Transcript Respiration Review

Respiration Review
Air bulk flow
caused by lungs
From air in lungs
to red blood cells
Blood bulk flow
caused by heart
From red blood
cells to body cells
Bulk Flow: Air into Lungs
• Diaphragm allows inspiration
• Intercostal muscles allow forceful expiration
Diffusion of oxygen into Blood
• The protein HEMOGLOBIN
binds the oxygen tightly so that
no diffusion occurs until the
r.b.c. is near O2 deprived body
cells
Bulk Flow: Blood carries O2 to
Body Cells
The Major Components of Blood
• Plasma:
– Glucose, hormones, etc.
suspended in a viscuous goo
• White Blood Cells:(leukocytes)
– Protect the cells from
infection/invasion
• Platelets:
– Clot the blood to prevent it from
spilling out when a rupture of
the fluid conduit occurs
• Red Blood Cells:(erythrocytes)
– Transport O2
– 99% of all blood cells
Red Blood Cells
• The protein “Hemoglobin”
binds to O2
• Binds CO2 more strongly
than O2
• Binds CO much more
strongly than CO2 (Carbon
Monoxide Poisoning)
• Contain no nucleus!
• Recycled every week or so
White Blood Cells
• Slip in between blood vessel cells
• Recognize and destroy foreign matter
Platelets
• Aid in blood clotting
• Recognize micro tears in blood conduits and
bind together to form a clot
How blood is transported
• Arteries:
– Structures that carry blood away from
the heart
– Rigid to take pressure of blood right out
of heart
• Capillaries:
– Very narrow and thin tubes between
arteries and veins where diffusion
occurs
– Can close down or open up to regulate
blood flow (e.g. stress, eating, etc...)
• Veins:
– Loosen to expand more (controlled by
smooth muscles)
– Store great quantities of blood
Another Look at Blood Vessels
How Blood Circulates: The Heart
The Heart
• Contraction of ventricals
– Larger of heart chambers
– Takes blood in from the atria
– Pumps blood out to the body
• Contraction of atria
– Smaller chambers
– Takes blood in from body
– Pumps blood into the
ventricals
• Coordinated beating of
atria then ventricals
Cardiac Cycle
• Right Ventrical pumps de-oxygenated blood to lungs
• Left Ventrical pumps oxygenated blood to the body cells
• Valves prevent backflow of blood
Coordination of the Beating
• Heart cells naturally beat
slowly if ATP is present
• If there was no coordination, the
heart cells would all beat randomly
(fibrillation)
• Coordinated beating occurs
because a group of cells (the
pacemaker cells) send nerve
impulses to the other cells
stimulating them to beat at the right
time
• Atria beat from top down,
pause, Ventricals beat from
bottom up
The Cardio-Pulmonary
System