exercise science

• Structural levels of organisation in the human body

  • Chemical Level
  • Cellular Level
  • Tissue Level
  • Organ Level
  • System Level
  • Organismic Level
• Cell


  The basic unit of any living organism. Cells differ in their size, shape, chemical composition, etc.
• Cell structure is determined by function
• Specialised cells


  • Muscle cells have the ability to move or contract
  • Nerve cells are specialised for conductivity giving them the ability to transmit impulses
• Eukaryotic cells


  Contain a nucleus, can be single-celled or multicellular (e.g. plants, animals, fungi, algae)
• Prokaryotic cells


  Do not contain a nucleus, single-celled only (e.g. bacteria, archaea)
• Mitochondria


  Site of cellular respiration, originally a prokaryote that entered into a symbiotic relationship with another cell. Cristae contain proteins that are the site of ATP, which is referred to as energy
• Passive processes


  Occur due to Brownian motion, the random movement of all substances due to their charges
• Diffusion


  The movement of substances from where there is more of it (higher density) to where there is less of it (lower density)
• Active transport


  The movement of a substance from a lower concentration to a higher concentration using a carrier and energy
• The trillions of cells found in the human body are made up of over 200 different cell types, that vary in size, shape and function
• Tissue


  Groups of cells with similar structure and function. Organs of the body are built from tissues
• Basic tissue types


  • Epithelial
  • Nervous
  • Muscular
  • Connective
• Examples of organs


  • Heart
  • Brain
  • Skin
  • Liver
  • Pancreas
  • Kidneys
  • Intestines
  • Bladder
• The human body is a complex unit of systems that interact to allow us to breathe, eat, digest, move, react, grow and reproduce
• Homeostasis


  The maintenance of a state of physiological balance
• Negative feedback loop


  Any homeostatic process that changes the direction of the stimulus
• Positive feedback loop


  Maintains the direction of a stimulus
• Set point


  The physiological value around which the normal range fluctuates
• Anatomical position and terms


  Used to describe body parts relative to others to reduce confusion
• Anatomical terms


  • Superior
  • Inferior
  • Anterior
  • Posterior
  • Medial
  • Lateral
  • Proximal
  • Distal
  • Superficial
  • Deep
  • Palmar
  • Plantar
• Sagittal plane


  Divides the body or an organ vertically into right and left sides
• Frontal plane


  Divides the body or an organ into an anterior (front) portion and a posterior (rear) portion
• Transverse plane


  Divides the body or organ horizontally into upper and lower portions
• Functions of the circulatory system


  • Transportation
  • Thermoregulation
  • Protecting the body (immunity)
• Heart


  Situated behind the sternum, made up of four chambers: two upper atria and two lower ventricles
• Bicuspid and tricuspid valves

  Prevent blood flowing back into the atria from the ventricles
• Pulmonary circulation


  Deoxygenated blood moves from the heart to the lungs, oxygenated blood moves from the lungs to the heart
• Systemic circulation


  Oxygenated blood moves from the heart to the rest of the body, deoxygenated blood moves from the rest of the body to the heart
• Types of blood vessels

  • Artery
  • Capillary
  • Vein
• Diffusion


  The passive process by which the body exchanges gases to and from the lungs or the body's cells
• Gas exchange


  Oxygenated blood moves from the arteries to arterioles and combines into the capillaries, deoxygenated blood in the capillaries moves into the venules which then combine at the vein
• Cardiac cycle


  Involves the heart filling with blood then pumping it to the rest of the body, takes just under one second to complete and has four stages: atrial diastole, ventricular diastole, atrial systole, ventricular systole
• Blood pressure


  The pressure of blood on the walls of your arteries as your heart pumps blood around your body. Systolic pressure is experienced when blood is pumped around the system from the heart, diastolic pressure is experienced when the heart relaxes and fills with blood
• Dynamic exercise


  Increases systolic blood pressure, but diastolic pressures remain nearly identical
• Static exercise


  Increases both diastolic and systolic pressure
• Vasoconstriction and vasodilation


  Blood vessels can dilate (widen) or constrict (narrow) to redirect flow of oxygenated blood to working muscles
• Whenever blood vessels dilate in one part, they must constrict elsewhere
• As exercise commences, the nervous system causes blood vessels to contract or constrict (vasoconstriction)
• Static exercise


  Increases both diastolic and systolic blood pressure