September 30, 2023

Structure and functions of parasympathetic nervous system.

Structure and functions of parasympathetic nervous system.

The parasympathetic nervous system (PNS) is one of the two main divisions of the autonomic nervous system (ANS), which is responsible for controlling the involuntary functions of the body. The PNS is involved in regulating the body’s “rest and digest” responses, which involve restful activities and decreased physiological arousal. The PNS has several distinct structural and functional features.

Structure: The PNS is composed of a network of nerves that originate in the brainstem and the sacral region of the spinal cord, known as the craniosacral region. The PNS nerves emerge from the brainstem and sacral region through the cranial nerves and sacral spinal nerves, respectively. The PNS nerves extend to various organs, muscles, and glands throughout the body.

Functions: The PNS has several important functions, which include:

  1. Regulation of cardiovascular system: The PNS plays a critical role in regulating heart rate, blood pressure, and blood vessel diameter, which are all important for maintaining adequate blood flow to the body’s organs and tissues. The PNS helps to slow down the heart rate and reduce blood pressure during restful activities.
  2. Regulation of respiratory system: The PNS can also affect the respiratory system by decreasing breathing rate and volume during restful activities.
  3. Regulation of gastrointestinal system: The PNS can increase blood flow to the digestive organs, promote digestive secretions, and increase intestinal motility. This helps to support the body’s digestion and absorption of nutrients during restful activities.
  4. Regulation of metabolic rate: The PNS can decrease metabolic rate by promoting energy storage and conservation. This can help to support restful activities and conserve energy.
  5. Regulation of thermoregulation: The PNS can also play a role in regulating body temperature by increasing blood flow to the skin to release heat, or reducing blood flow to conserve heat.

Overall, the parasympathetic nervous system is an important regulatory system that is involved in promoting restful activities and reducing physiological arousal. Dysfunctions of the PNS can lead to a range of neurological disorders, including autonomic dysfunctions, gastrointestinal disorders, and cardiovascular disorders.

First Year B Pharm Notes, Syllabus, Books, PDF Subjectwise/Topicwise

F Y B Pharm Sem-IF Y B Pharm Sem-II
BP101T Human Anatomy and Physiology I TheoryBP201T Human Anatomy and Physiology II – Theory
BP102T Pharmaceutical Analysis I TheoryBP202T Pharmaceutical Organic Chemistry I Theory
BP103T Pharmaceutics I TheoryBP203T Biochemistry – Theory
BP104T Pharmaceutical Inorganic Chemistry TheoryBP204T Pathophysiology – Theory
BP105T Communication skills TheoryBP205T Computer Applications in Pharmacy Theory
BP106RBT Remedial BiologyBP206T Environmental sciences – Theory
BP106RMT Remedial Mathematics TheoryBP207P Human Anatomy and Physiology II Practical
BP107P Human Anatomy and Physiology PracticalBP208P Pharmaceutical Organic Chemistry I Practical
BP108P Pharmaceutical Analysis I PracticalBP209P Biochemistry Practical
BP109P Pharmaceutics I PracticalBP210P Computer Applications in Pharmacy Practical
BP110P Pharmaceutical Inorganic Chemistry Practical
BP111P Communication skills Practical
BP112RBP Remedial Biology Practical

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