Systems Reviews

The nervous system: Central Nervous System

• Brain and spinal cord.

Peripheral Nervous System

• Everything else.

Peripheral Nervous System

• Somatic system: voluntary movement.

• Autonomic system: vital functions/involuntary movements.

Sympathetic Nervous System

• Fight or flight.

• Activated by adrenaline and noradrenaline.

• Thoracic and lumbar spinal cord.

• Neurotransmitters: epinephrine and norepinephrine.

  • Dilates pupils.

  • Increases heart rate/bronchodilation.

  • Inhibits digestion.

  • Stimulates adrenal medulla to secrete epinephrine and norepinephrine.

  • Alpha receptors.

  • Beta receptors.

Parasympathetic Nervous System

• Rest and relax.

• Activated by acetylcholine.

Autonomic Receptors - Nicotinic

• Nicotinic-ionotropic receptors.

• Common to parasympathetic and sympathetic nervous system.

• Acetylcholine binds to receptors.

• Ion channels open.

Beta Receptors

• B1 and B2 in the cardiovascular system.

• B1: are in the SA node, AV node, and atrial/ventricular cardiomyocytes.

• B2: vascular smooth muscle/coronary circulation.

Alpha Receptors

• A1: vascular smooth muscle, vasoconstriction.

• A2: vascular smooth muscle, vasodilation.

Parasympathetic Receptors

• Heart: M2 receptors.

• Lungs: M3 receptors.

Vagus Nerve (Wandering)

• Important parasympathetic nerve.

• 10th of the twelve cranial nerves (Cranial Nerve X).

• Runs from the brain to the large intestine.

• Innervates the sinoatrial node/AV node and ventricular conduction system (Cleveland Clinic, 2024).

Pulmonary Anatomy and Physiology

PULMONARY SYSTEM

• Ventilation: The process of moving air in and out of the lungs.

• Pulmonary Ventilation: Breathing.

• Alveolar Ventilation: Gas exchange.

THE LUNGS

• Trachea

• Bronchi

• Lobes:

  • Right lung: 3 lobes

  • Left lung: 2 lobes

• Alveoli

LUNG TISSUE

• Epithelial: Lines the airways and alveoli.

• Connective Tissue: Provides support for the lungs and bronchi.

• Smooth Muscle: Found in the walls of the bronchi and bronchioles.

• Alveoli: Small sacs where gas exchange takes place.

ALVEOLI

• Thin-walled blood vessels deliver oxygen and carbon dioxide to the alveoli for exchange.

PULMONARY VASCULATURE

• Diagram showing the flow of blood between the heart and lungs.

• Includes pulmonary veins and pulmonary arteries.

NERVOUS SYSTEM CONTROL

• Autonomic Nervous System

• Receptors in bronchial smooth muscle.

• Parasympathetic signals: Slow down breathing and narrow bronchial tubes while widening vessels.

RECEPTORS

• Chemoreceptors:

  • Located in the medulla, carotid bodies, and aorta.

  • Detect gas concentrations in the blood.

• Mechanoreceptors:

  • Located in the lungs and airway smooth muscle.

• Beta 2 receptors