Respiration Flashcards
Difference between constant and urgent needs for oxygen
Constant: baseline requirement of the body to support ongoing metabolic activities and maintain homeostasis
Urgent: arises when there is an increased demand for oxygen due to heightened metabolic activity, physical exertion, stress, or pathological conditions
Whats external respiration
oxygen is taken from external environment and CO2 is expelled from the body
Whats Internal respiration
The exchange of gases (O2 and CO2) between the blood and the bodys tissues at the cellular level
Whats Cellular Respiration
Set of metabolic processes within cells that convert nutrients (glucose) into usable energy in the form of ATP
-primary mechanism by which cells extract energy from food molecules to fuel various cellular activities
Whats external respiration across a respiratory surface
-exchange of gases between the external environment and internal environment
breathing, gas exchange in alveoli, transport of gases in the blood
Surface area: Volume ratio
in alveoli, critical determinant of respiratory efficiency that allows gas exchange in the lungs
Steps of Respiration
-ventilation- brings air into and out of lungs
-diffusion of gases across alveolar capillary membrane (epithelium)
-transport of oxygen and CO2 by blood throughout the body (perfusion)
-diffusion of gases across capillaries to and from body tissues
Properties of air and water related to oxygen content
-air is 21% oxygen, nitrogen the rest
-lower density and viscosity compared to water
-water has lower oxygen content than air, 6-7mg/L at room temp
-diffuses much slowly in water than air-higher density and viscosity
Respiration in Fish
-oxygen is obtained from water and CO2 is eliminated
Ventilation-pumping water over gills
Gills lined with thin vascularized membranes (gill lamellae), increase surface area available for gas exchange
Countercurrent exchange causes concentration gradient to be maintained (blood flows opposite direction to direction of water flow across gills)
Respiration in Insects
Tracheal System- air filled tubes (trachea) that deliver oxygen to tissues and remove CO2
-have trachea, tracheoles, and spiracles
Respiration in Birds
Air sacs: throughout the body, reservoirs that store and distribute air -reducing density of birds body (aids flight)
Ventilation Cycles: inhalation, first exhalation, exhalation, second inhalation -maximizes gas exchange efficiency
Respiration in Mammals
Lung Structure: Bronchial tree: begins with windpipe (trachea), branches into 2 primary bronchi
-lungs- bronchi divide into smaller bronchioles, then into alveoli
-alveoli are primary sites of gas exchange
pulmonary veins-oxygenated blood
Blood supply: pulmonary circulation from pulmonary arteries is deoxygenated blood
Boyles Law
P1 x V1= P2 x V2
P= pressure, V=volume
TV
Tidal Volume: air inspired or expired during normal breathing -normally 500mL
IRV
Inspiratory Reserve Volume: additional volume of air that can be forcefully inhaled -2500-3000mL
