Chapter 1: INTRO TO ANATOMY

Definition of Anatomy and Physiology

Anatomy and Physiology are foundational sciences in understanding the structure and function of the human body.

• Anatomy: The study of the structure of body parts and their relationships to one another.

• Physiology: The study of the function of the body and its parts; how the body works.

• Example: Anatomy describes the heart's chambers; physiology explains how the heart pumps blood.

Subdisciplines of Anatomy

Anatomy is divided into several subfields, each focusing on different aspects of body structure.

• Gross Anatomy: Study of structures visible to the naked eye.

• Microscopic Anatomy: Study of structures requiring magnification (e.g., histology).

• Developmental Anatomy: Study of structural changes throughout the lifespan.

Hierarchy of Organization

The human body is organized in a hierarchical manner from smallest to largest.

• Chemical Level: Atoms and molecules

• Cellular Level: Cells and their organelles

• Tissue Level: Groups of similar cells

• Organ Level: Contains two or more types of tissues

• Organ System Level: Organs that work closely together

• Organismal Level: All organ systems combined

Directional Terms

Directional terms are used to describe the locations of structures relative to other structures or locations in the body.

• Superior (cranial): Toward the head

• Inferior (caudal): Away from the head

• Anterior (ventral): Toward the front

• Posterior (dorsal): Toward the back

• Medial: Toward the midline

• Lateral: Away from the midline

• Proximal: Closer to the origin of the body part

• Distal: Farther from the origin

Anatomical Position

The anatomical position is a standard reference point for describing locations and directions on the human body.

• Body erect, facing forward

• Arms at sides, palms facing forward

• Feet slightly apart

Body Cavities

Body cavities are spaces within the body that contain vital organs.

• Dorsal cavity: Includes cranial and vertebral cavities

• Ventral cavity: Includes thoracic and abdominopelvic cavities

Abdominal Quadrants and Regions

The abdomen is divided for clinical and anatomical reference.

• Quadrants: Right upper, left upper, right lower, left lower

• Regions: Nine regions (e.g., epigastric, umbilical, hypogastric)

Organs within Organ Systems

Each organ system consists of specific organs that work together to perform functions.

• Example: The digestive system includes the stomach, intestines, liver, etc.

Organ System Functions

Organ systems maintain homeostasis and support life.

• Examples: Respiratory system exchanges gases; circulatory system transports nutrients.

Feedback Loops – Positive and Negative

Feedback mechanisms regulate physiological processes.

• Negative feedback: Reduces the effect of the stimulus (e.g., body temperature regulation).

• Positive feedback: Enhances the effect of the stimulus (e.g., blood clotting).

Membranes of the Heart, Lungs, and Peritoneal Organs

Serous membranes line body cavities and cover organs.

• Pericardium: Surrounds the heart

• Pleura: Surrounds the lungs

• Peritoneum: Surrounds abdominal organs

Chapter 5: TISSUES

Definition of Histology and Tissues

Histology is the study of tissues, which are groups of similar cells performing a common function.

• Tissue: A group of cells with similar structure and function

• Histology: Microscopic study of tissues

Tissue Types, Function, Location

There are four main tissue types in the human body, each with specific functions and locations.

• Epithelial tissue: Covers surfaces, lines cavities, forms glands

• Connective tissue: Supports, protects, binds other tissues

• Muscle tissue: Produces movement

• Nervous tissue: Transmits electrical impulses

Types of Body Membranes

Body membranes cover surfaces, line body cavities, and form protective sheets around organs.

• Mucous membranes: Line body cavities open to the exterior

• Serous membranes: Line closed body cavities

• Cutaneous membrane: The skin

Embryonic Development – Tissue Layers

During embryonic development, three primary germ layers form all tissues and organs.

• Ectoderm: Forms nervous tissue and skin

• Mesoderm: Forms muscle, bone, connective tissue

• Endoderm: Forms lining of digestive and respiratory tracts

Stem Cells

Stem cells are undifferentiated cells capable of giving rise to specialized cell types.

• Totipotent: Can become any cell type

• Pluripotent: Can become many, but not all, cell types

• Multipotent: Can become a limited range of cell types

Types of Tissue Growth and Development

Tissues grow and develop through various processes.

• Hyperplasia: Increase in cell number

• Hypertrophy: Increase in cell size

• Regeneration: Replacement of damaged tissue with the same type

• Fibrosis: Replacement with scar tissue

Two Types of Tissue Repair

Tissue repair occurs through regeneration or fibrosis.

• Regeneration: Restores normal function

• Fibrosis: Produces scar tissue, may impair function

Types of Tissue Degeneration and Death

Tissues may degenerate or die due to various causes.

• Atrophy: Shrinkage of tissue due to loss of cell size or number

• Necrosis: Premature, pathological death of tissue

• Apoptosis: Programmed cell death

Chapter 6: INTEGUMENTARY SYSTEM

Functions

The integumentary system protects the body and maintains homeostasis.

• Protection against pathogens and injury

• Regulation of body temperature

• Prevention of water loss

• Sensory reception

Layers of Skin and the Tissue Types Within

The skin consists of multiple layers, each with distinct tissue types.

• Epidermis: Stratified squamous epithelial tissue

• Dermis: Dense irregular connective tissue

• Hypodermis (subcutaneous): Adipose and areolar tissue

Layers of Epidermis

The epidermis is composed of several layers, each with specific functions.

• Stratum basale: Deepest layer, mitotically active

• Stratum spinosum: Provides strength and flexibility

• Stratum granulosum: Keratinization begins

• Stratum lucidum: Present in thick skin only

• Stratum corneum: Outermost, dead cells, protective

Nails

Nails are protective coverings on the ends of fingers and toes.

• Composed of hard keratin

• Protect distal phalanges

Hair

Hair provides protection, sensory input, and regulates temperature.

• Made of keratinized cells

• Grows from follicles in the dermis

Specific Exocrine Glands

Exocrine glands in the skin secrete substances to the surface.

• Sudoriferous (sweat) glands: Eccrine and apocrine types

• Sebaceous glands: Secrete sebum (oil)

Aging of Integument

The skin undergoes changes with aging.

• Thinning of epidermis and dermis

• Decreased collagen and elasticity

• Slower healing

Skin Disorders

Various disorders can affect the skin.

• Examples: Acne, eczema, psoriasis, skin cancer