Anatomy Sem 2 Lecture 1

Front 1

Nervous system(Systema Nervosum)

Back 1

Controls and coordinates all essential functions ofthe human body

Monitors and responds to internal and external changes.

All parts of nervous system are made of nervous tissue

Front 2

Nerve tissue

Back 2

Composed of:

Neurons - transmit impulses

Neuroglia - assist for transmitting the impulses and providingnutrients to the neurons

Front 3

Neurons

Back 3

Neuron consists of cell body, dendrites and axon

Front 4

Dendrites

Axon

Back 4

Dendrites areshort extensions spreading out from the cell body; they receive stimuli and carry impulsesfrom enviroment or other neurons toward the cell body

Axon is a long fibre that carriesimpulses from the cell body; each neuron has only one axon

Front 5

Neurons functionally are of three types:

Afferent

Efferent

Interneurons

Back 5

Afferent (sensory) neurons – convey the information from tissue and organ to the brain and spinal cord; they start with receptors.

Efferent (motor) neurons – carry impulses from the brain and spinal cord to the effectors(muscles).

Interneurons - connect afferent and efferent neurons and carry impulses between them.

Front 6

Central nervous system

Back 6

Consist of:

Medulla spinalis

Encephalon

Front 7

Medulla spinalis

Back 7

Thespinal cord, lodged in the vertebral canal

Front 8

Encephalon

Back 8

The brain, contained within theskull

Front 9

Peripheral nervous system

Consists of?

Divided into:

Function:

Back 9

Consists of the neurons not included in the brain and spinal cord. Peripheral neurons collect information from the body and transmit it towards the CNS

Divided into:

nn spinalis (31 Pairs)

nn cranialis (12 pairs)

pars autonomica systematis nervosi peripherici

Function:

Coordinating body movements

Receiving external stimuli

Regulate activities under conscious control.

Supply the skeletal and muscular systems

Front 10

Autonomic part of nervous system

Function?

Has 2 parts?

Back 10

Function:

Supplies the internal organs,

Supplies blood and lymph vessels,

Supplies smooth muscular tissue of the skin

Supplies the glands,

Supplies the heart

Has 2 parts:

sympathetic part – pars sympathica;

parasympathetic part – pars parasympathica

Front 11

sympathetic part – pars sympathica

Function?

Back 11

Helps body in stress and emergency situations:

acceleration ofheart beating

respiratory frequence

narrows thediameter of the blood vessels

elevates the blood pressure,

dilates the pupil

increases the perspiration

Front 12

parasympathetic part – pars parasympathica

Function?

Back 12

It serves to build up resources:

determines slowing of the heart beating

lowering of respiratory frequence,

dilates the diameter of the blood vessels

Front 13

Medulla spinalis

Length:

Weight:

Diameter

Location

-Cranially

-Caudally

Back 13

Development:

Foetal life develops from the neural tube.

Length:

40-45 cm

Weight:

34-38g

Diameter

about 1 cm

Morphology

Cylindrical

Location

Cranially:

In the vertebral canal and at the level of foramen magnum it continues to the brain

Caudally:

It terminates by conus medullaris at the level of the 1st or the 2nd lumbar vertebra.

Front 14

Conus medullaris continue as?

Back 14

Filum terminale

Front 15

Filum terminale

Location

Length

Diameter

Back 15

Rudimental lower part of the neural tube!

Starts:

L1-L2

Finish:

Periosteum ofos coccygis at the level of the 2nd coccygeal vertebra.

The length:

20 cm

diameter:

1 mm.

Front 16

External surface of the spinal cord

Two unpaired grooves?

Two paired grooves?

Back 16

Fissura mediana anterior

Sulcus medianus posterior

Sulcus anterolateralis dexter et sinister

Sulcus posterolateralis dexter et sinister

Front 17

Segments of medulla spinalis

Spinal cord is shorter than the vertebral canal?

Location of segments?

Thoracic

Lumbar

Sacral

Back 17

Pars Cervicalis - Segmenta cervicalia 8 pairs

Pars Thoracica - Segmenta Thoracica 12 pairs

Pars Lumbalis - Segmenta Lumbalia 5 pairs

Pars Sacralis - Segmenta Sacralia 5 pairs

Pars Coccygea - Segmenta Coccygeum 1 pair

Spinal cord is shorter than the vertebral canal:

Upper cervical segments correspond to upper cervical vertebrae but lower and cervical and upper thoracic segments are one vertebrae above the corresponding level.

The 10th, the 11th and the 12th thoracicsegments are localized at the level of the 8th and the 9th thoracic vertebra.

The lumbarsegments lie at the level of the 10th and the 11th thoracic vertebra.

All sacral segments andcoccygeal segment are localized at the level of the 12th thoracic and the 1st or the 2nd lumbarvertebrae.

Front 18

Medulla spinalis has two swellings or enlargements?

Back 18

1. Intumescentia cervicalis - From 3 rd cervical to the 2 nd thoracic segments, more developed of 5th and 6th segment

2. Intumescentia lumbosacralis – from the 12th thoracic segment to conus medullaris.

!!Supply the upper and lower limbs with nerves!!

Front 19

Structure of Nervi Spinales?

Five groups

Each spinal nerve has 2 roots

Back 19

nn. cervicales (8) – the cervical nerves,

nn. thoracici (12) – the thoracic nerves,

nn. lumbales (5) – the lumbar nerves,

nn. sacrales (5) – the sacral nerves,

n. coccygeus (1) – the coccygeal nerve.

Radix sensoria

Radix motoria

Front 20

Radix sensoria?

Pseudounipolar sensory cells?

2 processes?

Back 20

Spinal ganglion:

Pseudounipolar sensory cells (1 Axon and 2 branches):

1) Peripheral processes (Dendrites) - from the cell body to the periphery

2) Central processes (Axons) - from the cell body to spinal cord

Front 21

Radix Motoria

2 Parts?

-Location?

Back 21

Comes out from medulla spinalis on sulcus anterolateralis.

Via the motorroot of the spinal cord leaves also:

1) Sympathetic (from the 8th cervical to the 2nd lumbarsegments) fibres.

2) Parasympathetic (from the 2nd to the 4th sacral segments) fibres.

Front 22

N.Spinalis

Contains?

The motor and sensory roots of the lumbar, sacral and coccygeal segments descends along?

4 Branches?

Back 22

Both roots form the spinal nerve.

Each spinal nerve is mixed nerve, which contains sensory, motor and sympathetic or parasympathetic fibres.

Each spinal nerve leaves the vertebral canal through foramen intervertebrale.

The motor and sensory roots of the lumbar, sacral and coccygeal segments descends along filum terminale forming a common band – cauda equina.

4 Branches:

Ramus ventralis s anterior

Ramus dorsalis s posterior

Ramus communicans albus

Ramus meningeus

Front 23

Ramus ventralis s anterior

Supply?

Plexus?

Ventral branches of thoracic region?

Back 23

Supplies skin and muscles of the limbs

Supplies the lateral and anterior parts of the trunk.

The ventral branches of the spinal nerves form the plexus:

– plexus cervicalis,

– plexus brachialis,

– plexus lumbalis,

– plexus sacralis.

In thoracic region the ventral branches of the spinal nerves do not form plexus, but run asseparate nerves – nn. intercostales;

Front 24

Ramus dorsalis s posterior

Supply?

Back 24

supply the deep muscles of the back, partly the skin of :

occipital region

posterior part of the neck

of the back

Front 25

Ramus communicans albus

Contains?

Back 25

Contains the sympathetic fibres

Front 26

Ramus meningeus

Supplies?

Back 26

supplies the meninges of the spinal cord.

Front 27

Reflex arc

2 arcs?

Back 27

Afferent fibres receive a irritation and transmits the signal to 1st neurons this can form two different reflex arcs:

1) Monosynaptic reflex arc;

Transmits impulses directly to the efferent or motor neuron of anterior horn (the 2nd neuron)

2) Multisynaptic reflex arc:

transmits signal first to the intermediate neuron (the 2nd neuron) and then to the efferent neuron (the 3rd neuron) –

Efferent fibres then transmits signal to the muscle (effector)

Front 28

Internal features of medulla spinalis

Canalis centralis?

Medulla spinalis consist of?

Three horns of the gray matter?

Funiculus of white matter?

Back 28

In the central part of medulla spinalis runs the canal

– canalis centralis

the remnant of the cavity of the neural tube. Its diameter is about 1 mm. After the age of 40 it may be overgrown.

Canalis centralis contains liquid – liquor cerebrospinalis.

Medulla spinalis consist of:

1) substantia grisea – formed by the bodies of neurons.

is H–shaped on horizontal section.

Three horns of the gray matter:

– cornu anterius

– cornu laterale,

– cornu posterius

2) substantia alba –

formed by:

axons and dendrites

Funiculus of white matter:

– funiculus anterior –

– funiculus lateralis –

– funiculus posterior –

Front 29

Substantia Grisea

-Cornu anterius?

-Cornu laterale?

-Cornu posterius?

Back 29

The horns of the grey matter through the entire lenght of the spinal cord form the columns.

-Cornu anterius through the entire lenght of medulla spinalis

-Cornu laterale is present only from the 8th cervical to the 2nd lumbar segments and from the 2nd tothe 4th sacral segments of the spinal cord;

-Cornu posterius is present throughout the entire lenght of the spinal cord

The grey matter around canalis centralis is substantia gelatinosa centralis.

Front 30

Columna anterior (cornu anterius)

Contains?

Back 30

Contains several motor nuclei

Front 31

Columna posterior (cornu posterius)

Function?

Back 31

Sensory pathways of pain, temperature and tactile sense.

Front 32

Columna intermedia

Nucleus(4)?

Back 32

Nucleus thoracicus posterior

Nucleus intermediomedialis

Nucleus intermediolateralis

Nuclei parasympathici sacrales

Front 33

Nucleus thoracicus posterior

Function?

Back 33

Unconscious proprioception or the deep sensation;

Front 34

Nucleus intermediomedialis

Function?

Back 34

Unconscious proprioception or deep sensation pathway;

Front 35

Nucleus intermediolateralis

Contains?

From?

Back 35

Sympathetic cells in the lateral horn

From the 8th cervical to the 2nd lumbar segments

Front 36

Nuclei parasympathici sacrales

Contains?

From?

Back 36

Parasympathetic cells in the lateral horn

From the 2nd to the 4th sacral segments.

Front 37

Fasciculi proprii?

Back 37

Ascending and descending association fibers of the spinal cord that lie at the gray matter–white matter border!

Front 38

Formatio reticularis spinalis.

Contains?

Function?

Back 38

Consists:

Scattered neurons and the network of theircommunicating processes.

Function:

sensory irritability,

regulates respiration,

heartbeating

blood pressure,

state of consciousness.

Front 39

Substantia alba

Back 39

The nerve fibres of the white matter are arranged into tracts, there are two groups of tracts:

1 Tractus ascendentes s. afferentes

2 Tractus descendentes s. efferentes

Front 40

Tractus ascendentes s. afferentes

Two groups:

Conscious(4)?

Unconscious(2)?

Back 40

Two groups

a) conscious – they conduct impulses to the cortex:

tractus spinothalamicus anterior

tractus spinothalamicus lateralis

fasciculus gracilis

fasciculus cuneatus

b) unconscious – they conduct impulses to the cerebellum:

tractus spinocerebellaris anterior

tractus spinocerebellaris posterior

Front 41

Tractus descendentes s. efferentes

Pyramidal tracts(2)?

Extrapyramidal tracts(6)?

Back 41

Descending or motor tracts conduct motor impulses from the brain to the spinal cord and are subdivided into two groups:

a) pyramidal tracts for voluntary movements: tractus corticospinalis anterior

tractus corticospinalis lateralis

b) extrapyramidal tracts for involuntary movements:

tractus rubrospinalis

tractus tectospinalis

tractus vestibulospinalis

tracus olivospinalis

fasciculus longitudinalis medialis

tractus reticulospinalis

Front 42

Funiculus Posterior

Fasciculus gracilis

Fasciculus cuneatus

Fasciculus gracilis et cuneatus

Function:

Epicritic sensibility?

Back 42

3 parts:

Fasciculus proprius posterior

Ascending tracts(2):

1) fasciculus gracilis – -->lower part of the trunk and the lower limbs

Present in all segments of the spinal cord;

2) fasciculus cuneatus ->upper part of the trunk and the upper limbs

only above the 5th thoracic segment.

Fasciculus gracilis et cuneatus

1st neurons:

spinalganglion.-->

2nd neurons:

medulla oblongata

Function:

impulses from

proprioreceptors

exteroreceptors

Epicritic sensibility, what gives informationabout the position of the body parts and their movements.

Front 43

Funiculus lateralis

Fasciculus proprius lateralis

Tractus ascendentes?(3)

Tractus descendentes?(2)

Back 43

3 Parts:

Fasciculus proprius lateralis

Tractus ascendentes

Tractus descendentes

Tractus ascendentes:

1) Tractus spinocerebellaris posterior –

nucleus thoracicus posterior -> cerebellum;

2) tractus spinocerebellaris anterior –

nucleus intermedio medialis, -> cerebellum;

Tractus spinocerebellaris anterior et posterior:

1 neurons: Spinal ganglion to:

2nd neurons – nucleus thoracicus posterior or nucleus intermedio medialis;

Formation of unconscious proprioceptive pathway:

3) tractus spinothalamicus lateralis –

nucleus proprius ->thalamus.

It takes part information of pain and temperature pathway:

1st neurons spinal ganglion; -->

2nd neuron –nucleus proprius.

Tractus Descendentes:

1) Tractus corticospinalis lateralis

cortex--> nuclei motorii cornu anterioris;

voluntary control of skeletal muscles for the trunk and limbs.

2) Tractus rubrospinalis

Mesencephalon

controls habitual movements,

coordination of movements

Front 44

Funiculus Anterior

Fasciculus proprius anterior

Ascending tracts? (1)

Descending tracts? (6)

Back 44

3 parts:

Fasciculus proprius anterior

Ascending tracts (1)

Descending tracts (6)

Tractus ascendens:

1. tractus spinothalamicus anterior

nucleus proprius -> thalamus.

It takes part information of touch pathway:

Tractus descendentes:

1) tractus corticospinalis anterior:

Brain -> nuclei motorii cornu anterioris;

regulates voluntary control of skeletal muscles for the trunk and limbs.;

2) tractus tectospinalis mesencephalon;

it is part of the extrapyramidalsystem and is responsible for coordinating the head and eye movements;

3) fasciculus longitudinalis medialis –

Motor nuclei III, IV, VI and XI cranial nerves -> nuclei motorii of spinal cord.

Only present in cervical segments

coordinates involuntary movements of the head, neck and eye ;

4) tractus vestibulospinalismedulla oblongata;

it is responsible forinvoluntary movements concerned with the balance and posture; it is part of balance pathway;

5) tractus olivospinalis – medulla oblongata; it is responsible for involuntary movements concerned with the balance and posture; it is part of balance pathway;

6) tractus reticulospinalis –

formatio reticularis spinalis

and has an influence to the motor system and on the state of consciousness.

Front 45

MENINGES OF SPINAL CORD

Spatium epidurale -

1) spinal dura mater

Spatium subdurale

2) arachnoid mater

spatium subarachnoideum

3) spinal pia mater

Back 45

The spinal cord is surrounded by three meninges:

Spatium epidurale - Filled with fatty tissue, lymphatic vessels and venous plexus

1) spinal dura mater – dura mater spinalis; spinal

Spatium subdurale - True cavity only under pathological conditions, haemorrhage!

2) arachnoid mater – arachnoidea mater spinalis

Fuses with brain and cranially and caudally with terminal filum

Spatium subarachnoidea - Filled with liquor cerebrospinalis.

3) spinal pia mater – pia mater spinalis.

Vascular, lies directly to spinal cord!

Upward it continues into similar covering for the brain, downward it covers the terminal filum.

Front 46

Lumbar puncture

Where?

Why?

Back 46

A lumbar puncture between 3rd and the 4th lumbar vertebras.

Cause the medulla spinalis ends at 1st to 2nd Lumbar vertebrae

The lumbar puncture is carried out to obtain a sample of cerebrospinal fluid for examination.

Also for injecting antibiotics