The Scope of Human Physiology

A collection of flashcards covering key concepts from the lecture notes on human physiology, including definitions, mechanisms, and relationships in physiological processes.

What is physiology?

The study of how living organisms function.

What are the two ends of the spectrum that physiology encompasses?

It ranges from the study of individual molecules to complex processes involving multiple organs.

What is the significance of understanding physiology in relation to medicine?

Many disease states can be viewed as physiology 'gone wrong', making the understanding of physiology essential for practice.

How can cells be classified based on their functions?

Cells can be categorized into four major types: muscle cells, neurons, epithelial cells, and connective-tissue cells.

What is cell differentiation?

The process by which unspecialized cells transform into specialized cells for particular functions.

What are the four general types of tissues in the body?

1) Muscle tissue; 2) Nervous tissue; 3) Epithelial tissue; 4) Connective tissue.

What is homeostasis?

The maintenance of stable internal conditions in the body.

How does the body fluid compartmentalization reflect structure-function relationships?

Fluid compartments, including intracellular and extracellular fluids, maintain distinct compositions critical for cellular functions.

What happens in the case of positive feedback?

Positive feedback accelerates a process and leads to an explosive system; it is less common in physiological contexts.

What is the function of epithelial tissue?

Epithelial tissue specializes in secretion and absorption of ions and organic molecules, and offers protection.

What is a reflex arc?

The sequential pathway linking a stimulus to a response involving a receptor, afferent pathway, integrating center, efferent pathway, and effector.

What is the difference between local homeostatic responses and reflexes?

Local responses occur only in the area of the stimulus, while reflexes involve pathways with nerves or hormones.

What is acclimatization?

The improved ability to respond to an environmental stress induced by prolonged exposure without genetic changes.

What is the balance of substances concept in homeostasis?

It reflects that the total-body balance of a substance depends on net gain and loss rates, which can be positive, negative, or stable.

Describe the role of intercellular chemical messengers in homeostasis.

They allow communication between cells and play essential roles in reflexes, responses, and local regulation.

What is the importance of circadian rhythms in physiology?

Circadian rhythms help anticipate changes and optimize homeostatic responses by activating mechanisms before challenges occur.

How do feedback mechanisms contribute to homeostasis?

Negative feedback restores variables to their set points, while positive feedback amplifies processes until an end-point is reached.