Unit 3: Homeostasis - All terms -

homeostasis

the process where organ systems work to maintain (keep) a stable internal environment.

negative feedback

a response to a stimulus that keeps a variable close to a set value (it "shuts off" or "turns on" a system when it varies from a set value)

stimulus (plural: stimuli)

something that triggers a behavior or causes a reaction in an organism.

receptor

a cell or group of cells that receives stimuli

signal

a message that is sent between cells

response

an action or message as a result of a signal

diffusion

the movement of molecules from an area of high concentration of the molecules to an area with a lower concentration

membrane

a thin sheet of tissue or layer of cells acting as a boundary, lining, or partition in an organism.

concentration gradient

The difference in the concentrations of molecules in two areas

equilibrium

the process where organ systems work to maintain (keep) a stable internal environment

Cell

basic unit of structure and function of living things.

Specialized Cell

a cell that has a specific shape (structure) and function

Tissue

group of specialized cells of the same kind that work together to perform the same function.

Organ

structure composed of two or more types of tissues that work together to perform a particular function.

Organ System

group of organs that work together to perform a particular function for the organism.

Nervous System

organ system that consists of the brain, spinal cord, and a complex network of nerves that carries electrical messages throughout the body.

Neuron

a nerve cell, is the basic unit of the nervous system and is responsible for receiving, processing, and transmitting information through the body

circulatory system

a system made up of blood vessels that carry blood away from and towards the heart.

circuit

a loop / track within your body that has a specific function

artery

carries blood away from the heart to capillaries

capillary

a very fine (thin) blood vessel that allows the exchange of molecules between tissues and blood.

vein

carries blood from capillaries back to your heart

systemic circuit

the part of the circulatory system that carries blood between the heart and body

pulmonary circuit

the part of the circulatory system that carries blood between the heart and lungs

diffusion

the movement of anything generally from a region of higher concentration to a region of lower concentration.

atrium (plural = atria)

heart chamber that receives blood into the heart and drives it into a ventricle

ventricle

heart chamber that pumps blood out of the heart and into the circulatory system

valve

a type of flap that act as one-way inlets for blood coming into a ventricle and one-way outlets for blood leaving a ventricle.

sweat gland

gland in the skin that produces the salty fluid called sweat, which excretes (gets rid of) wastes and helps cool the body

radiation (of heat)

heat energy is transferred through electromagnetic waves (for instance from your skin to the environment)

evaporation

the process where a liquid turns into a vapor (gas).; this process requires heat energy

evaporative cooling

reduction in temperature resulting from the evaporation of a liquid

dilate

to relax or make bigger/wider

constrict

to squeeze or make smaller/narrower

blood vessel

a tubular (pipe-shaped) structure carrying blood that connects the heart to the rest of your body (e.g. a vein, artery, or capillary)

blood

carries gases, nutrients and heat to and from cells in vessels called capillaries