Skip to main content
Back

Bones and Integumentary System Unit 2

Control buttons has been changed to "navigation" mode.
1/30
  • What are the three types of skeletal cartilage?

    Hyaline cartilage (support, flexibility, resilience), Elastic cartilage (contains elastic fibers, found in external ear and epiglottis), and Fibrocartilage (thick collagen fibers, great tensile strength, found in menisci and vertebral discs).
  • What is the function of the perichondrium in cartilage?

    The perichondrium is a dense connective tissue girdle that surrounds cartilage, contains blood vessels for nutrient delivery, and resists outward expansion.
  • Describe appositional and interstitial growth of cartilage.

    Appositional growth is when cells secrete matrix against the external face of existing cartilage. Interstitial growth is when chondrocytes divide and secrete new matrix from within, expanding cartilage internally.
  • How are bones classified by shape?

    Bones are classified as long (longer than wide), short (cube-shaped or sesamoid), flat (thin, flat, slightly curved), and irregular (complicated shapes like vertebrae).
  • List the seven important functions of bones.

    Support, protection, movement, mineral and growth factor storage, blood cell formation, triglyceride (fat) storage, and hormone production.
  • What are the two main textures of bone tissue?

    Compact bone is dense and solid forming the outer layer, while spongy bone is a honeycomb of trabeculae found deep to compact bone.
  • What is the structure of a typical long bone?

    A long bone has a diaphysis (shaft with compact bone surrounding medullary cavity), epiphyses (ends with external compact and internal spongy bone), and an epiphyseal line marking childhood growth.
  • What is the periosteum and its function?

    The periosteum is a white, double-layered membrane covering external bone surfaces except joints, containing osteogenic cells, blood vessels, nerves, and anchoring points for tendons and ligaments.
  • What is the endosteum?

    The endosteum is a delicate connective tissue membrane covering internal bone surfaces, including trabeculae of spongy bone and canals in compact bone.
  • Where is red marrow found and what is its function?

    Red marrow is found in trabecular cavities of spongy bone and diploƫ of flat bones; it is the site of hematopoiesis (blood cell formation).
  • What are bone markings and their categories?

    Bone markings are sites of muscle, ligament, tendon attachment, joint surfaces, and conduits for blood vessels and nerves. Categories include projections, depressions, and openings.
  • Name the five major types of bone cells.

    Osteogenic cells, osteoblasts, osteocytes, bone lining cells, and osteoclasts.
  • What are osteogenic cells?

    Mitotically active stem cells in periosteum and endosteum that differentiate into osteoblasts or bone lining cells.
  • What is the role of osteoblasts?

    Bone-forming cells that secrete unmineralized bone matrix (osteoid) including collagen and calcium-binding proteins.
  • What do osteocytes do?

    Mature bone cells in lacunae that monitor and maintain bone matrix and act as stress or strain sensors to regulate remodeling.
  • Describe osteoclasts.

    Large multinucleate cells derived from hematopoietic stem cells responsible for bone resorption.
  • What is an osteon (Haversian system)?

    The structural unit of compact bone, an elongated cylinder with concentric lamellae and a central canal containing blood vessels and nerves.
  • What are perforating (Volkmann's) canals?

    Canals that run perpendicular to central canals, connecting blood vessels and nerves of periosteum, medullary cavity, and central canal.
  • What is the composition of the organic matrix of bone?

    Organic matrix (osteoid) consists of ground substance (proteoglycans and glycoproteins) and collagen fibers, providing tensile strength and flexibility.
  • What are hydroxyapatites and their function in bone?

    Inorganic mineral salts mainly composed of calcium phosphate crystals that provide bone hardness and resistance to compression.
  • What are the main layers of the skin?

    The skin consists of the epidermis (keratinized stratified squamous epithelium), dermis (fibrous connective tissue), and the hypodermis (subcutaneous adipose tissue).
  • Name the five layers of the epidermis.

    Stratum basale, stratum spinosum, stratum granulosum, stratum lucidum (only in thick skin), and stratum corneum.
  • What are the four main cell types in the epidermis?

    Keratinocytes, melanocytes, dendritic (Langerhans) cells, and tactile (Merkel) cells.
  • What is the function of melanocytes?

    Produce melanin pigment, which protects keratinocyte nuclei from UV damage by forming pigment shields.
  • Describe the papillary layer of the dermis.

    Areolar connective tissue with collagen and elastic fibers, containing capillary loops, Meissner's corpuscles (touch receptors), and free nerve endings (pain receptors).
  • What are cleavage lines in the dermis?

    Patterns of collagen fiber orientation in the reticular dermis that influence surgical incision healing and skin tension.
  • What are the two main types of sweat glands?

    Eccrine (merocrine) sweat glands for thermoregulation and apocrine sweat glands found in axillary and anogenital areas, producing viscous sweat.
  • What is the function of sebaceous glands?

    Secrete oily sebum that softens hair and skin and has bactericidal properties; most develop from hair follicles.
  • What are the three types of skin cancer?

    Basal cell carcinoma (least malignant), squamous cell carcinoma (can metastasize), and melanoma (most dangerous, cancer of melanocytes).
  • What is the 'Rule of Nines' used for?

    A method to estimate the volume of fluid loss and extent of burns by dividing the body surface into regions representing 9% or multiples thereof.