hap topic 1

• Anatomy


  Investigates structure of the body, body parts and their relationship to one another
• Physiology


  Studies how the body and body parts work
• Levels of organisation in the body


  • Chemicals (atoms, molecules, etc)
  • Cells
  • Tissue
  • Organs
  • Organ systems
  • Organism (human)
• Epithelial tissue


  • Covers internal and external surfaces of body
  • Has a free surface, basement membrane, no blood vessels extending into epithelium
• Functions of epithelial tissue

  • Protect underlying tissues
  • Barrier to entry of substances
  • Permit passage of substances
  • Secrete substances
  • Absorb substances
• Types of epithelial tissue

  • Simple squamous
  • Simple cuboidal
  • Simple columnar
  • Transitional
  • Pseudostratified columnar
  • Stratified squamous
• Connective tissue


  • Cartilage: Tough and flexible, provide mechanical strength, withstand compression &/or stretching
  • Bone: Hard, calcified matrix, provide structural support, calcium storage
  • Blood: Mixture of red and white blood cells surrounded by plasma, transport antibodies, respiratory gases, nutrients and wastes
  • Adipose tissue: Fat cells full of lipids, energy storage, cushion and thermal insulation
• Membrane


  Thin layer of tissue that enclose or lies on a structure or cavity
• Types of membranes

  • Mucous membrane: Lines digestive, respiratory and urinary tracts, protection, absorption and secretion
  • Serous membrane: Lines sealed, internal cavities, secrete thin serous fluid, prevent damage from abrasion
  • Cutaneous membrane: Skin, protection, barrier, prevent H2O loss
  • Synovial membrane: Lining joint cavities, joint lubrication
• Homeostasis


  Maintenance of a relatively constant environment within the body, usually within a narrow normal range, fluctuating around a set point
• Negative feedback


  A regulatory mechanism where a change in a physiological variable triggers a response that reverses the initial change, aiding in maintaining a stable internal environment (homeostasis)
• Positive feedback


  A deviation from the normal set point, and it amplifies the deviation further away from that value in the same direction
• muscle tissue

  • Contraction to bring about movement (skeletal, cardiac, smooth)
• Nervous tissue:

  • Forms part of nervous system, transmit nerve impulses
• simple squamous

  • lining of heart and blood vessels
  • alveoli of lungs
  • regulate permeability
• simple cuboidal

  • kidney tubules
  • ovary surfaces
  • absorption and secretion
• simple columnar

  • lining of stomach and intestines
  • absorption and secretion
• transitional

  • lining of the bladder
  • stretches to accommodate change in urinary volume
• pseudostratified columnar

  • lining of trachea and bronchi
  • secret mucus, propel mucus out of respiratory tract
• stratified squamous

  • non-keratinised: lining of oesophagus
  • keratinised: outer layer of skin
  • protect against abrasion and infection
• temperature control/ temperature levels

  
  

  • if body temperature increases above normal range, blood vessels in skin dilate (vasodilation), to allow more blood flow through the skin
  • this facilitates transfer of heat from body to skin, which is then lost from the skin via conduction, convection or radiation
  • sweat glands are activated, leading to increased sweat production
  • as sweat evaporates, it cools the body and help to lower the temperature back to normal range
• labor contractions during childbirth

  • during childbirth, when the fetus pushes against the cervix, it causes it stretch and stimulates the pituitary glands to secrete a hormone called oxytocin
  • oxytocin then causes uterine muscle contractions, pushing the fetus even closer to the cervix, which in turns stimulates more oxytocin production
  • this positive feedback loop continues until baby is delivered