Human Development – Lecture 24 – PNS
CNS and PNS;
Somatic; 1 step to skeletal muscle
Autonomic; 2 steps to smooth muscle,
cardiac muscle and gland cells
• Sympathetic; preganglionic =
short, postganglionic = long
T1-L3
• Parasympathic; preganglionic =
long, postganglionic = short
Medulla, pons, mesencephalon
and S2-S4 (craniosacral aystem)
CNS;
• Brain
• Spinal cord
PNS;
• Cranial nerves; 12 sets of 2 branches originate from
the brain.
4 parasympathetic.
• Spinal nerves; 31 pairs. It is a mixed nerve from
branches of sensory (somatic + autonomic) + motor
(somatic + autonomic) and carry signals from CNS to periphery. The spinal
nerve starts when dorsal and ventral tracts merge.
Components in spinal nerve; Somatic sensory neuron, visceral
(autonomic) sensory neuron, autonomic motor neuron and
somatic motor neuron.
Radix (gescheiden) → spinal nerve (gemengd) → ramus
(gemengd)
8 Cervicale
12 Thoracic
5 Lumbar
5 Sacral
1 coccygeal (staartbeen)
• Autonomic nerves
Sympathetic; in spinal nerves
Parasympathetic; partially in cranial nerves
• Enteric nervous system
ENS communicate with CNS via the vagus nerve (n. X) and they sympathetic
nervous system
It can function entirely independently as if it had its own “brain”.
It contains motor, sensory and interneurons.
It used more than 30 neurotransmitters
CNS and PNS;
Somatic; 1 step to skeletal muscle
Autonomic; 2 steps to smooth muscle,
cardiac muscle and gland cells
• Sympathetic; preganglionic =
short, postganglionic = long
T1-L3
• Parasympathic; preganglionic =
long, postganglionic = short
Medulla, pons, mesencephalon
and S2-S4 (craniosacral aystem)
CNS;
• Brain
• Spinal cord
PNS;
• Cranial nerves; 12 sets of 2 branches originate from
the brain.
4 parasympathetic.
• Spinal nerves; 31 pairs. It is a mixed nerve from
branches of sensory (somatic + autonomic) + motor
(somatic + autonomic) and carry signals from CNS to periphery. The spinal
nerve starts when dorsal and ventral tracts merge.
Components in spinal nerve; Somatic sensory neuron, visceral
(autonomic) sensory neuron, autonomic motor neuron and
somatic motor neuron.
Radix (gescheiden) → spinal nerve (gemengd) → ramus
(gemengd)
8 Cervicale
12 Thoracic
5 Lumbar
5 Sacral
1 coccygeal (staartbeen)
• Autonomic nerves
Sympathetic; in spinal nerves
Parasympathetic; partially in cranial nerves
• Enteric nervous system
ENS communicate with CNS via the vagus nerve (n. X) and they sympathetic
nervous system
It can function entirely independently as if it had its own “brain”.
It contains motor, sensory and interneurons.
It used more than 30 neurotransmitters
