Brain

Major Lobes of the Brain

Frontal- thinking/ problem solving

Parietal- perception, numbers

Occipital- Visual

Temporal- audiitory and olfactory, deep and complex memories

Cerebellum

coordinating movement and balance, processing information for motor control

Hypothalamus

Under Thalamus

Autonomic nervous system center, regulates body temp, controls water balance, regulates metabolism, part of limbic system (emotions, tirst, hunger, pain etc)

Diencephalon

Parts: Thalamus Hypothalamus, Epithalamus

Sits on top of brian stem

Enclosed by the cerebral hemisphere

Thalamus

Surrounds third ventricle

Relay station for sensoy impulses

Transfer impulses to the corret par of the cortex for localization and interpretation

Epithalamus

Forms the roof of the 3rd ventricle

Houses the pineal body (endocrine gland)

Includes the choroid plexus

Forms cerbralspinal fluid

Brain Stem

Parts: Midbrain, Pons, Medulla oblongata

Controls breathing and blood pressure

Midbrain

Reflex centers for vision and hearing

Composed of tracts of nerve fibers

Has two buldging fiber tracts- cerebral peduncles

Has four rounded protrusions-corpora quadrigemina

Pons

Nuclei involved in the control of breathing

composed of fiber tracts

buldging center part of brain stem

Medulla Oblogata

lowest part of brain stem, merges into spinal cord, fiber tracts

Controls heart rate, blood pressure, breathing, swallowing, vomitting

Bipolar neurons

One axon and one dendrite

Eyes and nose

Multipolar neurons

Motor and association

Many extons

brain and spinal cord

Dendrite

conduct impulses toward cell body

Axon

conduct impulses away from the cell body

only one axon- hill ock

Myelin Sheath

Nerve fiber covering- protects, insulates, increases transmission rate of impulses

Schawnn cells make it

Nodes of ranvier cap it

Axon terminal

contain vesicles with neurotransmitters

sepperate from the next neuron by a gap

synaptic cleft

synapse- junction between nerve

Epineurium

The protective sheath surrounding a nerve fascicle, consisting of several layers of flat cells that provide structural support and maintain the integrity of nerve fascicles.

Endoneurium

A delicate layer of connective tissue that surrounds each individual nerve fiber, providing support and protection.

Corpus callosum

connect the left and right hemispheres of your brain

Afferent vs efferent

Sensory (afferent) neurons:

Carries impulses from sensory receptos

vision, hearing, equlibrium, taste and smell, cutanieous (skin), pain, proprioceptors (muscle)

Motor (efferent) neurons:

Carry impulses from the CNS

Interneurons/ Associan neuron

Found in neural pathways of CNS

Connect sensory and motor neurons

Reflex vs. Reflex arc

Reflex- rapid, involuntary, predicatble response to stimuli

Reflex arc- involves CNS and PNS

direct route from senesory neuron to an interneuron and an effector

Gray vs White matter

Gray- myalated, outer layer, composed of neuron cell bodies

White- fiber tracts inside te gray matter

Basal nuclei

internal islands of gray matter

Dorsal horn vs Ventral horn

Dorsal- Afferent, collection of cell bodies outside the CNS, dorsal root ganglia

Ventral- efferent

Layers of cerebrum

gray matter, white matter, basal nuclei

2 subdivisions of nervous system

Central Nervous System(CNS): Brain, spinal cord, dorsal body cavity; interpret incoming sensory information and tissue intructions based on past experience or current conditions

Peripheral Nervous System(PNS): nerves leading to and from the brain and spinal cord

Cerebrospinal Fluid

like blood plasma, made by choroid plexus, water cushion for brain, circulated in arachnoid space, ventricles and central canal of the spinal cord

Protection of CNS

Scalp, skin, skull, meninges, cerebrospinal fuid, blood brain barrier

Meninges

dura matter, double layer

periosteum- surface of skull

Meningeal- outer covering of skull

Folds inward in several areas

Glial cells

brain cancer

never lose baility to divide

not able to transfer impulses

types: neuroglia, microglia, ependymal, oligodendrocytes, astrocytes

PNS types: staellite, schwann cells

Astrocytes

abundant, star-shaped cells, half of neural tissue

Microglia

spider like phagocytes

Ependymal Cells

lines cavities and brain and spinal cord, beaitng cilia to circulate CS fluid

Oligoderdrocytes

myelinated fibers, produce myeline sheath, lacks neurilemma

Satellite cells

protects, cushions neuron cell bodies

Schwann cells

forms myelin sheath in PNS