Heart and Circulation
The heart is the pumps, two pumps side by side. The right side of the heart =
the left side = systemic circulation -> Body - every place but the lungs
the heart is divided into four chambers
1. Upper Chambers = atria / (sing. atrium) - receiving chambers from the
lungs or from the body.
2. Lower Chambers = ventricles - pumping chambers, sending blood out
to the body or lungs.
Series of blood vessels
Arteries - are large vessels that carry blood away from the heart. Most
arteries carry oxygenated blood but by definition go with arteries carry
blood away from the heart. Arteries branch, become smaller =
arterials. Capillaries = smallest vessels, walls are 1 cell thick,
they become in contact, or near contact with every cell in the body.
(You need oxygen, then your cell need oxygen, so that's why they try to
carry oxygen to them) Capillaries go to the small intestine and pick up
the nutrients there.
Capillaries turn into venules - small veins = capillary walls thicker.
Veins - venules become larger, = veins - carry blood to the heart.
Circulatory system connects within other organ systems - Digestive
tract, kidney, digestive system and other major organ systems.
Heart consists mostly of cardiac muscles. Two types of muscles -
skeleton and smooth or involuntary muscles. Some cardiac muscles will
extent into the aorta = major artery leaving the left ventricle.
Others tissues making up the heart includes fat tissues and connective
Each cell interconnects with several others cardiac cells. Connection
occurs in this location
Cardiac muscles combine features of both smooth and skeleton
Cardiac muscle and smooth muscles the most part is involuntary. Striated like skeletal muscle.
Section 4.3 (Review the muscles types) Chapter 8 and 5 they are
dealing with the three types of muscles.
The right side receives stale/ deoxygenated blood from the body.
Received into right atria --> Right ventricle --> lungs. This is refers to
the pulmonary circulation.
The left side receives fresh or oxygenated blood from the lungs. SO
when the left atria pumps it push it to the --> Left ventricle --> Body.
This is refers to the systemic circulation.
The two ventricles are separated by a muscular wall called septum. The heart
has four 1- way valves. This directs the flow of blood. One valves is called
1. Tricuspid or right atria ventricular - It’s called tricuspid because if we
were looking at the valve it have three valves.
2. Bicuspid, mitrial or left atria ventricular valve - If we were looking down
the valve it has two valves.
* These valves are liquids, theses only flow one direction. These valves are
support by tendons called cordae tendinae. These attach to the bottom of
each valves, the other end to papillary muscles in the ventricles.
Fig 5.4 in the textbook ~ the heart is two pumps, side by side. Upper
chamber is made of 4 chambers - receiving blood. Lower chamber - pump
into the lungs or the body. Receiving blood from two valves. Valves control
the direction into which the blood goes. With respect to the ventricles, can
anybody see the different between the left and right side? The left side is
thicker, this one pump blood to the body, that's why it’s thicker. The right side
pumps blood to the lungs, so that's why is thinner.
Semilunar valves - at the exit of the ventricles - last valve the blood passes
through leaving the heart. They are tricuspid shape. Prevent back load into
the heart and into the ventricles.
Construction of veins and arteries. Similar - but veins contain less smooth
muscles and more connective tissues.
Fig 5.2 ~ Structure of a capillary bed. There is a different in color on your test
Muscles are the one who pump the blood back to the heart. Right side of the heart goes to pulmonary circulation (lungs) and left side of
the heart goes to the body system.
Review for the Test # 3
Vessels ~ (Fig 5.2: Showing the capillaries and the veins)
There is two types of connective veins
Sphincters helps to control
The achieving of blood flow ......to the outside
Body temperature should be around 35C
What happens if you are out and you take a shot of alcohol? You feel
warm. That’s not a good thing. Because alcohol relaxes a part of your
Veins have valves. Valves direct the flow of the liquids. Veins direct the
flow of the liquids (See diagram behind test 2)
When people either X-rays or phsyco-therapies, they loss their hair,
because of cancer.
The heart is a pump, in adults there will be 5L of water. How long it will
take to circulate it around the body? 1 minute. It moves around 5
Kilometer per day. 70 barrels/day. 70 barrels is a regular amount
Fig. 5.9 and 5.12 ~ emphasis the thing he said. Three capillaries
sphincters. Supplying carbon dioxide.
Fig 5.13 ~ Lymphatic duct pick up the fat. Know what blood and
lymphatic vessels pick up.
Regulation of the heart beat
Remember cardiac muscle cells have a inherit ability to contract without
the outside stimulation. (If you were to hide cardiac muscle cells you
will see they can contract with each other)
To function properly, the part of the heart must be in orderly
sequences. By a second and a half they will communicate and beat at
the same time. They have the ability to communicate with one another.
Pace makers ~ there are three pace makers in your heart.
1. S - A node = Sino atrial node = primary pace maker. Fig 5.6 ~ Show
the SA Node which is located in the wall of the right atrium near the entrance of the (superior) vena cava. Superior is on the upper side of
the heart, and the inferior are in the lower side of the heart. SA Node
maintains the heart beat at 72 - 80 per minutes. The average heart
beat range from 72, more or least what is expected. If you are a
smoker your heart rate will be higher.
2. When this Sino going to send a signal to the secondary pace maker =
A-V Node (Atrioventricular node) AV node is located on the other side of
the right atrium. It controls the heart beat at 40 - 60 beats per minutes.
From this point the A-V Node sends a message down the septum via
specialized fibres = Bundle of His. Bundle of His is not a pace maker.
It’s just a min of transporting the message.
3. The Signal is then sent to the tertiary pace maker (The third pace
maker) = Purkinje fibres work their way up to the ventricles; they
control the heart beat at 15 to 40 beat per minutes. The ventricles
contract, systemic circulation. Which one is thicker? The left. Heart
beat may vary.
Lub ~ the first sound of the heart. Dup = Second sound
this occurs when the ventricles relax.
Lubb = Occurs when pressure forces the Atrio ventricular vales to close. If a
swishing sound is hear after the first sound that indicates the heart mummer
or leaky valve.
Standard pressure is 15 pounds (lbs.) per square inch. Mercury can be quite
Adult 120/80 110/70 Systolic/Diastolic
Systolic = maximum pressure in arteries after ventricular contraction. The
heart pump, fill the arteries and the arteries expand, so it is the maximum.
Diastolic = minimum pressure in arteries before the next heartbeat.
Hypertension or high blood pressure = 140/90 the arteries ar