PSIO 201 - Block 4

Maintains homeostasis

Rapidly transmits information

Responsible for voluntary and involuntary movement, perception, behavior, memory, and more

What does the nervous system do?

Neural tissue made up of neurons and neuroglia

What is the nervous system composed of?

Sensory information

Integration

Motor function

How does information flow in the nervous system?

Input, information goes into the brain and spinal cord via cranial and spinal nerves

What is sensory information?

Proccessing, integrates sensory information by analyzing and storing it

What is integration?

Output, information from the brain and spinal cord is sent out to effectors (muscles or glands)

What is motor function?

Central Nervous System (CNS) and Peripheral Nervous System (PNS)

What are the two parts of the nervous system?

Brain and spinal cord

What does the central nervous system consist of?

Primarily cranial and spinal nerves, essentially all nervous tissue outside of the CNS

What does the peripheral nervous system consist of?

Sensory division and motor division

What are the components of the peripheral nervous system?

Sent to the CNS for processing and interpreting

Where are sensory inputs sent from the PNS and why does this occur?

Somatic nervous system and autonomic nervous system

What are the components of the motor division of the PNS?

Controls voluntary movement of skeletal muscle

What does the somatic nervous system do?

Sympathetic nervous system

Parasympathetic nervous system

Enteric nervous system

What are the divisions of the autonomic nervous system?

Fight or flight

What is the sympathetic nervous system?

Rest and digest

What is the parasympathetic nervous system?

Controls gastrointestinal functions

What is the role of the enteric nervous system?

Neurons and neuroglia

What are the two cell types of nervous tissue?

Excitable cells that transmit action potentials within nervous tisse

What are neurons?

Have many functions including support, protection, and nourishment of neurons

What are the functions of neuroglia?

Glial cells

What is another name for neuroglia?

Largest part of a typical neuron; contains the nucleus and receives information

What is the cell body?

Branchlike parts of a neuron that are specialized to receive information

What are dendrites?

transmits information to other neurons, muscles, or glands

What does an axon do?

These are the enlarged ends of the axon terminals.

Neurotransmitters are stored and released from here to transmit the impulse from this neuron to the next structure.

What is a synaptic end bulb and what does it do?

Branches at the end of the axon

What are axon terminals?

Around 200 billion

How many neurons are found in the adult human body?

Side branches of the axon

What are axon collaterals?

From the dendrites towards the synaptic end bulb

What way do electrical signals flow through a neuron?

Fatty substance that helps insulate neurons and speeds the transmission of nerve impulses

What is myelin?

Afferent neurons (Sensory neurons)

Interneurons (Integrative neurons )

Efferent neurons (Motor neurons)

What are the three functional classifications of neurons?

Information goes to the brain and spinal cord via cranial and spinal nerves

What do afferent neurons do?

Mylenated axon

What is an axon surrounded by myelin called?

Integrates sensory information by analyzing and storing it

What do interneurons do?

Peripheral nervous system

Where are afferent neurons located?

Brain and spinal cord

Where are interneurons located?

Information from the brain and spinal cord is sent out to muscles or glands (Effectors)

What are efferent neurons?

Carry signals from CNS to effectors

Where are efferent neurons located?

Afferent neurons

What is label 4?

Interneurons

What is label 5?

Efferent neurons

What is label 6?

Unipolar

What is the structural classification of this neuron?

Multipolar

What is the structural classification of this neuron?

Bipolar

What is the structural classification of this neuron?

Unipolar or bipolar

What type of structural neurons are sensory neurons in humans?

Multipolar

What type of structural neurons are interneurons and efferent neurons in humans?

Six

How many types of neuroglia are there?

Astrocytes

Oligodendrocytes

Microglia

Ependymal cells

What are the four types of neuroglia found in the CNS?

Maintain environment around neurons

Keep neurons in place

Form the blood-brain barrier

What do astrocytes do?

The project foot processes which wrap around capillaries in the brain to form the blood brain barrier

What do astrocytes project and what do they do?

Cell processes form myelin sheaths around axons in the CNS to increase the speed of transmission of action potentials

What do oligodendrocytes do?

Engulf invading microbes, debris, and necrotic tissue

What do microglia do?

Line ventricles of the brain and the central canal of the spinal cord

Forms and circulates cerebrospinal fluid from blood plasma

What do ependymal cells do?

Sattelite cells

Schwann cells

What are the two types of neuroglia found in the PNS?

Cover sensory neuron cell bodies

Maintains neuron environment

What do satellite cells do?

Entire cell forms myelin sheath around axons in the PNS to increase the speed of transmission of action potentials

What do Schwann cells do?

Axon

What is label 5?

Cell body

What is label 7?

Process

What is label 1?

Satellite cells

What is label 2?

Nucleus

What is label 3?

Cell body

What is label 4?

Axon terminal

What is label 1?

Axon

What is label 5?

Schwann cell

What is label 2?

Axon collateral

What is label 4?

Dendrites

What is label 6?

Cell body

What is label 7?

Myelin sheath

What is label 10?

Axon

What is label 3?

Cell body

What is label 5?

Nucleus

What is label 6?

Dendrites

What is label 7?

Sattelite cell

What is label 5?

Schwann cell

What is label 6?

Oligodendrocyte

What is label 1?

Microglial cell

What is label 2?

Astrocytes

What is label 3?

Ependymal cell

What is label 4?

Maintains a stable environment for the brain

What does the blood brain barrier (BBB) do?

Foreign substances in the blood

Hormones and neurontransmitters that are traveling through the blood to the rest of the body

What does the blood brain barrier protect the brain from?

Dendrites

What is label 6?

Injecting mice with a blue dye that appeared everywhere but the brain

How was the BBB discovered?

Heroin
Alcohol
Nicotine
THC (Marijuana)

What are some narcotic/controlled substances that can pass the BBB?

Pituitary gland

Area postrema

What are some areas of the brain with a weaker BBB?

Induces vomiting if toxins are sensed in blood

What is the function of the area postrema?

Least permeable capillaries in the body

What is unique about capilaries in the brain?

Astrocytes extend foot processes around capillary endothelial cells

Why are capillaries in the brain less permeable?

Cells that line the walls around blood capillaries

What are endothelial cells?

Maintain tight junctions between one another

How do endothelial cells make the capillaries in the brain less permeable?

Oxygen, carbon dioxide, and small lipid-soluble molecules

Large lipid-soluble molecules and negatively charged molecules can diffuse slowly

What can cross the BBB?

Transported by channels and carriers

How do glucose and amino acids get across the BBB?

They are small lipid-soluble molecules

Why do antidepressants move across the BBB?

Nanodiamonds

What is a new technique being used to transport things across the BBB in mice?

Connective tissue coverings that surround the brain

What are cranial meninges?

Protect underlying neural tissues

Anchor the brain in the cranial cavity

What are the functions of meninges?

Inflammation of the meninges due to a bacterial or viral infection

Leads to swelling and stretching which can cause severe headaches, nausau and even death

What is meningitis?

IV antibiotics

How is bacterial meningitis treated?

Hearing loss and long term brain damage

What are some consequences of meningitis?

Mild cases typically resolve on their own, some antiviral medications can be used, vaccines exist against most common types

How can viral meningitis be treated?