Anatomy and Physiology Module 1

Module 1: An Introduction to Human Anatomy and Physiology

Definition of Anatomy and Physiology

• Anatomy: study of the form, structure, and location of bodily parts
• Physiology: study of the function of bodily parts and processes involved with them

Branches of Anatomy

• Gross Anatomy: study of structures examined without a microscope
• Living Anatomy: study of parts of a living individual by inspection
• Embryology: study of the first 8 weeks of development after fertilization of a human egg
• Histology: study of microscopic structures of tissues
• Surface Anatomy: study of surface markings of the body to understand internal anatomy through visualization and palpation
• Clinical Anatomy: practical application of anatomic knowledge to clinical problem-solving

Branches of Physiology

• Human Physiology: study of the function of body systems in a well state
• Microscopic Physiology: study of minute anatomical structures on a microscopic scale, including cells and tissues
• Developmental Physiology: study of complete development of an individual from fertilization to death
• Comparative Physiology: study of diversity of functional characteristics of various kinds of organisms
• Cellular Physiology: study of activities and functions that take place in a cell to keep it alive
• Environmental Physiology: study of environment's influence on physiological function and performance
• Evolutionary Physiology: study of manner in which functional characteristics of individuals in a population have responded to natural selection

Lesson 2: Structural Organization of the Human Body

Cell Structure and Function

• Cell Membrane: semipermeable, protects, and controls entry of substances across the cell
• Nuclear membrane: double-membrane structure that surrounds the nucleus
• Nucleus: contains sub-organelles such as nucleolus, nucleosomes, and chromatin, and genetic materials
• Centrosome: produces microtubules
• Lysosome: contains digestive enzymes involved in digestion, excretion, and cell renewal processes
• Cytoplasm: jelly-like material containing cell organelles enclosed with cell membrane
• Golgi Apparatus: involved in manufacturing, storing, and transporting particles throughout the cell
• Mitochondrion: produces and releases energy
• Ribosome: site of protein synthesis
• Endoplasmic Reticulum (ER): composed of a thin, winding network of membranous sacs originating from the nucleus
• Vacuole: involved in maintaining shape and storing water, food, wastes, etc.
• Nucleopore: tiny holes present in the nuclear membrane, involved in movement of nucleic acids and proteins within the cell

Kinds of Cells Found in the Human Body

• Bone cells: give strength, support, and framework to the body
• Cartilage cells (chondrocytes): similar to bone cells but without calcium and phosphate, freely bendable
• Nerve cells: form the nervous system
• Epithelial cells: form covering layers of all organs, present in skin, scalp, respiratory tract, etc.
• Muscle cells: rich in proteins like actin and myosin, responsible for movement through contraction
• Secretory cells: present in glands, releases specific secretions containing enzymes or hormones
• Adipose cells: store fat, reduce friction in the body
• Blood cells: include red blood cells, white blood cells, and thrombocytes
• Specialized cells: include sperm cells, egg cells, stem cells, rods and cones, ciliated cells, etc.

Lesson 3: The Language of Anatomy

The Anatomical Position

• Position with the body erect, arms at the sides, and palms forward
• Position of reference for anatomical nomenclature

Body Regions

• Refers to a certain area of the body: head, neck, torso, upper extremity, and lower extremity

Anatomical Terms

• Anterior and posterior, medial and lateral, abduction and adduction, etc.

Directional Terms

• Refers to directions in the body: superior, inferior, anterior, posterior, medial, lateral, etc.

Body Planes and Sections

• Imaginary flat surfaces that pass through the body
• Sagittal plane: divides an organ or the body into right and left parts
• Mid-sagittal plane: passes through the midline of an organ or the body and divides it into equal right and left halves
• Para-sagittal plane: does not pass through the midline but divides an organ or the body into unequal halves
• Frontal or Coronal plane: divides an organ or part of the body into anterior (front) and posterior (back) portions
• Transverse or Cross-sectional or Horizontal Plane: divides an organ or body into superior (upper) and inferior (lower) portions
• Oblique Plane: passes through an organ or the body at an angle between the transverse plane and either sagittal or frontal plane

Lesson 4: Homeostasis

Homeostasis

• Stability, balance, or equilibrium within a cell or the body
• Involves constant adjustments as conditions change inside and outside the cell
• Three interdependent components of homeostasis: a receptor, integrating center, and effector

Negative Feedback

• A negative feedback loop is a reaction that causes a decrease in function
• It occurs in response to some kind of stimulus, often causing the output of a system to be lessened
• Examples: regulation of body temperature, blood sugar levels, etc.

Positive Feedback

• A positive feedback loop will increase a function
• It reinforces the change until the stimulus is removed
• Examples: childbirth, blood clotting, etc.