[RAP0 21LEC] PRELIM: Examples of Physiological Concepts; Structural and Functional Organization; Characteristics of Life

3 Examples of Physiological Concepts

1. Muscle Contraction

2. Blood Pressure Regulation

3. Energy Metabolism

Muscle Contraction

Physiology explains how the interaction of actin and myosin filaments, powered by ATP, leads to muscle movement.

Blood Pressure Regulation

The role of baroreceptors, the autonomic nervous system, and hormones like adrenaline in maintaining stable blood pressure.

Energy Metabolism

How carbohydrates, fats, and proteins, are broken down to produce energy in the form of ATP.

Structural and Functional Organization

Overview of levels of organization in the body:

• Chemical Level

• Cell Level

• Tissue Level

• Organ Level

• Organ System Level

• Organism Level

Chemical Level

Atoms, molecules, and macromolecules

Cell Level

Basic unit of life.

Tissue Level

Groups of similar cells with common functions.

Organ Level

Structures composed of multiple tissue types

Organ System Level

Groups of organs working together.

Organism Level

The human body as a whole.

Characteristics of Life

Defining traits of living organisms:

• Organization

• Metabolism

• Responsiveness

• Growth

• Development

• Reproduction

Organization

Structures and orderly arrangement

Metabolism

Chemical processes (catabolism and anabolism).

Responsiveness

Ability to sense and react to stimuli

Growth

Increase in size or number of cells

Development

Changes in an organism over time (differentiation and growth).

Reproduction

Production of new organisms or cells.

Homeostasis

• Maintenance of a stable internal environment.

• Central to physiology, it refers to the body’s ability to maintain a stable internal environment despite external changes.

• Example: Regulation of blood glucose levels by insulin and glucagon.

• Mechanisms:

  • Negative Feedback

  • Positive Feedback

Negative Feedback

• Counteracts deviation from a set point.

• Example: Body temperature regulation

Positive Feedback

• Amplifies changes

• Example: Blood clotting, childbirth