Comprehensive Medical Physiology Review

Flashcards covering key vocabulary and concepts from a lecture on lung volumes, capacities, airway resistance, renal physiology, autonomic control of the cardiovascular system, reflexes, sensory system, pain sensation, body's response to surgery, inflammation and tissue healing, and acid-base balance.

Spirometry

Pulmonary ventilation (volume of air moved in & out of lungs) is recorded by this method.

Tidal Volume (TV)

Volume of air inhaled or exhaled per breath.

Inspiratory Reserve Volume (IRV)

Volume of air forcibly inhaled above TV.

Expiratory Reserve Volume (ERV)

Volume of air forcibly exhaled after TV.

Residual Volume (RV)

Volume of air remaining in lungs after maximal expiration.

Inspiratory Capacity (IC)

Maximum volume of air that can be inspired after normal expiration (TV + IRV).

Functional Residual Capacity (FRC)

Volume of air remaining in lungs after TV is expired (ERV + RV).

Vital Capacity (VC)

Volume of air that can be expired after a maximal inspiration (TV + IRV + ERV).

Total Lung Capacity (TLC)

Volume of air in the lungs after maximal inspiration (sum of all four volumes).

Minute Respiratory Volume

Volume of air inspired per minute (tidal volume x breaths/min).

Partial Pressure of Gases

Amount of pressure exerted by each type of gas in a mixture of gases.

Bronchoconstriction

Contraction of bronchiolar smooth muscles due to parasympathetic stimulation.

Bronchodilation

Relaxation of bronchiolar smooth muscles due to sympathetic stimulation.

External Respiration

Exchange of air between the atmosphere and the lungs.

Internal Respiration

Utilization of O2 and production of CO2 by cells.

Conducting Zone

Extends from the trachea to the terminal bronchioles; conducts air towards the alveoli.

Respiratory Zone

Extends from the respiratory bronchioles to the alveoli; permits gas exchange with blood.

Alveolocapillary Membrane

The membrane composed of fluid lining alveoli and layers of epithelial and endothelial cells for gas diffusion.

Pulmonary Ventilation

Inflow and outflow of air between the atmosphere and lungs through inspiration and expiration.

Intra-alveolar Pressure (PA)

Pressure inside the alveoli.

Intrapleural Pressure (PPL)

Pressure inside the narrow space between the two layers of pleura.

Outer Cortex

Outer portion of the kidney.

Inner Medulla

Inner portion of the kidney.

Nephron

Functional unit of the kidney responsible for forming urine.

Renal Corpuscle

Part of the nephron where blood filtration occurs.

Renal Corpuscle Components

Glomerulus and Bowman's capsule.

Renal Tubule

Part of the nephron that modifies the composition of tubular fluid.

Renal Tubule Segments

Proximal convoluted tubule (PCT), Loop of Henle (LH), and Distal convoluted tubule (DCT).

Tubular Reabsorption

Movement of substances out of the tubular fluid to the renal interstitium and then to blood.

Tubular Secretion

Movement of substances from peritubular capillary blood to renal interstitium and then to tubular lumen.

Glomerular Filtration Rate (GFR)

The volume of fluid filtered by glomeruli of both kidneys per minute.

Forces Affecting GFR

Net filtration pressure and glomerular capillary filtration coefficient (Kf).

Vasomotor Centre (VMC)

Origin of sympathetic adrenergic control in the cardiovascular system.

Cardioinhibitory Centre (CIC)

Origin of parasympathetic cholinergic control in the cardiovascular system.

Bradycardia

Decrease in heart rate.

Tachycardia

Increase in heart rate.

Muscle Stretch Reflex

Muscle contraction in response to stretch.

Receptor for Stretch Reflex

Muscle spindle.

Anterior Horn Cells (AHCs)

Contains alpha and gamma motor neurons.

Renshaw Cell

Inhibitory interneuron in the anterior horn.

Inverse Stretch Reflex

Reflex skeletal muscle relaxation in response to increased muscle tension.

Receptor for Inverse Stretch Reflex

Golgi Tendon Organ (GTO).

Withdrawal Reflex

Reflex flexion and withdrawal of a limb from a painful stimulus.

Crossed Extensor Reflex

Contraction and extension of the limb in response to painful stimulus to the opposite limb.

Sensory Receptors

Specialized structures at the peripheral ends of sensory neurons.

Sensory Transduction

Transforming stimuli into action potentials.

Muller’s Law

The receptors respond to a particular form of energy (adequate stimulus).

Weber Fechner Law

Frequency of discharge from receptors is directly proportional to the logarithm of intensity of applied stimuli.

Adaptation

Decline in the frequency of discharge of action potential from receptors that occurs on maintained stimulation.

Coding of Sensory Information

Ability of nervous tissue to discriminate the modality, locality, and intensity of various sensations.

Labeled Line Principle

The stimulation of a certain sensory pathway produces sensation for which receptors are specialized.

Sensory Unit

A single afferent neuron with all its receptor endings.

Receptive Field

Area of the body that, when stimulated, leads to activity in a particular afferent neuron.

Sensation

Information about the environment obtained by sensory receptors.

Perception

Process by which the brain selects, organizes, and interprets sensations.

Dermatome

Area of skin that sends information to the brain via a single spinal nerve.

Pain

Unpleasant sensation caused by noxious stimulation.

Pain receptors

Free Nerve Endings

Three Types of Pain

Types of Stimuli that Excite Pain Receptors— Mechanical, Thermal, and Chemical.

Chemical Pain Stimuli

Extracts from damaged tissue causes intense pain

Pain Sensation

Pain that Occurs whenever any tissues are being damaged, and it causes the individual to react to remove the pain stimulus.

Function of Pain

Pain Is a Protective Mechanism

Cutaneous Pain

Originates from skin.

Deep Pain

Originates from muscles, joints, periosteum.

Visceral Pain

Originates from viscera.

Fast Pain

Sharp pain.

Slow Pain

Dull pain.

Hyperalgesia

Sensitization of pain receptors.

Physiological Response of the Body to Surgery

Increased BP and vasoconstriction, fluid retention, altered immune and metabolic responses, and tissue repair.

Complex Physiological Response

Neuroendocrine, immune, metabolic, and cardiovascular responses.

The neuroendocrine response to surgery are mediated by activation of

Activation of the Hypothalamic-Pituitary-Adrenal (HPA) axis and the Sympathetic Nervous System (SNS).

Potential Complications of Surgical Response

Excessive inflammatory response, immunosuppression, prolonged catabolism, and hemodynamic instability.

Key Stages of Tissue Healing

Inflammation, proliferation, and remodeling.

Purpose of Inflammation Stage

Contain the injury, remove damaged tissue, and prepare for repair.

Purpose of Proliferation Stage

Rebuild tissue by forming granulation tissue and new extracellular matrix (ECM).

Purpose of Remodeling Stage

Strengthen and organize the tissue.

Cellular Mechanisms of Inflammation

processes such as vasodilation, chemotaxis, and phagocytosis

Understanding physiological principles

Essential for managing injuries and promoting optimal recovery.

Fever

Elevation in body temperature

The Acute Phase Response

Systemic reaction to inflammation characterized by metabolic, hematologic, and endocrine changes.

Key Features of the Acute Phase Response

Production of acute phase proteins

Clinical Abnormalities of Acid-Base Balance

Disturbances arise from either respiratory dysfunction or metabolic disorder

Acid

a H+ donor

Base

a H+ acceptor