Lecture 21: Nervous System (Part 2)

What makes up nervous tissue?

neurons and glial cells

What is the function of neurons?

transmits nervous signals throughout the body

What is the function of glial cells?

cells that support the neuron and have different roles to help support the neuron

Describe the structure of a neuron?

Consist of perikaryon which contains the nucleus and the extensions are the neuron processes (dendrites and axons)

What are the three types of neurons?

sensory neurons, interneurons, and motor neurons

What is the function of sensory neuron?

they transmit information about the bodies external and internal environment to do CNS

What is the function of interneurons?

found within the CNS; functionto integrate sensory input

What is the function of motor neurons?

extends out of the CNS; functions to transmit information to various target organs or effectors

What are the two types of ways neurons can communicate with each other?

Electrical signals and chemical signals

What is electrical signals?

transmit signals along the axons of neuron and long distances;

What is chemical signals?

transmitted along synapse or synaptic clips and very short distances

What is a synapse?

small space between a pre synaptic cell and post synaptic cell

What is resting potential?

the difference in electrical charge between the inside and outside of a neuron cell (stays around -60 to -70 mV)

What are the three factors that maintain the resting potential of neurons?

ungated sodium and potassium channels (more K⁺ channels than Na⁺ this will keep the inside negative and the outside positive; outside of the cell there is increased concentration of Na⁺ than K⁺ while inside the cell there is increased concentration K⁺ than Na⁺), large negatively charged molecules, and sodium potassium pump (moves Na⁺ ions out of the cells and K⁺ ions into the cell; 3 Na⁺ out and 2 K⁺ in)

What is the sodium potassium pump?