Summary body and behaviour
Problem 1 your point of view
General layout of the nervous system
Divisions of the nervous system
nervous system
central nervous peripheral
system CNS nervous system
PNS
autonomic
somatic nervous
nervous system
system SNS
spinal cord brain ANS
afferent nerves; efferent nerves; afferent nerves; efferent nerves;
receive act receive act
sympathetic parasympathetic
nervous system nervous system
• Somatic nervous system communicates w/ external environment;
o Afferent nerves carry sensory signals
o Efferent nerves carry motor signals
o → from sensory organs to CNS
• Autonomic nervous system regulates body’s internal environment;
o Afferent nerves carry sensory signals
o Efferent nerves carry motor signals;
▪ Sympathetic nerves= autonomic motor nerves projecting from CNS
▪ Parasympathetic nerves= autonomic motor nerves projecting from
brain
o →from internal organs to CNS
• 12 pairs of cranial nerves
o Project from brain
o Some purely sensory→ olfactory and optic
o Most both sensory and motor
Meninges
brain and spine (CNS) is the most protected organ in the body→ 3 protective membranes=
meninges
, 1. Dura mater= outer meninx
2. Arachnoid membrane→ inside dura mater
a. Beneath arachnoid membrane is subarachnoid space
3. Pia mater= innermost meninx
Ventricles and cerebrospinal fluid
Also protecting CNS= cerebrospinal fluid→ fills;
• Subarachnoid space
• Central canal; small central channel running length of spinal cord
• Cerebral ventricles; 4 large internal chambers of brain
o 2 lateral ventricles
o Third ventricle
o Fourth ventricle
• →interconnected by openings, form single reservoir
• Supports and cushions brain
• Produced by choroid plexuses
• Excess cerebrospinal fluid absorbed from subarachnoid space into blood filled
spaces= dural sinuses → run through dura mater and drain into jugular veins of neck
• Build up of fluid→ walls ventricles and thus brain expand= waterhead; hydrocephalus
Blood-brain barrier
= mechanism impeding passage of many toxic substances from blood into brain→
consequence of special structure of cerebral blood vessels
• Cells of blood walls tightly packed→ barrier to passage many molecules;
o Proteins
o Large molecules
, • Degree to which drugs can influence activity depends on ease w/ which they
penetrate blood-brain barrier
• Some large molecules (Glucose) critical for normal brain function→ actively
transported through central blood vessel walls
• Many CNS disorders associated w/ impairment blood-brain barrier
Cells of the nervous system
1. Neurons= cells specialized for the reception, conduction and transmission of
electrochemical signals
a. External anatomy of neurons
b.
c. Internal anatomy of neurons
, d.
e. Neuron cell membrane= composed of lipid bilayer;
i. Protein molecules→ basis functional properties ;
1. Channel proteins
2. Signal proteins
f. Classes of neurons
Problem 1 your point of view
General layout of the nervous system
Divisions of the nervous system
nervous system
central nervous peripheral
system CNS nervous system
PNS
autonomic
somatic nervous
nervous system
system SNS
spinal cord brain ANS
afferent nerves; efferent nerves; afferent nerves; efferent nerves;
receive act receive act
sympathetic parasympathetic
nervous system nervous system
• Somatic nervous system communicates w/ external environment;
o Afferent nerves carry sensory signals
o Efferent nerves carry motor signals
o → from sensory organs to CNS
• Autonomic nervous system regulates body’s internal environment;
o Afferent nerves carry sensory signals
o Efferent nerves carry motor signals;
▪ Sympathetic nerves= autonomic motor nerves projecting from CNS
▪ Parasympathetic nerves= autonomic motor nerves projecting from
brain
o →from internal organs to CNS
• 12 pairs of cranial nerves
o Project from brain
o Some purely sensory→ olfactory and optic
o Most both sensory and motor
Meninges
brain and spine (CNS) is the most protected organ in the body→ 3 protective membranes=
meninges
, 1. Dura mater= outer meninx
2. Arachnoid membrane→ inside dura mater
a. Beneath arachnoid membrane is subarachnoid space
3. Pia mater= innermost meninx
Ventricles and cerebrospinal fluid
Also protecting CNS= cerebrospinal fluid→ fills;
• Subarachnoid space
• Central canal; small central channel running length of spinal cord
• Cerebral ventricles; 4 large internal chambers of brain
o 2 lateral ventricles
o Third ventricle
o Fourth ventricle
• →interconnected by openings, form single reservoir
• Supports and cushions brain
• Produced by choroid plexuses
• Excess cerebrospinal fluid absorbed from subarachnoid space into blood filled
spaces= dural sinuses → run through dura mater and drain into jugular veins of neck
• Build up of fluid→ walls ventricles and thus brain expand= waterhead; hydrocephalus
Blood-brain barrier
= mechanism impeding passage of many toxic substances from blood into brain→
consequence of special structure of cerebral blood vessels
• Cells of blood walls tightly packed→ barrier to passage many molecules;
o Proteins
o Large molecules
, • Degree to which drugs can influence activity depends on ease w/ which they
penetrate blood-brain barrier
• Some large molecules (Glucose) critical for normal brain function→ actively
transported through central blood vessel walls
• Many CNS disorders associated w/ impairment blood-brain barrier
Cells of the nervous system
1. Neurons= cells specialized for the reception, conduction and transmission of
electrochemical signals
a. External anatomy of neurons
b.
c. Internal anatomy of neurons
, d.
e. Neuron cell membrane= composed of lipid bilayer;
i. Protein molecules→ basis functional properties ;
1. Channel proteins
2. Signal proteins
f. Classes of neurons
