XYC002 Body Systems

• Anatomy


  (Greek anatomē, 'dissection') the branch of biology concerned with the study of the structure of organisms and their parts
• Anatomy is a branch of natural science which deals with the structural organization of living things. It is an old science, having its beginnings in prehistoric times.
• Macroscopic anatomy (gross anatomy)

  The examination of an animal's body parts using unaided eyesight. Gross anatomy also includes the branch of superficial anatomy.
• Microscopic anatomy


  Involves the use of optical instruments in the study of the tissues of various structures, known as histology, and also in the study of cells.
• Physiology


  (from Ancient Greek φύσις (physis) 'nature, origin', and -λογία (-logia) 'study of') the scientific study of functions and mechanisms in a living system.
• Levels of organization of the human body

  • Chemical level (atoms and molecules)
  • Cellular level
  • Tissue level
  • Organ level
  • System level
  • Organismal level
• Chemical level


  The simplest building blocks: subatomic particles, atoms and molecules. Examples are hydrogen, oxygen, carbon, nitrogen, calcium, and iron.
• Cell


  The smallest independently functioning unit of a living organism. Single celled organisms, like bacteria, are extremely small, independently-living organisms with a cellular structure. Humans are multicellular organisms with independent cells working in concert together.
• Tissue


  A group of many similar cells (though sometimes composed of a few related types) that work together to perform a specific function.
• Four basic types of tissue in the body

  • Epithelial tissue
  • Connective tissue
  • Muscular tissue
  • Nervous tissue
• Organ


  An anatomically distinct structure of the body composed of two or more tissue types. Each organ performs one or more specific physiological functions.
• Organ system


  A group of organs that work together to perform major functions or meet physiological needs of the body.
• Examples of organs

  • Stomach, heart, liver, lungs, and brain
• System


  Consists of related organs that have a common function.
• Organismal level


  The largest level of organization. All the systems of the body combine to make up an organism.
• Organ systems of the human body

  • Integumentary system
  • Skeletal system
  • Muscular system
  • Nervous system
  • Endocrine system
  • Cardiovascular system
  • Lymphatic system
  • Respiratory system
  • Digestive system
  • Urinary system
  • Reproductive system
• Important life processes of humans

  • Metabolism
  • Responsiveness
  • Movement
  • Growth
  • Differentiation
  • Reproduction
• Metabolism


  The sum of all the chemical processes that occur in the body.
• Responsiveness


  The body's ability to detect and respond to changes in its environment.
• Movement


  Includes motion of the whole body, individual organs, single cells, and even tiny organelles inside cells.
• Homeostasis


  The maintenance of relatively stable conditions, this ensures that the body's internal environment remains constant despite changes inside and outside the body.
• Nervous system

  Detects changes from the balanced state and sends messages in the form of nerve impulses to organs that can counteract the change.
• Endocrine system


  Corrects changes by secreting molecules called hormones into the blood.
• Cells

  For growth, repair, or replacement or the production of a new individual
• Understand the importance of homeostatic feedback systems and how imbalances are related to disorders
• Homeostasis


  Maintaining relatively stable conditions, this ensures that the body's internal environment remains constant despite changes inside and outside the body
• Each body system contributes to homeostasis in some way
• Nervous system

  Detects changes from the balanced state and sends messages in the form of nerve impulses to organs that can counteract the change
• Endocrine system


  Corrects changes by secreting molecules called hormones into the blood
• Feedback system/Feedback loop


  A cycle of events in which a condition in the body is continually monitored, evaluated, changed, remonitored or reevaluated
• Feedback system


  • 3 basic components: a receptor, a control center, an effector
• Negative feedback system


  Reverses a change in a controlled condition
• Positive feedback system


  Tends to strengthen or reinforce a change in one of the body's controlled conditions
• Describe some of the anatomical and physiological changes that occur with aging
• Describe the anatomical position and how anatomical terms are used to describe the human body
• Anatomical position


  When the subject stands erect facing the observer, with the head level and the eyes facing forward. The lower limbs are parallel and the feet are flat on the floor and directed forward, and the upper limbs are at the sides with the palms turned forward
• Prone


  Lying face down
• Supine


  Lying face up
• Directional terms


  Words that describe the position of one body part relative to another
• Directional term pairs


  • Superior/Inferior
  • Anterior/Posterior
  • Medial/Lateral
  • Proximal/Distal
  • Deep/Superficial