ANATOMY & PHYSIOLOGY 241 Study of the Human Body

Structure determines Function ANATOMY & PHYSIOLOGY ANATOMY structure how form & structure relate to each other PHYSIOLOGY how anatomy functions Structure determines Function complementarity of structure & function

WAYS TO STUDY ANATOMY Microscopic Cytology Histology Gross Surface Study of cells Histology Study of tissues Gross Surface Regional Systemic Developmental

Levels of Organization

LEVELS OF ORGANIZATION Chemical or Molecular Atomsmolecules Cellular basic unit of structure and function in living things makes up organelles Tissue Level cells of similar structure & function working together to perform a specific activity 4 basic types: connective, epithelial, muscle and nerve

LEVELS OF ORGANIZATION Organ Level tissues working together to perform a specific activity Examples - heart, brain, skin, etc. Organ Systems Level groups of two or more tissues working together to perform a specific function 11 organ systems - circulatory, digestive, endocrine, urinary, immune(lymphatic), integumentary, muscular, nervous, reproductive, respiratory & skeletal Organism Level entire living things that can carry out all basic life processes-usually made up of organ systems An organism may be made of one cell

Basic Life Processes Organisms share 6 basic life processes 1. Metabolism 2. Responsiveness 3. Movement 4. Differentiation 5. Growth 6. Reproduction

Metabolism sum of all chemical processes that take place in the body Catabolism larger macromolecules are broken down into smaller subunits or monomers Anabolism larger macromolecules are formed from smaller submits.

Responsiveness ability to detect & respond to changes

Movement

Differentiation ability of cells to develop from an unspecialized cell into a specialized cell

Growth a way to increase in size

Reproduction making a whole new organism Cells able to divide and make new cells for Growth replacement

Homeostasis organ systems are interdependent share same environment composition effects all inhabitants internal environment must be kept stable maintaining stable internal environments-homeostasis dynamic equilibrium

Homeostasis varies around a Set Point average value for a variable specific for each individual determined by genetics normal ranges for a species temperature 36.7 – 37.2

HOMEOSTATIC REGULATION Autoregulation cells, tissues, organs adjust automatically to environmental changes Extrinsic Regulation Nervous System Fast Short lasting Crisis management Endocrine System Longer to react Longer lasting

Parts of Homeostatic Regulation Receptor sensitive to environmental change or stimuli Control or Integration Center receives & processes information supplied by receptor determines set point Effector cell or organ which responds to commands of control center

HOMEOSTASIS

FEEDBACK LOOPS Negative Feedback Positive Feedback output of system shuts off or reduces intensity of initiating stimulus most often seen in the body Positive Feedback initial stimulus produces a response that exaggerates or enhances its effect blood clotting & child birth

Negative Feedback

Negative Feedback Loop