Autonomic Nervous System

Autonomic Nervous System

• Definition: The autonomic nervous system (ANS) is a branch of the nervous system that regulates involuntary actions, such as heart rate, blood pressure, digestion, and respiration.
• Divisions:
  • Sympathetic nervous system (SNS): "fight or flight" response, prepares body for action
  • Parasympathetic nervous system (PNS): "rest and digest" response, promotes relaxation and reduces energy expenditure
• Functions:
  • Regulates heart rate and blood pressure
  • Controls digestion and absorption of nutrients
  • Modulates respiration and pH balance
  • Influences body temperature and sweating

Neurotransmitters

• Definition: Chemical messengers that transmit signals between neurons
• Types:
  • Excitatory neurotransmitters: stimulate the next neuron, e.g. glutamate, aspartate
  • Inhibitory neurotransmitters: reduce the activity of the next neuron, e.g. GABA, glycine
  • Modulatory neurotransmitters: influence the strength of synaptic transmission, e.g. dopamine, serotonin
• Functions:
  • Regulate mood, motivation, and reward
  • Involved in muscle contraction and relaxation
  • Modulate pain perception
  • Play a role in appetite and sleep regulation

Immune Response

• Definition: The body's defense against pathogens, such as bacteria, viruses, and other foreign substances
• Types of immune responses:
  • Innate immunity: non-specific, immediate response to pathogens
  • Adaptive immunity: specific, acquired response to pathogens
• Phases of immune response:
  1. Recognition: identification of pathogens by immune cells
  2. Activation: activation of immune cells to respond to pathogens
  3. Elimination: removal of pathogens from the body
  4. Memory: retention of immune cells to recognize and respond to future infections

Hormone Regulation

• Definition: Hormones are chemical messengers produced by endocrine glands that regulate various physiological processes
• Types of hormones:
  • Steroid hormones: derived from cholesterol, e.g. testosterone, estrogen
  • Peptide hormones: composed of amino acids, e.g. insulin, growth hormone
  • Amino acid hormones: derived from amino acids, e.g. thyroid hormone
• Functions:
  • Regulate growth and development
  • Control metabolism and energy production
  • Influence reproductive processes
  • Modulate stress response and mood

Lymphatic System

• Definition: A network of vessels, organs, and tissues that defend the body against infection and disease
• Components:
  • Lymphatic vessels: transport lymph fluid throughout the body
  • Lymph nodes: filter lymph fluid and trap pathogens
  • Spleen: filters blood and removes old red blood cells
  • Thymus: produces immune cells called T-lymphocytes
• Functions:
  • Defends against infection and disease
  • Regulates fluid balance and blood pressure
  • Aids in the absorption of fats and fat-soluble vitamins
  • Plays a role in the immune response

Autonomic Nervous System

• Regulates involuntary actions, such as heart rate, blood pressure, digestion, and respiration
• Divided into Sympathetic Nervous System (SNS) and Parasympathetic Nervous System (PNS)
• SNS triggers "fight or flight" response, preparing the body for action
• PNS promotes relaxation and reduces energy expenditure with a "rest and digest" response
• Regulates heart rate and blood pressure, controls digestion and absorption of nutrients
• Modulates respiration and pH balance, influences body temperature and sweating

Neurotransmitters

• Chemical messengers transmitting signals between neurons
• Types include excitatory, inhibitory, and modulatory neurotransmitters
• Excitatory neurotransmitters (e.g. glutamate, aspartate) stimulate the next neuron
• Inhibitory neurotransmitters (e.g. GABA, glycine) reduce the activity of the next neuron
• Modulatory neurotransmitters (e.g. dopamine, serotonin) influence the strength of synaptic transmission
• Regulate mood, motivation, and reward, involved in muscle contraction and relaxation
• Modulate pain perception, play a role in appetite and sleep regulation

Immune Response

• The body's defense against pathogens, such as bacteria, viruses, and other foreign substances
• Types of immune responses include innate immunity and adaptive immunity
• Innate immunity is non-specific, immediate response to pathogens
• Adaptive immunity is specific, acquired response to pathogens
• Phases of immune response: recognition, activation, elimination, and memory

Hormone Regulation

• Hormones are chemical messengers produced by endocrine glands
• Regulate various physiological processes
• Types of hormones: steroid hormones, peptide hormones, amino acid hormones
• Steroid hormones (e.g. testosterone, estrogen) are derived from cholesterol
• Peptide hormones (e.g. insulin, growth hormone) are composed of amino acids
• Amino acid hormones (e.g. thyroid hormone) are derived from amino acids
• Regulate growth and development, control metabolism and energy production
• Influence reproductive processes, modulate stress response and mood

Lymphatic System

• A network of vessels, organs, and tissues that defend the body against infection and disease
• Components include lymphatic vessels, lymph nodes, spleen, and thymus
• Lymphatic vessels transport lymph fluid throughout the body
• Lymph nodes filter lymph fluid and trap pathogens
• Spleen filters blood and removes old red blood cells
• Thymus produces immune cells called T-lymphocytes
• Defends against infection and disease, regulates fluid balance and blood pressure
• Aids in the absorption of fats and fat-soluble vitamins, plays a role in the immune response