Anatomy
Studies the structure of body parts and their relationships to one another.
Physiology
Concerns the function of the body, in other words,
... [Show More] how the body parts work and carry out their life sustaining activities. Often focuses on cellular and molecular level.
Gross or Macroscopic Anatomy
Study of large body structures visible to naked eye (ex: heart, lungs, kidneys).
Regional Anatomy
All structures in a particular region of the body, ex: abdomen, leg
Systemic Antomy
Body structure is studied system by system, ex: cardiovascular system, you would examine the heart and blood vessels of the entire body.
Microscopic Anatomy
Deals with structures too small to be seen with the naked eye.
Cytology
Studies cells of the body.
Histology
Studies microscopic tissues of the body.
Developmental Anatomy
Traces structural changes that occur throughout the life span.
Embryology
Subdivision of developmental anatomy, concerns developmental changes that occur before birth.
Principle of complementarity of structure and function
Anatomy and physiology are inseparable because function always reflects structure. What a structure can do depends on its specific form.
Levels of structural organization
-chemical
-cellular
-tissue
-organ
-organ system
-organismal
Chemical Level
Simplest level of structural hierarchy. Atoms, tiny building blocks of matter, combine to form molecules. Molecules combine to form organelles, basic components of the microscopic cells.
Cellular Level
Cells are the smallest units of living things. All cells have some common functions, but individual cells vary widely in size and shape. Cells are made up of molecules.
Tissue Level
The simplest living creatures are single cells, but in complex organisms such as human beings, the hierarchy continues on to the tissue level. Tissues consist of similar types of cells.
Four basic tissue types
-epithelium (covers body surface and protects organs)
-muscle (provides movement)
-connective (supports and protects organs)
-nervous (provides rapid internal communication by transmitting electrical impulses)
Organ Level
Extremely complex functions become possible at this level. Organs are made up of different types of tissues. Ex: stomach produce digestive juices to churn and mix food.
Organ System Level
Organs work together to accomplish a common purpose. Ex: heart and blood vessels circulate blood to carry oxygen and nutrients to all body cells.
Organismal Level
Highest level of organization, represents the sum total of all structural levels working together to keep us alive.
necessary life functions
Maintain boundaries, movement, responsiveness, digestion, metabolism, dispose of wastes, reproduction, growth
maintain boundaries
internal environment remains distinct from the external environment
Movement
contractility (ability to move by shortening)
move body parts or substances though body
Responsiveness or excitability
The ability to sense changes (stimuli) in the environment and then respond to them.
Which system is most involved with responsiveness?
Because nerve cells are highly excitable and communicate rapidly with each other, the nervous system is most involved with responsiveness. All body cells are excitable to some extent.
Digestion
Breaking down of ingested food stuffs to simple molecules that can be absorbed into the blood.
Metabolism
Broad term includes all chemical reactions that occur within body cells.
excretion
Removal of wastes from metabolism and digestion
Ex: urea, carbon dioxide, feces
reproduction
Cellular division for growth or repair
Production of offspring
growth
Increase in size of a body part or of organism
hypertrophy
increase in cell size
hyperplasia
increase in number of cells
integumentary system
Protects the body as a whole from the external environment. Forms the external body covering, and protects deeper tissues from injury. Synthesizes vitamin D, and houses cutaneous (pain, pressure, etc) receptors and sweat and oil glands.
urinary system
Eliminates nitrogenous wastes and excess ions from the body. Regulates water, electrolyte and acid base balance of the blood.
cardiovascular system
Via the blood, distributes oxygen and nutrients to all body cells and delivers wastes and carbon dioxide to disposal organs. [Show Less]