumed in the diet because the human body cannot manufacture them


Essential nutrients that do not yield energy, but that are required for growth and proper functioning of the body.


substances that the body cannot manufacture but that are needed for forming healthy bones and teeth and regulating many vital body processes


organism that obtains energy by eating only plants


organism that obtains energy by eating both plants and animals


any animal that feeds on flesh


the process of taking food into the body through the mouth (as by eating)


the organic process by which food is converted into substances that can be absorbed into the body

enzymatic hydrolysis

the process in digestion that splits macromolecules from food by the enzymatic addition of water


the process of absorbing nutrients into the body after digestion


The passing of undigested material out of the digestive compartment

intracellular digestion

The joining of food vacuoles and lysosomes to allow chemical digestion to occur within the cytoplasm of a cell.


The process by which nutrient molecules pass through the wall of your digestive system into your blood

extracellular digestion

process in which food is broken down outside the cells in a digestive tract

gastrovascular cavity

An extensive pouch that serves as the site of extracellular digestion and a passageway to disperse materials throughout most of an animal's body

alimentary canals

complete digestive tract consisting of a tube extending between 2 openings: mouth and anus, food moves in 1 direction and can be organized into special regions


a clear liquid secreted into the mouth by the salivary glands and mucous glands of the mouth

salivary amylase

Enzyme in saliva that breaks down starch


A term used to describe food after it has been chewed and mixed with saliva


throat; passageway for food to the esophagus and air to the larynx


a flap of cartilage that covers the windpipe while swallowing


the passage between the pharynx and the stomach


the process of wave-like muscle contractions of the alimentary tract that moves food along


an enlarged and muscular saclike organ of the alimentary canal

gastric juices

a thin, clear, virtually colorless acidic fluid secreted by the stomach glands and active in promoting digestion.


Enzyme that breaks down proteins in the stomach


The inactive form of pepsin

acid chyme

a mixture of recently swallowed food and gastric juice

pyloric sphincter

opening from the stomach into the duodenum, Controls passage of food from stomach to small intestine

small intestine

digestive organ in which most chemical digestion takes place


first portion of the small intestine




a substance produced by the liver that breaks up fat particles


main source of energy for the body, Organic compounds made of carbon, hydrogen, and oxygen atoms in the proportion of 1:2:1.

pancreatic amylase

Enzyme that breaks down starch into disaccharides (Maltose, Lactose, Sucrose)


macromolecules that contain nitrogen as well as carbon, hydrogen, and oxygen


an enzyme from the pancreas that digests proteins in the small intestine


enzyme that breaks down peptide bonds, mostly inactive


further hasten digestion by splitting small peptides, Enzyme in small intestine that split small peptides


Protein digesting enzyme that is activated by trypsin; released as procarboxypeptidase (inactive form)


An enzyme found within the small intestine that splits off one amino acid at a time, beginning at the opposite end of the polypeptide containing a free carboxyl group.

nucleic acid

an organic compound, either RNA or DNA, whose molecules are made up of one or two chains of nucleotides and carry genetic information


nutrient that stores energy, cushions organs, and helps the body absorb vitamins


process in which bile breaks down fat


enzyme that breaks down fat in pancreas


Small fingerlike projections on the walls of the small intestines that increase surface area


Tiny hair-like projections of the cytoplasmic membrane located only in the small intestine to facilitate absorption by increasing surface area.


any of the lymphatic vessels that convey chyle from the small intestine to the thoracic duct

hepatic portal vessel

A large circulatory channel that conveys nutrient-laden blood from the small intestine to the liver, which regulates the blood's nutrient content


large and complicated reddish-brown glandular organ located in the upper right portion of the abdominal cavity


hormone produced in the stomach wall that stimulates sustained secretion of gastric juice


intestinal mucosa cells secrete this hormone that inhibit gastric gland activity during inhibitory component of intestinal phase called the enterogastric reflex


peptic hormone produced by the mucous lining of the small intestine


secreted by intestinal cells, acts in opposition to ghrelin as an appetite suppressor

large intestine

the last section of the digestive system, where water is absorbed from food and the remaining material is eliminated from the body


the part of the large intestine between the cecum and the rectum


first part of the large intestine


small pouch, which has no function in digestion, attached to the cecum


The last part of the digestive tract, through which stools are eliminated

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