1 Introduction to Anatomy (1)

Introduction

• Instructor: Dr. Tina Chiarelli

• Institution: University of Central Florida, College of Medicine

Introduction to the Human Body

Human Anatomy

• Study of the structures of the human body

• Closely related to physiology: function of structures and systems.

Gross Anatomy

• Examines tissues bigger than 0.1 mm, typically via dissection.

Histology

• Focuses on smaller structures, including cells and tissues, as well as microscopic details of various organs.

Branches of Anatomy

• Systemic Anatomy:

  • Study of specific systems such as skeletal, muscular, nervous, cardiovascular, digestive, and respiratory systems.

• Regional Anatomy:

  • Examination by body regions, such as back, upper limb, abdomen and pelvis, head, and neck.

• Surface Anatomy:

  • Involves understanding shapes and markings on body surfaces.

Levels of Structural Organization

1. Chemical Level

   • Atoms combine to form molecules.

2. Cellular Level

   • Cells made from molecules, e.g., smooth muscle cell.

3. Tissue Level

   • Tissues consist of similar types of cells, e.g., smooth muscle tissue, cardiac tissue.

4. Organ Level

   • Different types of tissues come together to form organs, e.g., heart.

5. Organ System Level

   • Organs that work together form systems, e.g., cardiovascular system.

6. Organismal Level

   • The human organism comprises many organ systems.

Anatomical Planes and Positions

Anatomical Planes

• Frontal Plane: Divides the body into anterior and posterior.

• Median (Midsagittal) Plane: Divides the body into equal left and right parts.

• Transverse Plane: Divides the body into superior and inferior parts.

Anatomical Position

• Standing erect, facing forward with palms turned forward.

Regional and Directional Terms

• Directional Terms:

  • Used to explain locations relative to one another.

  • Proximal/Distal: Closer/Farther from trunk.

  • Superior/Inferior: Above/Below.

  • Anterior/Posterior: Front/Back.

  • Medial/Lateral: Towards midline/Away from midline.

  • Superficial/Deep: Towards surface/Away from surface.

Orientation and Directional Terms

• Anterior: Front of the body.

• Posterior: Back of the body.

• Superior: Above or higher than.

• Inferior: Below or lower than.

• Medial: Near the midline.

• Lateral: Farther from the midline.

• Proximal: Closer to attachment.

• Distal: Farther from attachment.

• Ipsilateral: Same side.

• Contralateral: Opposite sides.

Major Body Cavities

1. Dorsal Body Cavity:

   • Cranial cavity (brain)

   • Vertebral cavity (spinal cord)

2. Ventral Body Cavity:

   • Thoracic cavity (heart, lungs)

   • Abdominopelvic cavity (digestive organs, urinary bladder, reproductive organs).

Clinical Anatomy

• Field of anatomy used in medicine for diagnostics without surgery.

• Various imaging techniques provide insights into structures and functions relevant for diagnosing or treating diseases.

Diagnostic Methods

• Myelography: Contrast medium around the spinal cord.

• Barium Swallow: Studies digestive tract using barium sulfate.

• Computed Tomography (CT): Quick and accurate detection of brain, body structure, and pathology.

• Magnetic Resonance Imaging (MRI): Uses magnetic fields to differentiate tissue structures.

• Positron Emission Tomography (PET): Assessing blood flow and activity in the brain.

Tissues

• Collection of similar cells performing related functions.

1. Epithelial Tissue: For covering.

2. Connective Tissue: For support.

3. Muscle Tissue: For movement.

4. Nerve Tissue: For control and communication.

Epithelial Tissue Structures

• Types of Epithelial Cells:

  • Simple squamous, simple cuboidal, stratified squamous, and more.

• Function: Covers surfaces and lines organ cavities.

Connective Tissue Types and Functions

• Loose Connective Tissue: Supports organs.

• Adipose Tissue: Stores fat.

• Cartilage: Provides flexibility and support.

• Blood: Transports nutrients and oxygen.

• Bone: Provides structural support.

Bone Functions

• Support, movement, protection, mineral storage, blood cell formation, and energy metabolism.

Bone Production, Maintenance, and Breakdown

• Types of Cells Involved:

  • Osteogenic Cells: Stem cells.

  • Osteoblasts: Form new bone.

  • Osteocytes: Maintain bone structure.

  • Osteoclasts: Break down bone tissue.

Human Skeleton Development

Intramembranous Ossification

• Formation of flat bones from mesenchyme stem cells.

• Key in embryological development.

Endochondral Ossification

• Forms most bones via cartilage templates.

• Continues into early adulthood.

Fracture Types and Healing

1. Hematoma Formation: Initial blood clot at the fracture site.

2. Callus Formation: Internal (fibrous tissue and cartilage) and external callus forms.

3. Bone Remodeling: Restores structure.

Hormonal Regulation of Bone Growth

• Growth Hormones and Thyroid Hormones: Influence bone growth and metabolism.

• Sex Hormones: Promote growth and epiphyseal plate closure during puberty.

Disorders of Bones

• Osteoporosis: Low bone mass and increased fracture risk.

• Rickets/Osteomalacia: Deficiency-related weakening of bones.

• Osteosarcoma: Bone cancer.

Types of Joints

Fibrous Joints

• Composed of connective tissue; generally immovable.

Cartilaginous Joints

• Bones connected by cartilage; allow limited movement.

Synovial Joints

• Most movable type; contains synovial fluid.

Common Types of Synovial Joints

• Hinge Joints: Allow flexion/extension (e.g., elbow).

• Ball-and-Socket: Allow multi-directional movement (e.g., shoulder).

• Pivot Joints: Allow rotation (e.g., proximal radioulnar joint).

Joint Pathologies

1. Rheumatoid Arthritis: Autoimmune disorder affecting joints.

2. Osteoarthritis: Degenerative condition due to wear and tear.

3. Gouty Arthritis: Caused by uric acid crystal deposition in joints.

Blood Vessels

Types of Blood Vessels

1. Arteries: Carry blood away from the heart.

2. Veins: Carry blood back toward the heart.

3. Capillaries: Smallest vessels for nutrient and gas exchange.

Muscle Tissue Functions

1. Movement: Internal and external.

2. Communication: Involved in actions like speaking and typing.

3. Thermogenesis: Heat production during contractions.

Types of Muscle Tissue

1. Skeletal Muscle: Voluntary; striated.

2. Cardiac Muscle: Involuntary; found in the heart.

3. Smooth Muscle: Involuntary; found in organs and vessels.

Nervous System Overview

• Components: CNS (brain, spinal cord) and PNS (nerves).

• Functions: Sensory input, integration, motor output.

Neurons and Neuroglia

• Types of Neurons: Sensory, motor, and interneurons.

• Neuroglia Functions: Support and protect neurons, maintain homeostasis.

Reflex Arcs

• Components: Receptor, sensory neuron, integration center, motor neuron, effector.

• Allow rapid responses to stimuli.