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animal that eats only plant or algae


animal that eats meat


animal that eats plants and meat


act of eating, first main stage of food processing


mechanical and chemical breakdown of food into small molecules for body to absorb, second stage of food processing

Gastrovascular Activity

digestive compartment with single opening as the mouth


opening through which food is taken


organ in a digestive tract that receives food from oral cavity


channel that conducts food by peristalsis, from pharynx to stomach


pouch like organ in digestive tract that grinds food


pouch like organ in digestive tract where food is mechanically ground


region of digestive tract located between gizzard and anus where chemical digestion and nutrient absorption occur


opening through which human waste is expelled

Alimentary Canal

digestive tract consisting of tube running between mouth and anus


pouch-like organ in digestive tract where food is softened and can temporarily be stored


ringlike valve, consisting of modified muscles that regulates passage between some compartments of alimentary canal


salivary gland secretion that contains substances to lubricate food

Oral Cavity

mouth of an animal

Salivary Glands

glands associated with oral cavity that secret substances to lubricate food and begin process of chemical digestion

Gastric Juice

collection of fluids secreted by stomach


digestive hormone that stimulates secretion of gastric juice


mixture of partially digested food and digestive juices formed in stomach

Small Intestine

longest section of alimentary canal


gland with dual functions: digestive portion secretes enzymes into small intestine, endocrine portion secretes insulin and glucagon into blood


mixture of substances produced by liver and stored in gallbladder, emulsifies fats


organ that stores bile and releases it into the small intestine


first portion of the vertebrate small intestine after stomach, where chyme mixes with bile and digestive enzymes


fingerlike projection of inner surface of small intestine

Large Intestine

colon, tubular portion or vertebrate alimentary tract between small intestine and anus, water absorption and formation of waste


blind outpocket at beginning of of large intestine


small fingerlike extension of vertebrate cecum


terminal portion of large intestine where waste is stored until eliminated

Metabolic Rate

total amount of energy an animal uses in a unit of time

Basal Metabolic Rate (BMR)

number of kilocalories a resting animal requires to fuel its essential body processes


condition that results from a diet that consistently supplies less chemical energy than the body requires


long term absence from a diet or essential nutrients


consumption of more food energy than the body needs

Circulatory System

organ system that transports materials such as nutrients, O2 and hormones to body cells


muscular pump that propels blood through vessels to body


connective tissue with fluid matrix called plasma in which blood cells are suspended

Open Circulatory System

circulatory system in which blood is pumped through open ended vessels and bathes tissues and organs directly

Closed Circulatory System

circulatory system in which blood is confined to vessels and is separate from intestine fluid

Cardiovascular System

closed circulatory system with a heart and branching network of arteries, capillaries and veins


vessel that carries blood away from heart to rest of body


vessel that returns blood to the heart


blood vessel that conveys blood between an arteriole and a venule, enables exchange of nutrients


heart chamber that receives blood from the veins


heart chamber that pumps blood out of the heart


vessel that conveys blood between an artery and capillary bed

Capillary Beds

network of capillaries that infiltrate every organ and tissue in body


vessel that conveys blood between capillary bed and vein

Pulmonary Circuit

one of two main blood circuits in vertebrates, conveys blood between heart and lungs

Systemic Circuit

one of two main blood circuits in vertebrates, conveys blood between heart and rest of body

Pulmonary Arteries

large blood vessel that conveys blood from heart to lung

Pulmonary Veins

blood vessel that conveys blood from a lung to the heart


artery that conveys blood directly from left ventricle to other arteries

Cardiac Cycle

alternating contractions and relaxations of the heart

Heart Rate

frequency of heart contraction

Heart Murmur

hissing sound that most often results from blood squirting backwards through leaky valve in heart

SA Node

pacemaker of the heart, located in right wall of atrium, sets rate and timing at which cardiac muscles contract

AV Node

region of specialized heart muscle tissue between left and right atria where electrical impulses are delayed for about 0.1 second before spreading to both ventricles and causing them to cotnract

Heart Attack

damage or death of cardiac muscle cells and the resulting failure of the heart to deliver enough blood to the body

Cardiovascular Disease

diseases of the heart and blood vessels


death of nervous tissue in the brain, usually resulting from rupture or blockage of arteries in the head

Blood Pressure

force that exerts blood against the walls of blood vessels


rhythmic stretching of arteries caused by pressure of blood during contraction of ventricles


abnormally high blood pressure, above 140/90

Red Blood Cells

erthrocyte, blood cell containing hemoglobin which transports O2

White Blood Cells

leukocyte, blood cell that functions in defending body against infections or cancer


liquid matrix of blood in which blood cells are suspended


pinched-off cytoplasmic fragment of a bone marrow cell, circulates blood


white blood cell that engulfs bacteria, foreign proteins and remains of dead body cells


condition in which an abnormally low amount of hemoglobin or low number of red blood cells results in body cells receiving not enough oxygen

Erythropoietin (EPO)

hormone that stimulates production of red blood cells

Stem Cells

unspecialized cell that can divide to produce an identical daughter cell and a more specialized daughter cell, which undergoes differentiation


type of cancer of the blood-forming tissues, characterized by an excessive production of white blood cells

Nervous System

organ system that forms a communication and coordination network between all parts of an animal's body


nerve cell functional unit of nervous system, carrying signals

Central Nervous System

integration and command center of the nervous system, the brain and spinal cord

Peripheral Nervous System

network of nerves and ganglia carrying signals into and out of central nervous system


cable-like bundle of neuron fibers tightly wrapped in connective tissue


cluster of nerve cell bodies in a central nervous system

Sensory Input

conduction of signals from sensory receptors to processing centers in central nervous system


interpretation of sensory signals within neutral processing centers of the central nervous system

Motor Output

conduction of signals from a processing center in a central nervous system to effector cells

Effector Cells

cell capable of carrying out some action in response to a command from the nervous system


automatic reaction to a stimulus, mediated by spinal cord or lower brain

Sensory Neurons

nerve cell that receives info from sensory receptors and conveys the in the central nervous system


nerve cell, entirely within central nervous system, that integrates sensory signals and may relay command signals to motor neurons

Motor Neurons

nerve cell that conveys command signals from the central nervous system to effector cells

Cell Body

part of a cell, such as a neuron, that houses the nucleus


neuron fiber that conveys signals from its tip inward, toward the rest of the neuron


neuron fiber that conducts signals to another neuron or to an effector cell


supporting cell that is essential for the structural integrity and normal functioning of the nervous system

Myelin Sheath

series of cells, each wound around and thus insulating, the axon and nerve cell in vertebrates


junction between two neurons, or between a neuron and effector cell, electrical or chemical signals are relayed from one cell to the other

Membrane Potential

charge difference between a cell's cytoplasm to the differential distribution of ions

Resting Potential

voltage across the plasma membrane of a resting neuron


factor that triggers sensory transduction in central nervous system

Action Potential

self-propogating change in voltage across plasma membrane of neuron

Synaptic Cleft

in chemical synapse, narrow gap separating synaptic terminal of transmitting neuron from receiving neuron or effector cell


chemical transmitter that carries info from a transmitting neuron to a receiving cell


presence of central nervous system distinct from peripheral nervous system


concentration of nervous system at anterior (head) end

Spinal Cord

dorsal hollow nerve cord in vertebrates, with brain makes up central nervous system


part of central nervous system involved in regulating and controlling bodily activity and interpreting info from senses transmitted through nervous system

Blood-Brain Barrier

system of capillaries that restricts passage of most substances into the brain, thereby preventing large fluctuations in brain's environment


heart chamber that pumps blood out of heart

Central Canal

narrow cavity in center of spinal cord that is continuous with fluid-filled ventricles from brain

Cerebrospinal Fluid

blood-derived fluid that surrounds, protects against infection, nourishes and cushions the brain and spinal cord


layers of connective tissue that enwrap and protect brain and spinal cord

White Matter

tracts of axons within central nervous system

Gray Matter

regions of dendrites and clusters of nerve cell bodies within central nervous system

Cranial Nerves

nerve that leaves the brain and innervates an organ of the head or upper body

Spinal Nerves

in vertebrate peripheral nervous system, nerve that carries signals to or from spinal cord

Somatic Nervous System

component of vertebrate peripheral nervous system that carries signals to and from skeletal muscles

Autonomic Nervous System

component of vertebrate peripheral nervous system that regulates internal environment, made of sympathetic and parasympathetic divisions

Parasympathetic Division

set of neurons in autonomic nervous system that generally promotes body activities that gain and conserve energy, such as digestion

Sympathetic Division

set of neurons in autonomic nervous system that generally prepares body for energy-consuming activities

Enteric Division

part of autonomic nervous system consisting of complex networks of neurons in the digestive tract, pancreas and gallbladder


develops into thalamus, hypothalamus and cerebrum


develops into sensory integrating and relay centers that send sensory info to the cerebrum


develops into medulla oblongata, pons and cerebellum


largest, most sophisticated and most dominant part of vertebrate forebrain, made up of left and right cerebral hemispheres

Medulla Oblongata

part of vertebrate hindbrain continuous with spinal cord, passes data between spinal cord and forebrain and controls autonomic functions


part of vertebrate hindbrain that functions with medulla oblongata in passing data between spinal cord and forebrain and in controlling autonomic functions


functional unit of vertebrate brain, composed of midbrain, medulla oblongata and pons, serves as sensory filter, selecting which info reaches higher brain centers


part of vertebrate hindbrain, planning center that interacts closely with cerebrum and in coordinating body movement


integrating and relay center of the vertebrate forebrain, sorts and relays selected info to specific areas in cerebral cortex

Cerebral Hemispheres

right or left half of the vertebrate cerebrum

Corpus Callosum

thick band of nerve fibers that connect the right and left cerebral hemispheres, enabling them to process info together

Cerebral Cortex

contains integrating centers for higher brain functions such as reasoning and speech


phenomenon in which two hemispheres of brain become specialized for different functions

Limbic System

functional unit of several integrating and relay centers located in human forebrain, interacts with cerebral cortex in creating emotion and storing memory


ability to store and retrieve info


integrative center of the cerebrum, part of limbic system that labels info to be remembered


integrative center of cerebrum, part of limbic system that plays a central role in memory and learning

Short Term Memory

ability to hold info, anticipations or goals for a time and release them if they become irrelevant

Long Term Memory

ability to hold, associate and recall info over one's life

Parkinson's Disease

mental disorder caused by progressive brain disease and characterized by difficulty in initiating movements


mental disturbance characterized by psychotic episodes in which patients lose ability to distinguish reality from hallucinations

Bipolar Disorder

depressive mental illness characterized by mood swings


assemblage of all organisms living together and potentially interacting in an area

Interspecific Interaction

relationships among individuals of different species in a community

Interspecific Competition

competition between individuals or populations of two or more species requiring a limited source


interspecific relationship in which both partners benefit


evolutionary change in which adaptations in one species act as a selective force on a second species, mutual influence on evolution of two different interacting species


organism that makes organic food molecules from CO2, H2O and other inorganic raw materials

Primary Consumers

organism that eats plants or algae

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