levels of organization in the body
cells, tissues, organs, organ systems
basic unit of structure and function in a living thing
forms the outside boundary of a cell
the control center that directs the cells activities and contains the information that determines the cells form and function
the material within a cell apart from the nucleus
a group of similar cells that perform the same function
can contract, or shorten
directs and controls the process
provides support for your body and connects all its parts
the surfaces of your body, inside and out, are covered by this
a structure that is composed of different kinds of tissues
examples of organs
stomach, heart, brain, lungs
a group of organs that work together to perform a major function
transports materials to and from cells
controls many body processes by means of chemicals
enables movement of the body and internal organs
breaks down food and absorbs nutrients
detects information from the environment and controls body functions
supports and protects the body
takes in oxygen and eliminates carbon dioxide
all the systems in the body work together to maintain this
homeostasis is the process by which...
an organisms internal environment is kept stable in spite of changes in the external environment
the reaction of your body to potentially threatening, challenging, or disturbing events
made up of all the bones in your body
five major functions of the skeleton
shape and support, enables you to move, protects your organs, produces blood cells, and stores minerals and other materials your body needs
the 26 small bones that make up your backbone
a place in the body where two bones come together
what do joints do?
joints allow bones to move in different ways
what do moveable joints do?
they allow the body to make a wide range of movements
bone to bone
more flexible than bone, a connective tissue
hard and dense, but not solid. beneath the outer membrane
porous. inside the femurs compact bone
connective tissue located in the spaces in many bones
red bone marrow
produces most of the bodys blood cells
stores fat that can serve as an energy reserve
why are bones hard?
they contain calcium and phosphorus
a condition in which the body's bones become weak and break easily
what are common skeletal injuries?
fractures, dislocations, sprains
a break in a bone
occurs when the end of a bone comes out of its joints
occurs when ligaments are stretched too far and tear in places
a form of energy that travels in waves, like the light your eyes can see
what are two ways to identify injuries?
x-rays and MRI
a method for taking clear images of both bones and soft tissues of the body
what are 3 ways to treat injuries?
cast, surgical procedures, arthroscopy
a disease of the joints that makes movement painful
slim, tube-shaped instrument to make a small incision
muscles not under your conscious control
examples of involuntary muscles
breathing, digesting food
muscles that are under your conscious control
examples of voluntary muscles
smiling, turning a page in a book, getting out of your chair
what are three types of muscle tissue?
skeletal muscle, smooth muscle, cardiac muscle
attached to the bones of your skeleton and provide the force that moves your bones
a strong connective tissue that attaches muscle to bone
skeletal muscle cells appear banded
the inside of many internal organs, involuntary muscles
tissue found only in your heart, involuntary muscles
muscles work in pairs because
when one muscle contracts, the other muscle in the pair relaxes it to its original length
what does the skin protect you from?
injury, infection, water loss
what does the skin help?
regulate body temperature, eliminate wastes, gather information about the environment, produce vitamin D
what are the two main layers of skin?
the outer layer of skin, thin
the inner layer of skin
a colored substance that gives skin its color, cells deep in the epidermis produce this
sweat glands produce perspiration, which reaches the surface through openings
strands of hair grow within the dermis in structures called...
what are three ways to keep your skin healthy?
healthy diet, keep skin clean and dry, limit exposure to the sun
a disease in which some cells in the body divide uncontrollably