UNIT2 Lecture review

Exam Two Overview

  • The content for Exam Two includes:

    • Integumentary System

    • Bone Tissue

    • Skeletal System

    • The Skeleton

    • Axial Skeleton

    • Appendicular Skeleton

  • A study guide created by the group will assist in preparation.

Integumentary System

  • Layers of the Epidermis: Understand the five layers and their characteristics and functions:

    • Stratum Basale:

    • Bottommost layer.

    • Contains basal cells undergoing mitosis.

    • Melanocytes: Produce pigment (melanin).

      • Cancer of melanocytes is called melanoma.

      • Complete absence of pigment is termed albinism.

      • Autoimmune disease destroying melanocytes is vitiligo.

    • Merkel Cells: Fine touch receptors.

    • Stratum Spinosum:

    • Contains immune cells, specifically Dendritic cells (Langerhans cells).

    • Stratum Granulosum:

    • Appears grainy; cells begin to die.

    • Stratum Lucidum:

    • Transparent layer visible in stained slides.

    • Stratum Corneum:

    • Composed of completely dead cells filled with keratin, provides a barrier against mechanical damage.

  • Functions of the Skin:

    • Review functions including protection, temperature regulation, resistance to mechanical damage, homeostasis, and water balance.

  • Structures of the Dermis:

    • Two layers of dermis and their tissue types:

    • Papillary Layer (loose connective tissue)

    • Reticular Layer (dense irregular connective tissue)

    • Nerve Receptors in the Dermis: Examples:

    • Pacinian Corpuscle (lamellar corpuscle): Responds to deep pressure and vibration.

    • Glands:

    • Eccrine Sweat Glands: Utilize merocrine secretion; regulate body temperature.

    • Apocrine Glands: Utilize apocrine secretion; associated with scent.

    • Sebaceous Glands: Utilize holocrine secretion; produce sebum for lubrication.

    • Hair Follicle: Parts of hair include cortex, medulla, cuticle; arrector pili muscle causes goosebumps.

    • Skin Conditions: Understand terms such as nevus (mole), freckle, types of skin cancer, vitiligo, and albinism.

    • Clinical Terms:

    • Laceration (cut)

    • Contusion (bruise)

  • Vitamin D and Skin:

    • Cholecalciferol: Precursor to active vitamin D3; necessary for calcium absorption.

    • Disorders from vitamin D deficiency:

    • Rickets: In children.

    • Osteomalacia: In adults.

  • Anatomy of Hair and Nails:

    • Nails include:

    • Hyponychium: The skin beneath the nail.

    • Cuticle (Eponychium): Fold of skin at the nail base.

    • Lunula: The visible part of the nail matrix.

Bone Tissue (Chapter Six)

  • Functions of the Skeletal System:

    • Mineral storage (calcium and phosphorus).

    • Protection of internal organs.

    • Movement facilitation.

    • Hematopoiesis (blood cell production).

  • Shape Classifications of Bones:

    • Definitions:

    • Flat Bones: Thin and flattened (e.g., skull).

    • Sesamoid Bones: Small, round bones (e.g., patella).

    • Irregular Bones: Complex shapes (e.g., vertebrae).

    • Bone Markings: Definitions of specific terms include:

    • Fossa: A shallow depression.

    • Foramen: A hole or opening.

    • Meatus: A canal-like passageway.

    • Condyle: A rounded surface at a joint.

    • Trochanter: A large, bony outgrowth for muscle attachment.

  • Anatomy of Long Bone:

    • Parts include:

    • Diaphysis: Shaft of the bone.

    • Epiphysis: Ends of the bone.

    • Epiphyseal Plate/Line: Growth plate.

    • Compact Bone: Dense outer layer.

    • Medullary Cavity: Hollow center.

    • Periosteum: Surrounding connective tissue layer.

    • Endosteum: Lining of medullary cavity.

  • Microscopic Anatomy of Bone:

    • Lacuna: Small cavities for osteocytes.

    • Canaliculi: Tiny channels for nutrient exchange.

    • Types of Bone Cells:

    • Osteocyte: Mature bone cell.

    • Osteoblast: Cell responsible for bone formation.

    • Osteoclast: Cell responsible for bone resorption.

    • Osteogenic Cell: Stem cell that differentiates into osteoblasts.

  • Gross Anatomy of Flat Bone:

    • Consists of compact bone, spongy bone (termed diploe in flat bones), and another layer of compact bone.

  • Intramembranous Ossification:

    • Begins with embryonic tissue. Progresses through:

    • Development of capillaries.

    • Formation of osteoblasts and make bone by secreting a matrix that calcifies.

    • Osteoblasts convert to osteocytes.

  • Endochondral Ossification:

    • Begins with a hyaline cartilage template.

    • Involves the following stages:

    • Chondrocytes produce alkaline phosphatase, attracting calcium salts.

    • Hardening occurs as chondrocytes die; osteoblasts then remodel the area into bone.

  • Growth Processes:

    • Appositional Growth: Growth in width.

    • Interstitial Growth: Growth in length.

  • Growth Plate Parts:

    • Reserve Zone: Normal cartilage.

    • Proliferative Zone: Mitosis of chondrocytes.

    • Zone of Maturation and Hypertrophy: Maturing chondrocytes producing alkaline phosphatase.

    • Zone of Calcification: Chondrocytes die and are replaced by osteoblasts, leading to ossification.

  • Wolff's Law:

    • Bone responds to the stress placed upon it, adapting its shape and density based on the loads.

  • Bone Conditions and Injuries:

    • Familiarity with terms like osteogenesis imperfecta, fractures, and bone healing processes:

    • Hematoma Formation: Initial response to fracture.

    • Callus Formation: Soft tissue bridging bone ends.

    • Renovation: Remodeling and healing.

    • Nutrients important for bone health: Calcium, phosphorus, magnesium.

Axial Skeleton

  • Axial vs. Appendicular Skeleton:

    • Know which bones belong to each category.

  • Number of Bones: Familiarization with key numbers:

    • 14 phalanges in one hand.

    • 8 carpal bones.

    • 8 cranial bones.

    • 14 facial bones.

  • Facial Bone Names: Identify the 14 facial bones.

  • Cranial Sutures and Rib Articulations:

    • Ribs articulate with the sternum and vertebrae.

    • Distinction between true ribs (vertebrosternal) and false ribs (vertebrocostal or floating).

  • Hyoid Bone: Unique as it does not articulate with other bones.

  • Vertebra Anatomy: Know individual parts of vertebrae including body, pedicles, lamina, spinous and transverse processes.

  • Spinal Regions and Vertebrae Counts:

    • Total number of vertebrae and segments of the spine: cervical, thoracic, lumbar.

  • Appendicular Skeleton:

    • Identification of girdles:

    • Pectoral Girdle: Includes clavicle and scapula.

    • Pelvic Girdle: Comprised of ilium, ischium, pubis.

    • Important landmarks of the arms and legs:

    • Humerus: Medial and lateral epicondyles.

    • Ulna and Radius: Olecranon process and distal landmarks.

    • Tibia and Fibula: Malleolus and other key features.

  • Phalanges: Classification for hands and feet knowledge.

  • Final Notes:

    • Review key numbers multiple times throughout study materials to ensure mastery.

Study Preparation

  • Good luck with your studies and remember to revisit this comprehensive study guide for success on Exam Two!