HSS 305 Human Anatomy Exam 2 Review

Central Nervous System (CNS)

brain and spinal cord

Peripheral nervous system (PNS)

the sensory and motor neurons that connect the central nervous system (CNS) to the rest of the body.

Neurons

Cells transmitting nerve impulses.

Cell body

contains nucleus cytoplasm and organelles

nucli vs ganglia

clusters of cell bodies in CNS are called nuclei vs clusters of cell bodies in PNS are called ganglia

Dendrites

Receive signals from other neurons.

Axon

Transmits impulses away from the cell body.

ion channels in plasma membrane

converts chemical potential to electrical potential

structural categories of neurons

anaxonic, bipolar, pseudounipolar, multipolar

synapse

Gap between neurons

presynaptic terminals

transmit elements of the neuron

postsynaptic membrane

the cell membrane opposite the terminal button in a synapse; the membrane of the cell that receives the message

synaptic cleft

gap between adjacent neurons

Neurotransmitters

chemical messengers

Myelin Sheath

Insulating layer around axons. white matter

oligodendrocytes vs schwann cells

CNS = oligodendrocytes

PNS = Schwann cells

Nodes of Ranvier

Gaps in myelin sheath for faster conduction.

Saltatory Conduction

Impulse jumps between nodes, speeding transmission.

afferent neurons

carries impulses from sensory receptors to the CNS

efferent neurons

carry impulses from CNS to muscles or glands

integrative neurons

decide impulse sent to motor neurons

Gray Matter

Contains neuron cell bodies and synapses, basal nuclei, cerebral cortex

White Matter

Contains myelinated axons for signal transmission, corpus collasum, anterior and posterior commisures and internal capsule

glial cells

cells in the nervous system that support, nourish, and protect neurons

multiple sclerosis

an autoimmune disease that is the result of the immune systems attack on myelin proteins & affects mostly young adults

myasthenia gravis

autoimmune neuromuscular disorder characterized by weakness of voluntary muscles

Tetrodotoxin poisoning

puffer fish disease

Cerebrum

Largest brain region, responsible for higher functions.

frontal lobe

A region of the cerebral cortex that has specialized areas for movement, abstract thinking, planning, memory, and judgement

parietal lobe

A region of the cerebral cortex whose functions include processing information about touch.

occipital lobe

A region of the cerebral cortex that processes visual information

temporal lobe

A region of the cerebral cortex responsible for hearing and language.

central sulcus

separates frontal and parietal lobes

lateral sulcus

separates the parietal and temporal lobes

parieto-occipital sulcus

separates parietal and occipital lobes

basal nuclei function

Controls muscle activity and posture; largely inhibits unintentional movement when at rest

parkinsons disease

A disorder of the central nervous system that affects movement, often including tremors.

huntingtons disease

Genetic disorder that causes progressive deterioration of brain cells. caused by a dominant allele. symptoms do not appear until about the age of 30.

cerebral cortex: sensory

primary sensory cortex, primary visual cortex,

olfactory cortex, gustatory cortex, auditory cortex

cerebral cortex: motor

primary motor cortex, broca's area

cerebral cortex: integrative

somatosensory association area, premotor area,

visual association area, Wernicke's area

Limbic System

Involved in emotions and memory.

Thalamus

Relay station for sensory information.

hypothalamus

homeostasis, thirst and hunger centers, endocrine

function

Epithalamus (pineal gland)

produces melatonin

midbrain

auditory and visual reflexes

pons

respiration (cyclical at rest)

medulla

- primary reflexes (hiccupping, coughing, vomiting,

sneezing, etc.) and change in HR and respiratory rate

cerebellum

Cerebellum

Coordinates voluntary movements and balance.

Meninges

Protective membranes surrounding the brain.

CSF

Cerebrospinal fluid cushioning the brain. produced by choroid plexus (ependymal cells lining

blood capillaries) (within ventricles)

lateral ventricle

produces and contains cerebrospinal fluid

third ventricle

The midline ventricle that conducts cerebrospinal fluid from the lateral ventricles to the fourth ventricle.

fourth ventricle

the passageway within the pons that receives cerebrospinal fluid from the third ventricle and releases it to surround the brain and spinal cord

Prosencephalon

The embryonic portion of the brain that becomes the forebrain.

mesencephalon

the midbrain; a region of the brain that surrounds the cerebral aqueduct; includes the tectum and the tegmentum

rhombencephalon

the embryonic portion of the brain that becomes the hindbrain

Hydrocepalus

accumulation of fluid in the spaces of the brain

Traumatic brain injury

mild or severe trauma that can result from a violent impact to the head

concussion

a bruise like injury of the brain

Chronic traumatic encephalopathy

multiple head traumas- cognitive decline/memory deficits, + parkensins symptoms

stroke

Damage to the brain from interruption of its blood supply.

Somatic nervous system

Division of the PNS that controls the body's skeletal muscles.

Autonomic nervous system

The part of the PNS that controls the glands and the muscles of the internal organs.

Sympathetic nervous system

fight or flight

parasympathetic system

rest and digest

Spinal Cord

Transmits signals between brain and body.

ventral horn

gray mater, somatic motor

lateral horn

gray mater, autonomic motor

dorsal horn

gray mater, axons sensory and cell bodies interneurons

spinothalamic tract

sensory, nerve pathway from the spine to the thalamus along which pain impulses are carried to the brain

corticospinal tract

motor pathway that controls movements of fingers, hands, arms, trunk, legs, feet

cervical plexus

C1-C4, phrenic nerve, transverse cervical nerve, supraclavicular

nerves

Brachial plexus

C5-T1, musculocutaneous nerve, median nerve, ulnar nerve, axillary

nerve, radial nerve, medial brachial and antebrachial

cutaneous nerves

intercostal nerve

thoracic ventral rami, muscles and skin of lateral and anterior trunk

lumbar plexus

L1 - L4, femoral nerve, obturator nerve, lateral femoral cutaneous

nerve

sacral plexus

L4 - S4, posterior femoral cutaneous nerve, superior and inferior

gluteal nerves, sciatic nerve: tibial nerve + common fibular

nerve (superficial fibular nerve + deep fibular nerve)

epineurium

covers whole nerve

perineurium

covers fascicles

endoneurium

covers individual axons

Primary reflexes (cranial intergration)

present at birth, integration happens in brain

learned reflexes (spinal integration)

integration take place in spine, learned the reflex later on

Reflex Arc

Pathway for reflex actions, sensory receptor, sensory neuron, integrating center, motor neuron,

effector