Organization of the Human Body Flashcards
science that studies structure
Anatomy
science that studies body functions
Physiology
Anatomy (_________) determines physiology (__________)
structure,
functions
atoms -> molecules
Chemical
- cells containing organelles
- Basic unit of life
Cellular
groups of cells and surrounding material
Tissue
4 basic types pf tissues:
epithelial, connective, muscular, nervous
group of tissues performing a common function
Organ
group of tissues performing a common function
System
contains all systems of an individual
Organism
Levels of Organization
- Chemical level
- Cellular level
- Tissue level
- Organ level
- System level
- Organismal level
Life Processes
- Metabolism
- Responsiveness
- Movement
- Growth
- Differentiation
- Reproduction
the sum of all the chemical processes that occur in the body.
Metabolism
the body’s ability to detect and respond to changes.
Responsiveness
includes motion of the whole body, individual organs, single cells, and even tiny structures inside cells.
Movement
is an increase in body size that results from an increase in the size of existing cells, an increase in the number of cells, or both.
Growth
the development of a cell from an unspecialized to a specialized state.
Differentiation
refers either to the formation of new cells for tissue growth, repair, or replacement, or to the production of a new individual.
Reproduction
— Postmortem examination
— Examination and dissection of a body to determine the cause of death when life processes have not been maintained adequately.
Autopsy
is the condition of equilibrium in the body’s internal environment due to the constant interaction of the body’s many regulatory processes.
Homeostasis
Maintaining a stable internal environment
Homeostasis
Dynamic process because of many changes
Homeostasis
Examples of variable factors
1. Body temperature, Blood pressure
2. Water and nutrient levels
Homeostasis
Maintained by feedback systems
Homeostasis
cycle of events in which the status of a body condition is monitored, evaluated, changed, remonitored, reevaluated, and so on.
Feedback sys. or Feedback loop
monitored variable, such as body temperature, blood pressure, or blood glucose level, is termed a controlled condition.
Feedback sys. or Feedback loop
three basic components of Feedback sys :
receptor,
control center, and
an effector.
Components of Homeostatic Mechanisms
- Stimulus
- Receptor
- Control Center
- Effector
disrupts a controlled variable
Stimulus
recognizes the change and sends message = input (afferent pathways) to: Control Center
Receptor
that evaluates input and sends output (efferent pathway) to: Effector
Control Center
receives output and produces a response
Effector
• reverses a change in a controlled condition
• Most homeostatic control mechanisms are
negative feedback systems
• “Negative” means “opposite” (not “bad”)
• These systems reverse a change in the controlled variable, bringing it back to “normal”
— Example: high blood pressure (BP) is detected and then lowered to normal BP
Negative Feedback Systems
reverses a change in a controlled condition
Negative Feedback Systems
These systems reverse a change in the controlled variable, bringing it back to “normal”
Negative Feedback Systems
• Few homeostatic control mechanisms are of this type.
• These systems strengthen a change and must be shut down by an outside force.
- Examples:
a. Contractions of uterus cause even more
contractions at childbirth.
b. Hormonal control of ovulation.
c. Systems that control blood clotting.
POSITIVE FEEDBACK SYSTEMS