Chapter 23 Flashcards
external respiration aka pulmonary gas enhange what occurs
- diffusion of O2 from air in the alveoli of the lungs to blood in the pulmonary caps. and diffusion of CO2 in opposite direction.
- converts deoxygenated blood coming from the right side into oxygenated blood that returns to the left side
as blood flows through caps picks ups ___ and unloads ___
this is usually called an exhancge but not in this situation because each gas diffuses ___
O2 and CO2
independently
number of capillaries near Alveoli is ___
large
blood flows slow through caps in alveoli to pick up max
O2
Internal exchange or systemic gas exchange does what
exchanges o2 and CO2 between systemic capillaries and tissues
where does internal exhange occurand external exchange occur
it occurs in tisses throughout the boyd, external only in lungs.
in a person at rest tissue cell need only ___ of available O2 in oxygenated blood
25%
Blood from heart to lungs has ___ Po2 & ___ Pco2 and alveolar air is the opposite
low and high
blood form heart to tissues has ___ Po2 and ___ low Pco2
tissues is opposite
high and low
the lower the molecular weight the greater the
rate
Oxygen is not very ___ in water
soluble
what percent of oxygen is bound to Hb in RBC, thus only ___ “free to diffusese from capillaries o cell
- 5
1. 5
saturation of hemoglobin is linked to
parital pressure of oxygen
the greater the partial pressure the
greater the saturation
what are the four factors affecting hemoglobins affinity for oxygen
acidity pH, parital pressure of CO2, temp., BPG
