Biology

• Anatomical position: Body is erect with the feet parallel and the arms hanging at the sides with the palms facing forward
• Anatomy


  The study of structure and the relationships among structures
• Physiology


  The study of how body structures function
• Anatomical terminology


  • Anterior/Posterior
  • Superior/Inferior
  • Medial/Lateral
  • Proximal/Distal
  • Unilateral/Bilateral
  • Superficial/Intermediate/Deep
• Body planes


  1. Sagittal

  2. Midsagittal (median)

  3. Frontal (coronal)

  4. Transverse (cross section)
• Terms of movement


  • Flexion/Extension
  • Abduction/Adduction
  • Supination/Pronation
  • Plantarflexion/Dorsiflexion
  • Inversion/Eversion
  • Medial/Lateral rotation
  • Protraction/Retraction
  • Circumduction
• Tissues


  Similar cells with a common function
• Histology


  The study of tissues
• Primary or major tissue types


  • Epithelial Tissue
  • Connective Tissue
  • Muscle Tissue
  • Nervous Tissue

  
• Tight junctions


  Close space between cells, located among cells that form linings
• Desmosomes


  Form "spot welds" between cells, located among outer skin cells

  
• Gap junctions


  Tubular channels between cells, located in cardiac muscle cells
• Epithelial tissue


  • Cover organs and the body
  • Line body cavities
  • Line hollow organs
  • Have a free surface
  • Have a basement membrane
  • Are avascular
  • Cells readily divide
  • Cells tightly packed
  • Cells often have desmosomes
  • Function in protection, secretion, absorption, and excretion

  
• Simple squamous epithelium


  • Line air sacs
  • Line blood vessels
  • Line lymphatic vessels

  
• Simple cuboidal epithelium


  • Line kidney tubules
  • Cover ovaries
  • Line ducts of some glands
• Simple columnar epithelium


  • Single layer of elongated cells
  • Nuclei usually near the basement membrane at same level
  • Sometimes possess cilia
  • Sometimes possess microvilli
  • Often have goblet cells
  • Line uterus, stomach, intestines

  
• Pseudostratified columnar epithelium


  • Single layer of elongated cells
  • Nuclei at two or more levels
  • Appear striated
  • Often have cilia
  • Often have goblet cells
  • Line respiratory passageways

  
• Stratified squamous epithelium


  • Many cell layers
  • Top cells are flat
  • Can accumulate keratin
  • Outer layer of skin
  • Line oral cavity, vagina, and anal canal

  
• Stratified cuboidal epithelium


  • 2-3 layers
  • Cube-shaped cells
  • Line ducts of mammary glands, sweat glands, salivary glands, and the pancreas

  
• Stratified columnar epithelium


  • Top layer of elongated cells
  • Cube-shaped cells in deeper layers
  • Line part of male urethra and part of pharynx

  
• Transitional epithelium


  • Many cell layers
  • Cube-shaped and elongated cells
  • Line urinary bladder, ureters, and part of urethra
• Glandular epithelium


  Cells specialized to produce and secrete substances
• Types of glandular epithelium


  • Endocrine glands (ductless, key word: hormone)
  • Exocrine glands (have ducts)
• Unicellular exocrine gland


  Composed of one cell, e.g. goblet cell
• Multicellular exocrine gland


  Composed of many cells, e.g. sweat glands, salivary glands
• Structural types of exocrine glands


  • Simple tubular
  • Simple branched tubular
  • Simple branched alveolar
  • Simple coiled tubular
  • Compound tubular
  • Compound alveolar
• Types of glandular secretions


  • Merocrine (fluid product, e.g. salivary, pancreas, sweat)
  • Apocrine (cellular product, e.g. mammary, ceruminous)
  • Holocrine (secretory products, whole cells, e.g. sebaceous)
• Connective tissue


  • Most abundant tissue type
  • Bind structures
  • Provide support and protection
  • Serve as frameworks
  • Fill spaces
  • Store fat
  • Produce blood cells
  • Protect against infections
  • Help repair tissue damage
  • Have an extracellular matrix
  • Have varying degrees of vascularity
  • Have cells that usually divide

  
• Major cell types in connective tissue


  • Fibroblasts
  • Macrophages
  • Mast cells
• Fiber types in connective tissue


  • Collagenous fibers
  • Elastic fibers
  • Reticular fibers
• Connective tissue proper


  • Loose connective tissue
  • Adipose tissue
  • Reticular connective tissue
  • Dense connective tissue
  • Elastic connective tissue
• Specialized connective tissue


  • Cartilage
  • Bone
  • Blood
• Loose connective tissue


  • Mainly fibroblasts
  • Fluid to gel-like matrix
  • Collagenous fibers
  • Elastic fibers
  • Bind skin to structures
  • Beneath most epithelia
  • Blood vessels nourish nearby epithelial cells
  • Between muscles
• Adipose tissue


  • Adipocytes
  • Cushions
  • Insulates
  • Store fats
  • Beneath skin
  • Behind eyeballs
  • Around kidneys and heart

  
• Connective Tissues


  • Abundant in dense CT
  • Hold structures together
  • Tendons, ligaments
  • Elastic fibers
  • Bundles of microfibrils embedded in elastin
  • Fibers branch
  • Elastic
  • Vocal cords, air passages
  • Reticular fibers
  • Very thin collagenous fibers
  • Highly branched
  • Form supportive networks
• Connective Tissue Types


  • Connective Tissue Proper: Loose connective tissue, Adipose tissue, Reticular connective tissue, Dense connective tissue, Elastic connective tissue
  • Specialized Connective Tissue: Cartilage, Bone, Blood
• Loose Connective Tissue


  • Mainly fibroblasts
  • Fluid to gel-like matrix
  • Collagenous fibers
  • Elastic fibers
  • Bind skin to structures
  • Beneath most epithelia
  • Blood vessels nourish nearby epithelial cells
  • Between muscles
• Adipose Tissue


  • Adipocytes
  • Cushions
  • Insulates
  • Store fats
  • Beneath skin
  • Behind eyeballs
  • Around kidneys and heart

  
• Reticular Connective Tissue


  • Composed of reticular fibers
  • Supports internal organ walls
  • Walls of liver, spleen, lymphatic organs

  
• Dense Connective Tissue


  • Packed collagenous fibers
  • Elastic fibers
  • Few fibroblasts
  • Bind body parts together
  • Tendons, ligaments, dermis
  • Poor blood supply