The Neuron The information processing and information-transmitting element of the nervous system.

Different neuron types

Sensory neurons activated by sensory input from the environment Ex. touching a hot surface with your fingertips, the sensory neurons will be sending info to the rest of the nervous system The inputs that activate sensory neurons can be physical or chemical physical input can be things like sound, touch, heat, or light. chemical input comes from taste or smell, which neurons then send to the brain

Interneurons Interneurons are the ones in between - they connect spinal motor and sensory neurons. transfer signals between sensory and motor neurons communicate with each other, forming circuits of various complexity

Motor Neurons Motor neurons of the spinal cord are part of the central nervous system (CNS) and connect to muscles, glands and organs throughout the body They transmit impulses from the spinal cord to skeletal and smooth muscles (such as those in your stomach), and so directly control all of our muscle movements.

Reflexes A simple spinal reflex has a single sensory neuron and a single motor neuron that communicate through an interneuron

Types of Neurons in a nutshell Sensory Neurons (afferent neurons) take in info from the outside world and send it to the brain and spinal cord Motor Neurons (efferent neurons) bring messages to the muscles from the brain and spinal cord Interneurons communicate between neurons

Afferent Efferent

https://www. youtube. com/watch https://www.youtube.com/watch?v=FVo04B0_5R4&index=2&list=PLqTetbgey 0aekpYHoIPKssY94U-OBMeNE (begin at 7:25)

Glial cells Astrocyte (Astroglia): Star-shaped cells that provide physical and nutritional support for neurons: 1) clean up brain "debris"; 2) transport nutrients to neurons; 3) hold neurons in place; 4) digest parts of dead neurons; 5) regulate content of extracellular space Microglia: Like astrocytes, microglia digest parts of dead neurons. Oligodendroglia: Provide the insulation (myelin) to neurons in the central nervous system. Satellite Cells: Physical support to neurons in the peripheral nervous system. Schwann Cells: Provide the insulation (myelin) to neurons in the peripheral nervous system.