Biology - Nervous System and Musculoskeletal system

Function of Nervous System

Controls actions of the body by communicating via neurons transmitting signals, and coordinates movement

• responds to stimuli by electrochemical messages relayed to and from brain OR by hormones, chemical reactions carried by blood

2 division of Nervous System

• Central Nervous System

  • brain+spinal cord

  • intergates and processes info sent by nerves

• Peripheral Nervous System

  • Sensory neurons carry signals from sensory receptors to CNS

  • Motor neurons carry signals from CNS to effectors (muscles + glands)

Neurons

Basic structural and functional unit of nervous system

• Individual cell that quickle carries electrical impulses from one point of body to another

  • respond to stimuli (chemical and physical)

  • conduct electrochemical symbols

  • release chemicals that regulate body processes

Glial Cells

Cells that support neurons and provide supporting framework to nervous system tissue

• nourish, remove waste, protect against infection

Nerves

Individual neurons organized into tissues

Neuron Structure

• Dendrites = convert chemical info into electrical signals (from other neurons/receptors)

• Axon = Transmit electrical signals to terminal regions for communication (w/ other neurons/effectors)

• Soma = Cell body, contains nucleus and organelles where essential metabolic processes occur for cell survival

• Myelin sheath

Stimulus Response

Basic Pathway for a nerve impulse

1) Receptor detects change in internal/external environment, a stimulus

2) Receptor transforms stimuli into electrical nerve impulse

3) Neurons transmit impulses to CNS where decision making occurs

4) CNS selects a conscious/unconscious response, and neurons transmit signals to effectors

5) Effectors (organs, muscles/glands) produce response and there is a change in the organism from detection of this stimulus

Musculoskeletal System Function

Allows for movement, gives support and protection, through collaboration of the nervous, muscular and skeletal system

3 systems involved w/ musculoskeletal system

• Nervous - Motor neurons send signals to muscles from CNS, which cause them to contract and create movement. Also control timing of contractions.

• Muscular - Muscles deliver required force to move one bon in relation to another

• Skeletal - Consist of bones that act as levers and provide structure for muscles to pull

Neuron Diagram

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