human body system

• Muscles & bones


  Work together
• Why muscles & bones work together

  To enable movement
• Functions of the skeletal system

  • Provides shape & support
  • Helps you move
  • Protects organs
  • Produces blood cells
  • Stores certain materials
• Skeletal system protects internal organs


  • Skull protects the brain
  • Ribs protect the heart & lungs
  • Vertebrae protect the spinal cord
  • Femur produces blood cells in the leg
  • Humerus produces blood cells in the arm
• Organs of the skeletal system

  • Bones
  • Cartilage
  • Ligaments
• Cartilage


  Connective tissue that is more flexible than bone
• Ligaments


  Hold bones together to form joints
• Types of bone marrow

  • Red marrow produces the body's blood cells
  • Yellow marrow stores fat (energy reserve)
• Functions of the muscular system


  • Helps the body move
  • Moves food through the digestive system
  • Keeps the heart beating
• Involuntary muscle


  Muscles not under your conscious control
• Examples of involuntary muscles

  • Muscles used for breathing & digesting food
• Voluntary muscles


  Muscles that are under your conscious control
• Examples of voluntary muscles

  • Smiling
  • Turning the pages in a book
  • Walking to class
• 3 types of muscle tissue

  • Skeletal
  • Smooth
  • Cardiac
• Skeletal muscle


  • Attached to bones & move bones using tendons
  • Connective tissue attaching muscles to bones
  • Striated, or banded
  • Voluntary
• Smooth muscle

  • Inside many internal organs
  • Involuntary
• Cardiac muscle


  • Found only in the heart
  • Involuntary
  • Never gets tired (unlike skeletal muscles)
• How muscles work

  1. Muscles move by contracting, or becoming shorter

  2. Must work in pairs - one contracts, the other returns to its original length
• Functions of the integumentary system (skin)

  • Covers and protects the body to prevent water loss and keep out foreign particles
  • Keeps you in touch with the environment (nerve endings)
  • Regulates your body temperature
  • Gets rid of wastes (sweat/perspiration)
• Layers of the skin

  • Epidermis
  • Dermis
• Epidermis


  • Outermost layer
  • No nerves or blood vessels
  • Surface is made of dead cells (provide protection)
• Dermis


  • Lower layer of the skin
  • Contains nerves, blood vessels, sweat glands, hairs & oil glands
• Describe how the integumentary system works with one other system to perform a specific function
• Functions of the nervous system

  • Receives information about what is happening inside & outside of the body
  • Directs the way your body responds to this information
  • Helps maintain homeostasis
• Organs of the nervous system

  • Brain
  • Nerves (neurons – nerve cells)
  • Spinal Cord
• Parts of the central nervous system


  • Brain
  • Cerebrum
  • Cerebellum
  • Brainstem (medulla)
  • Spinal cord
• Cerebrum


  • Interprets input from the senses
  • Controls movement of skeletal muscles
  • Complex mental processes (learning)
• Cerebellum


  Coordinates muscle actions & balance
• Brainstem (medulla)


  Controls involuntary actions (ex: breathing)
• Neurons


  Nerve cell that is specialized to transfer messages in the form of fast-moving electrical energy
• Path of nerve impulse


  1. Sensory neuron

  2. Spinal cord

  3. Brain

  4. Spinal cord

  5. Motor neuron
• Explain how your nervous system might work with your muscular system when you touch a hot pan on the stove
• Why the body needs oxygen
• Functions of the respiratory system


  • Moves oxygen from the outside environment into the body
  • Removes carbon dioxide and water from the body
• Path of air into the body

  1. Nose

  2. Pharynx

  3. Trachea

  4. Bronchi

  5. Alveoli
• Diaphragm


  Large dome-shaped muscle used in breathing
• Describe how the respiratory system works with one other system to perform a specific function
• Circulatory system (aka Cardiovascular System)


  Carries needed substances to cells and carries wastes away from cells
• Organs of the circulatory system


  • Heart
  • Arteries
  • Capillaries
  • Veins
• Heart


  Hollow, muscular organ that pumps blood throughout the body