Anatomy and Physiology 241 Chapter 1

Study Notes

Homeostasis

Refers to "unchanging," representing dynamic physiological processes.
Essential for maintaining an internal environment conducive to normal body functions.

Feedback Loops

Vital for regulating physiological systems around a set point, classified as positive or negative feedback.

Parts of a Feedback Loop

Comprised of four elements: Stimulus, Receptor (Sensor), Control, and Effector.

Negative Feedback Loop

Produces responses that counteract the initial stimulus.
Common in bodily systems, ensuring stability through minor adjustments (e.g., temperature regulation).

Positive Feedback Loop

Initiates responses that enhance the original stimulus.
Rare and unstable, can lead to rapid changes (e.g., childbirth contractions, blood clotting).

Stimulus in Feedback Loop

An event that shifts a physiological set point out of its normal range (e.g., body temperature increase).

Receptor or Sensor

Specialized area (e.g., thermoreceptors) that identifies changes in the set point.

Control in Feedback Loop

The regulatory center, often located in the brain, that maintains the set point.

Effector in Feedback Loop

The entity that executes responses to restore the set point. For example, if the body temperature exceeds normal, blood vessels dilate and sweat glands are activated.

Abnormal Feedback Loop Consequences

Can lead to diseases or disorders, as seen in blood sugar regulation issues (e.g., diabetes).

Blood Sugar Regulation

Operates as a negative feedback loop.
Managed by the pancreas through the release of hormones (Insulin and Glucagon).
Insulin lowers blood glucose by facilitating cellular uptake, while Glucagon raises blood glucose by signaling liver and muscle glycogen breakdown.

Diabetes Types

Type 1 Diabetes: Autoimmune destruction of insulin-producing pancreatic cells, necessitating insulin injections for glucose regulation.
Type 2 Diabetes: Insulin is produced but body cells show reduced responsiveness, often manageable through diet alone.

Anatomy

Means "to cut up," focusing on the body's structure, observable through dissection and examination.

Physiology

Defined as "the study of nature," concerning the functions and operations of body systems.

Levels of Organization

Hierarchical arrangement includes: Atom, Molecule or Compound, Organelle, Cell, Tissue, Organ, Organ System, and Organism.

Description

Test your knowledge on homeostasis and feedback loops with these flashcards. This quiz covers key concepts essential to understanding the internal mechanisms that maintain physiological balance in the body. Ideal for students studying Anatomy and Physiology.