Introduction to Human Anatomy

Study Notes

Human Anatomy

Scientific study of the body's structures, observable through microscopy or with the naked eye.
Term "anatomy" derives from Greek: "ana-" meaning "up" and "tome" meaning "to cut," referring to the dissection of organisms.
Gross Anatomy: Focuses on larger body structures visible without magnification, also called macroscopic anatomy.
Microscopic Anatomy: Involves observing structures that require magnification, divided into:
- Cytology: Study of cells.
- Histology: Study of tissues.

Approaches to Anatomy

Regional Anatomy: Examines interrelationships among all structures in a specific body region (e.g., abdomen).
Systemic Anatomy: Explores structures within a defined body system that work together for a specific function (e.g., muscular system).

Human Physiology

Scientific study of body chemistry and physics, focusing on how structures function to sustain life.
Emphasizes the importance of homeostasis—maintaining stable internal conditions (e.g., temperature, water content, and chemical levels).
Techniques include naked-eye observation, microscopy, and controlled lab experiments to study functions of structures and compounds.

Homeostasis

Essential for organisms to maintain a balanced internal environment.
Disruptions can affect temperatures, hydration, and chemical balance, necessitating physiological responses.

Chemical Level of Organization

Fundamental building blocks of matter include:
- Subatomic Particles
- Atoms: Smallest unit of an element, defined by:
  - Nucleus: Contains protons (positive charge) and neutrons (no charge).
  - Electron Cloud: Contains electrons (negative charge).
  - Atomic Number: Equal to number of protons and electrons.
  - Atomic Mass: Sum of protons and neutrons, with neutrons calculated as mass number minus protons.
  - Example with Carbon: Atomic number 6, 6 protons, 6 electrons, mass number 12, yielding 6 neutrons.

Molecules and Cells

Molecules: The basic chemical components of all body structures.
Cells: Basic unit of life, characterized by:
- Formation from single or multiple cells (unicellular or multicellular).
- Differentiation leading to diverse cell types.
- Small size and organized structure.
- Presence of specialized organelles to execute life processes.
- All cells are encased in a plasma membrane containing DNA for genetic information.

Cell Membrane

Separates a cell from its environment, allowing selective permeability.
Facilitates the passage of water, gases (e.g., oxygen, carbon dioxide), and nutrients calmly and efficiently.

Description

Learn about the scientific study of the body's structures, from the small ones observed with a microscope to the larger structures that can be readily seen and measured. Discover how anatomy involves the identification and description of living things' structures.