Download Blood Flow Through the Heart, Pulmonary, and Systemic Circulations

The
Cardiovascular
System
REVIEW TIME!
(This includes your “What I already
know” handout)
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Blood Flow Steps
1. Caudal/Cranial Vena
Cavae
2. Right atrium
3. Tricuspid/Right AV Valve
4. Right ventricle
5. Pulmonary/pulmonic valve
6. Pulmonary Trunk/Arteries
7. Lungs – pulmonary
circulation (CO2 out, O2 in)
8. Pulmonary Veins
9. Left atrium
10. Mitral Valve/Left AV
Valve
11. Left Ventricle
12. Aortic Valve
13. Aorta
14. Systemic circulation (O2
out, CO2 in)
ADDING MORE DETAILS TO
WHAT YOU ALREADY KNOW…
LOCATION OF
HEART:
– Between 3rd-7th ribs in
___________ animals and 2nd-6th
ribs in ___________ animals
– Lies in the ________________,
which is the space between the
right and left lungs.
• Trachea, esophagus, and other
vascular structures are also
found here
– When looking at the surface of the
heart, the only part of the atria that
are visible are the
________________ (ear-shaped
portions).
-Right Atrioventricular Valve (aka Right AV valve/Tricuspid Valve) has ___
flaps/leaflets
-Left Atrioventricular Valve (aka Left AV Valve/Mitral Valve/Bicuspid Valve)
has ___ flaps/leaflets
These valves open and close simultaneously!
The AV valves are attached to _____________ _____________, which prevent the flaps
from bending back into the atria.
_______________ muscles connect the chordae tendinae to the interventricular
septum
AV
VALVES
-Aortic valve (found at base of Aorta)
-Pulmonary/pulmonic valve (found at base of Pulmonary Trunk)
-Both valves are made of ____ leaflets
-These valves open and close simultaneously!
-They do not have chordae tendinae
SEMILUNAR
VALVES
•Each chamber is connected to a major vessel
–
–
–
–
VESSELS
Right Atrium = Vena Cavae
Right Ventricle = Pulmonary Trunk/Arteries
Left Atrium = Pulmonary Veins
Left Ventricle = Aorta
•Arteries—carry blood ________ from heart
•Veins—carry blood _________ heart
•artery -> arteriole -> capillary -> venule -> vein
•Capillaries are where gas exchange occurs
(O2 in and CO2 out at the lung capillaries, O2 out
and CO2 in at the systemic capillaries).
SA Node -> AV Node -> Bundle of His -> Purkinje Fibers
• Electrical current impulse travels in
a wavelike manner from base to
apex.
• Current spreads across both
atria from the SA node to the AV
node and causes them to
contract, pushing blood through
the AV valves into the ventricles.
• When the current reaches the
Purkinje Fibers and spreads up
the ventricular walls, the
ventricles contract from apex to
base and blood is ejected through
the pulmonic and aortic valves.
THE PERICARDIUM
-The sac the covers the heart
-The pericardium consists of an outer fibrous pericardium and an
inner serous pericardium.
• FIBROUS pericardium
– loosely attaches to the diaphragm.
• The SEROUS pericardium consists of two layers:
*The __________ pericardial layer is adhered to
the fibrous pericardium.
*The __________ pericardial layer lies on the surface
of the heart and is also known as the EPICARDIUM.
(You already know that beneath the epicardium is the
myocardium, and then the endocardium).
Between the two layers of the
serous pericardium is the
pericardial space.
This is a fluid filled cavity that
________________ the two
layers which allows the heart
to smoothly expand and
contract.
BRAND NEW INFO!
Heart:
coronary circulation
The heart has its own blood
supply, the coronary
circulation.
•The left and right
coronary arteries originate
from the root of the aorta,
right behind the aortic
valve
•Cranial and caudal vena
cavae join together with the
coronary _________ that
collects blood from coronary
circulation and returns it to
the right atrium
Fetus receives oxygen from mother through placenta
• Oxygenated blood flows from placenta to the fetus through umbilical
___________
• Blood from umbilical vein flows through liver (some bypasses liver via ductus
___________), into caudal vena cava, then into the right atrium
Fetal
Circulation
Bypasses in fetal circulation keep most of the blood out of pulmonary circulation
•Most blood from RA flows directly into LA through foramen _________
– Some blood does flow in the “normal” direction
•Blood from pulmonary artery flows into lungs or through ductus ___________
directly into aorta
Fetal
Circulation
• Blood travels through aorta to fetal systemic circulation. Deoxygenated
blood is sent back to mom via umbilical arteries that lead to the placenta
• After birth, ductus venosus constricts, and foramen ovale and ductus
arteriosus close
Fetal
Circulation