Module 1 Flashcards
Introduction to Physiology: Regulation & Mechanisms (45 cards)
What is physiology?
The study of how cells, tissues, organs, and systems function in living organisms.
Define Homeostasis.
The dynamic constancy of physiological variables despite external changes.
Name the three type of muscle cells
Cardiac, skeletal, and smooth muscle cells.
What is the main function of epithelial cells?
Selective secretion, absorption, and protection.
Describe a negative feedback mechanism.
A process where a change in a variable is countered to return to a set point.
Give an example of positive feedback.
Blood clot formation.
What are the components of a reflex arc?
Stimulus, receptor, afferent pathway, integrating centre, efferent pathway, and effector.
What is feedforward regulation?
Anticipatory changes in physiological processes to maintain stability.
What is the role of hormones in intercellular communication?
Hormones are chemical messengers that travel through the bloodstream to affect distant cells.
Define gap junction communication.
Direct transfer of molecules between adjacent cells via cytosol linkages.
What is a circadian rhythm?
A biological cycle that repeats approximately every 24 hours.
How does heatstroke relate to homeostasis?
Disruption of homeostasis due to excessive heat leads to failure in temperature regulation and hydration balance.
What are the three main types of connective tissue?
Loose connective tissue, dense connective tissue, and specialized connective tissues like blood, bone, and cartilage.
Differentiate between simple and stratified epithelium.
Simple epithelium is one cell layer thick; stratified epithelium has multiple layers.
What are the two primary functions of the extracellular matrix (ECM)?
It provides structural scaffolding for cells and transmits information via chemical messengers to regulate cellular activities.
Name two types of fibers found in the ECM.
Collagen fibers and elastin fibers.
What distinguishes pathophysiology from physiology?
Physiology refers to maintaining homeostasis, while pathophysiology occurs when homeostasis fails.
What is dynamic constancy in homeostasis?
Physiological variables fluctuate within a range but remain relatively constant over time.
Why does positive feedback not regulate physiological variables?
It amplifies changes, moving a system further from equilibrium.
What is the role of an effector in a reflex arc?
It carries out the response to restore homeostasis.
How is feedforward regulation different from feedback mechanisms?
Feedforward regulation anticipates changes and adjusts before they occur.
Provide an example of an organ system and its components.
The urinary system includes the kidneys, ureters, bladder, and urethra.
What tissues can compose an organ?
An organ can include epithelial, connective, muscle, and nervous tissues.
What is the difference between plasma and interstitial fluid?
Plasma is the fluid portion of blood, while interstitial fluid surrounds cells in tissues.