Anatomy: Structures and Organization

• Anatomy entails the study of the body's structures and their components.

Branches of Anatomy

• Gross anatomy involves examining large structures visible without a microscope.
• Microscopic anatomy requires magnification to study tissues and cells.
• Developmental anatomy tracks structural changes from conception to maturity.
• Pathological anatomy investigates structural alterations in tissues and organs due to disease.
• Surface anatomy studies external body features in relation to deeper structures.
• Regional anatomy studies all structures within a specific body area, such as the head or arm.
• Embryology studies organismal development from fertilization to birth.
• Cytology focuses on cell structure and function.
• Histology examines tissues microscopically.
• Systemic physiology studies the functions of organ systems.
• Physiology explores how the body and its systems operate, detailing the chemical and physical processes behind life functions.

Levels of Organization

• Chemicals: Atoms and molecules.
• Cellular: Basic structural and functional units.
• Tissue: Groups of similar cells with a common function.
• Organ: Two or more tissues performing specific tasks.
• Organ System: Integrated organs working together.
• Organism: A complete living being.

Organ Systems and Their Organs

• Integumentary: Skin, hair, and nails.
• Skeletal: Bones and cartilage.
• Muscular: Skeletal muscles.
• Nervous: Brain, spinal cord, and nerves.
• Endocrine: Glands such as the thyroid and adrenal glands.
• Cardiovascular: Heart and blood vessels.
• Lymphatic: Lymph nodes and spleen.
• Respiratory: Lungs and trachea.
• Digestive: Stomach, intestines, and liver.
• Urinary: Kidneys and bladder.
• Reproductive: Ovaries and testes.

Functions of Organ Systems

• Integumentary: Protects the body and regulates temperature.
• Skeletal: Supports the body, enables movement, and produces blood cells.
• Muscular: Facilitates movement, maintains posture, and generates heat.
• Nervous: Controls body functions, coordinates activities, and responds to stimuli.
• Endocrine: Produces hormones and maintains homeostasis.
• Cardiovascular: Transports nutrients, gases, and waste products.
• Lymphatic: Provides immunity and balances fluids.
• Respiratory: Exchanges gases.
• Digestive: Absorbs nutrients and eliminates waste.
• Urinary: Eliminates waste and balances water levels.
• Reproductive: Produces gametes and offspring

Anatomical Positions

• Anatomical: Body upright, facing forward, arms at sides with palms forward, and feet slightly apart.
• Supine: Body lying on the back, face up.
• Prone: Body lying on the stomach, face down.

Directional Terms

• Cranial (cephalic): Toward the head.
• Caudal: Toward the tail.
• Proximal: Closer to the point of attachment.
• Distal: Farther from the point of attachment.
• Anterior (ventral): Front.
• Posterior (dorsal): Back.
• Medial: Toward the midline.
• Lateral: Away from the midline.
• Deep: Away from the surface.
• Superficial: Closer to the surface.
• Right and Left: Relative to the body's midline.

Body Cavities

• Cranial: Contains the brain.
• Vertebral: Contains the spinal cord.
• Thoracic: Contains the heart and lungs.
• Abdominal: Contains digestive organs.
• Pelvic: Contains reproductive and urinary organs.

Organs in Cavities

• Thoracic: Heart, lungs, and esophagus.
• Abdominal: Stomach, liver, and intestines.
• Pelvic: Bladder and reproductive organs.

Serous Membranes

• Lungs: Pleura.
• Heart: Pericardium.
• Abdominal Organs: Peritoneum.

Mediastinum

• Central thoracic cavity area located between the lungs.
• Contains the heart, trachea, esophagus, and major blood vessels.

Diaphragm

• Separates the thoracic cavity from the abdominopelvic cavity.

Body Regions

• Cervical: Neck.
• Brachial: Arm.
• Antebrachial: Forearm.
• Femoral: Thigh.
• Gluteal: Buttock.
• Sural: Calf.
• Crural: Leg.
• Pedal: Foot.

Abdominopelvic Regions

• Right hypochondriac, epigastric, left hypochondriac, right lumbar, umbilical, left lumbar, right iliac, hypogastric, and left iliac.

Abdominal Quadrants

Righ Upper (RUQ), Left Upper (LUQ), Right Lower (RLQ), and Left Lower (LLQ).

Body Planes

• Sagittal: Divides the body into left and right sections.
• Midsagittal: Creates equal left and right parts.
• Parasagittal: Creates unequal left and right parts.
• Transverse (horizontal): Divides the body into superior and inferior sections.
• Frontal (coronal): Divides the body into anterior and posterior sections.

Feedback Mechanisms

• Positive feedback amplifies the original stimulus.
• Examples include blood clotting and childbirth (oxytocin release).
• Negative feedback reduces or reverses the original stimulus.
• Examples include temperature and blood sugar regulation (insulin/glucagon).

Homeostasis Regulation

• Hypothalamus is the integrating center for body temperature.
• Endocrine system manages long-term responses.
• Nervous system produces rapid responses.
• Homeostasis is the body's maintenance of a stable internal environment.
• Failure of homeostasis can lead to disease or death.

Imaging Techniques

• X-rays, MRI, CT scans, and ultrasound.

Inflammatory Conditions

• Pericarditis: Inflammation of the pericardium.
• Pleurisy: Inflammation of the pleura.
• Peritonitis: Inflammation of the peritoneum.

Medical Conditions

• Thoracentesis: Fluid removal from the pleural cavity.
• Ascites: Fluid buildup in the abdominal cavity.
• Mediastinitis: Inflammation of the mediastinum.