Module 1

• Histology - The science deals with study of normal tissues. As prelude to pathology
• Observation – key to identifying cell type
• Pathology - study of abnormal tissues
• Abnormal tissues - tissues with altered structure and function of body, organs, tissues and cells
• Tissues - group of cells that have similar structure and intercellular materials interrelated to perform a specific function
• Tissue came from Old French word “tussu” which means “weave fabric strands
• Cytology - study of cells
• Cells - basic unit of life that composed all the living things
• Mitosis - division of a cell into two daughter cells that are genetically identical to the parent cell
• Meiosis - division of germ cells. It results in four daughter cell which are not identical to the parent cell- only one copy of each paternal and maternal chromosomes can be found in the daughter cells
• Histology – division of anatomy

  • Gross Anatomy

  Microscopic Anatomy
• Cytology - study of cells and structures
• Histology - study of groups of similar cells for performance of specific function/s
• Organology - Study of group of tissues arranged in pattern of a particular organ
• Anton Van Leeuwenhoek - Using his handheld microscope, was the first person to observe and describe living cells (16th Cent)
• Robert Hooke - An English microscopist and physicist observed a slice of cork under a microscope.

  • He discovered many small compartments-like honey comb structures which he described as cells.
  • Latin term cellule
  • 1st describe nucleus while examining RBC of salmon also discovered protozoa, bacteria, muscles, nerves, etc.
• Marcelo Malpighi (Italian anatomist) - 1st describe true units forming animal tissues using simple lenses

  • True Father of Histology
• Robert Brown - Introduce nucleus

  • Observed in epidermal cells of orchids
  • Noticed small dense centers in plant cells but function is yet unknown
• Marie Francois Bichat (1802) - French pathologist

  • Termed tissues as textures
  • Tissues: different group of cells
• Matthias Schleiden - Proposed cell theory for Plants
• Theodor Schwann - Described animals are made of cells

  • Discovered cells that form sheath surrounding nerve (1838-1839)
• Friedrich Gustav Jacob Henle - Published 1st Human Histology (1841)
• Max Schultze - 1st describe cells as mass of nucleated protoplasm (1861)
• Rudolf Virchow - Fundamental Law of Biology or Law of Virchow (1863)

  • Described human body as “cell state”
  • All diseases involved changes in normal cells
• 19th Century - Microtome, fixing, embedding & staining techniques