Introduction to Physiology Flashcards
Physiology
The study of functions of organisms
Structural levels of organization
- atoms/molecules
- cells
- tissues
- organs
- organ systems
- organism
External environment (what it is and examples)
Components outside of body
ex: air, nutrients, water, inorganic ions, urine, feces
Internal environment (what it is, examples, what seperates it)
components inside the body
ex: cells, fluid
Separated by epithelium (skin, lining of lungs, intestinal tract, kidney tubules)
major concept, problem, solution of internal/external environment
major concept: the human body requires contact with the external environment
Problem: not all cells are in direct contact with the external environment
Solution: fluid compartments. They allow for cell communication
Fluid compartments
Total body water (TBW): volume of water that is contained in all the body’s compartments
also includes intracellular fluid (ICF) and extracellular fluid (ECF)
Intracellular fluid (ICF)
fluid inside cells
Extracellular fluid (ECF) (includes)
fluid outside of cells
Includes: plasma (liquid noncellular portion of blood)
interstitial fluid (ISF): fluid (outside of blood) surrounding cells
Homeostasis (3 points)
- Maintenance of a relatively constant internal environment
- unifying theme of physiology
- disruption –> disease
Homeostatic control systems (what is and classes)
Regulatory responses to maintain homeostasis
- classes
- intrinsic/local controls
- extrinsic/ systemic controls
intrinsic/ local controls
-inherent in an organ
Extrinsic/ systemic controls
- the regulatory mechanism is initiated outside the organ
- uses the endocrine and/or nervous system
- coordinates response from several organs toward a common goal
Regulated variables (what they are and 5 examples)
-conditions regulated by homeostatic control
Ex: temperature, pH, salinity, dissolved gas concentration, nutrient/waste control
Set point ( what it is and examples)
- range for regulated variable that the body wants to maintain
- ex:
- body temperature: 37’ C
- Blood glucose: 100mg/dL
- Blood pH: 7.35-7.45
What happens if you go out of set point range?
Error signal
Homeostatic response (components)
- components:
- stimulus- change from set point (error signal)
- sensor: detects stimulus
- integrating center:
- receives input from receptors
- determines needed output of effectors
- effectors: receives output to respond to stimulus
Feedback (what it is and types)
Response after a change is detected
types–> negative and positive feedback
Negative feedback
Response moves the system in the opposite direction of the initial change
- Stabilizing
- more common
- Ex: body temperature, blood glucose levels
Positive feedback
response moves the system in the same direction as the initial change
- directional
- less common
- Ex: child birth, ovulation
Diabetes (what it is, results, types)
-Metabolic disease affecting blood glucose levels and urine volume
-Results: excessive hormones, excessive fluid loss, eventually affecting all body systems
Types:
-Diabetes Mellitus Type 1
-Diabetes Mellitus Type 2
-Gestational Diabetes
-Diabetes Insipidus
Diabetes Mellitus Type 1
- Inadequate insulin production
- insulin dependent
Diabetes Mellitus Type 2
- body cells lose response to insulin
- non-insulin dependent
- most common
Gestational Diabetes
temporary loss of sensitivity to insulin due to hormonal changes
Diabetes Insipidus
Inadequate anti-diuretic hormone secretion resulting in high urine volume
-rare (genetic)
How can you develop diabetes?
Obesity
- High fat content relative to lean body mass
- BMI –> 30-39 (body weight (kg)/height(m2)
- Sedentary lifestyle
