The Nervous System

Biology II

Membranes located between bone and soft tissues of the nervous system

Meninges

Outermost layer, blood vessels, nerves

Dura Mater

No blood vessels, located between inner and outer layers of meninges

Arachnoid Mater

Contains many nerves and blood vessels to nourish cells of brain and spinal cord

Pia Mater

Between arachnoid and pia maters

Cerebrospinal Fluid

Passes from brain down through the vertebral canal

Spinal Column

The spinal column has ____ segments, each with a pair of spinal nerves

31

Supplies nerves to upper limbs (neck)

Cervical Enlargement

Supplies nerves to the lower limbs (lower back)

Lumber Enlargement

What is the spinal columns function?

Conducting nerve impulses, serves as a center for spinal reflexes

Carry sensory info to the brain

Ascending Tracts

Carry motor impulses from the brain to the muscles

Descending Tracts

Reflex arcs pass through the spinal cord

Spinal Reflexes

What are the 3 major parts of the brain?

Cerebrum, Cerebellum, Brain Stem

Largest, sensory and motor function, memory and reasoning

Cerebrum

Coordinate voluntary muscles

Cerebellum

Regulate visceral functions

Brain Stem

Function of left hemisphere

Logic, Language, Math

Function of the Right hemisphere

Creativity

Left and right hemispheres are separated by the _______ but also connects them together

Corpus Callosum

The wrinkles and grooves of the cerebrum

Convolutions

What is the deep groove, shallow groove, and bump called?

-Fissure
-Sulcus
-Gyrus

Separate right and left sides

Longitudinal Fissure

Separate the temporal and parietal lobes

Lateral Fissure

Separates occipital and cerebellum

Transverse Fissure

Emotion, planning, language, movement

Frontal Lobe

Math

Parietal Lobe

Memories, auditory, language

Temporal Lobe

Vision

Occipital Lobe

Outermost portion of the cerebrum

Cerebral Cortex

Fluid filled cavities, contain cerebrospinal fluid

Ventricles

Clear fluid that protects and supports the brain

Cerebrospinal Fluid

Movment

Motor Region

Coming together with motor and sensory

Association Region

Sensations

Sensory Region

What are the two parts of the dienchephalon?

Thalamus and Hypothalamus

Relay station

Thalamus

Attaches to the pituitary, regulates hormones, heart rate, blood pressure, hunger

Hypothalamus

Optic nerves cross over each other

Optic Tract/Chiasma

Eye movements, visual reflexes

Midbrain

Heart, respiration, blood pressure (involuntary activites)

Medulla

Relay sensory information & regulates breathing and sleep

Pons

"Master gland" regulates hormones

Pituitary Gland

Emotions (made up of amygdala and hippocampus)

Limbic System

Memories

Hippocampus

Events and experiences

Episodic Memory

Skills and tasks

Procedural Memory

Facts and concepts

Semantic Memory

Temporary storage of information, learning, and reasoning

Working Memory

The worm-like ridges on the surface of the brain are called

Gyrus

The thin, web-like membrane between the outer and inner layer of meninges is called the

Arachnoid Mater

The right side of your brain controls the _____ side of your body

Left

The _____ enlargement of the spinal cord supplies nerves to the lower limbs, whereas the _____ enlargement supplies nerves to the shoulders and arms.

Lumber - Cervical

The innermost layer of meninges that supplies blood vessels to the brain called the

Pia Mater

The _____ fissure separates the two hemispheres

Longitudinal

_____ tracts within the spinal cord carry motor impulses to the muscles

Descending

The ____ ____ connects the two hemispheres of the brain

Corpus Callosum

The ____ is the major part of the brain that controls higher mental activities, such as learning and making decisions

Cerebrum

_____ tracts within within the spinal cord carry sensory impulses to the brain

Ascending

The outermost of the three meninges is the

Dura Mater

The fluid filled cavities within our brains are called

Ventricles

The brain and spinal cord are surrounded (and float within)

Cerebrospinal Fluid

The brain ____ consisted of the midbrain, pons, and medulla oblongata

Stem

The ____ system controls emotional experiences

Limbic

The _____ _____ is responsible for the regulation of the body, such as heart rate, body temperature, and blood pressure

Medulla Obongata

The part of the brain that plays a major role in memory is the ______

Hippocampus

The master gland of the endocrine system dealing with hormones is the ________

Pituitary Gland

Part of the diencephalon, controls basic functions such as body temperature, and hunger

Hypothalamus

The _____ is the part of the brain that controls the coordination, balance and equilibrium

Cerebellum

The nervous system includes...

Brain, spinal cord, nerves

Overall function

coordinate the body's systems by receiving and sending information; maintaining homeostasis

Sensory

receives information

Integrative

determines where information is sent

Motor

responds to signals

Two divisions of the nervous system

CNS & PNS

CNS

brain and spinal cord

PNS

nerves (31 pairs of spinal - 12 pairs of cranial)

Somatic Nervous System

-skeletal
-voluntary

Autonomic Nervous System

-smooth muscles
-glands
-involuntary

Autonomic nervous system 2 branches

-Parasympathetic (rest and digest)
-Sympathetic (fight or flight)

Neurons

masses of nerve cells that transmit info
*functional unit of the nervous system

Cell body

contains the nucleus and other cell organelles

Dendrites

shorter, more numerous, receives information

Axons

single long fibers, conducts information away from the cell

Chromatophilic substance (rough er)

transport system

Myelin

insulation surrounding axons (myelin shealth)

Nodes of Ranvier

gaps in the insulation

Neuroglial Cells

support for neurons

Microglial cells

immune function; digest debris, kills bacteria

Oligodendrocytes

make myelin shealth that provides insulation around the axons in the CNS

Astrocyte

connect blood vessels to neurons

Ependymal cells

forms membranes around tissue

Schwann cells

forms the insulating myelin shealths around nerouns in the PNS

Myelin shealths

insulate axons

As neurons lose their myelin...

the nerves are unable to send or receive signals

Myelinated axons

white matter

Unmyelinated axons

grey matter

lesions are evidence of the nerve cell damage in the

brain or spinal cord

nerve impulses

weak electric current, like a wave

Nerve Impulse

1. neuron membrane maintains resting position
2. threshold stimulus is received
3. sodium channels open
4. sodium ions diffuse inward, depolarizing the membrane
5. potassium channels open
6. potassium ions diffuse outward, repolarizing the membrane
7. the resulting action potential causes a local bioelectral current that stimulates the membrane
8. Wave of action potentials travel the length of the axon as a nerve impluse