Chapter 21: The Blood Vessels
How much of the body's blood volume does the venous system contain?
2/3
The smallest vessel in the body where a 'pulse' can be felt is over an ____________.
Arteriole
What happens when blood vessels dialate?
It lowers blood pressure
High blood pressure is almost a 'given' for an obese individual for many reasons. What are some of these reasons?
More capillaries to supply adipose (fat) tissue and they are longer in length. This will increase friction and increase blood pressure.
Arteries
always carry blood away from the heart. **Best vessel to hear a pulse**
Veins
always carry blood back to the heart.
The three vessels in which you can NOT feel a pulse are the
capillaries, venules, veins
Control of our body's blood pressure comes from the cardiovascular reflex center in the medulla oblongata of the brain, and is altered as needed by a _____________________ feedback-system.
negative
The five basic blood vessels:
1. Arteries 2. Arterioles 3. Capillaries 4. Venules 5.Veins
The three things that affect the total peripheral resistance of the system are...
1. Vascular resistance 2. Blood 3. The pulmonary circuit
The pressure in a peripheral venule is only about ______% of that in the ascending aorta.
10
What is the "normal" blood pressure for a normal, healthy adult?
120/80
_________% of blood can be found in the arterial system
13%
At any given time _________ % of the blood is in the heart.
7%
__________% of blood can be found in our capillaries
7%
___________% of blood is circulating through the pulmonary circuit.
9%
Double-loop circulatory system
Consists of the pulmonary circuit, which carries blood to and from the lungs. And the systemic circuit, which carries blood to and from the rest of the body.
Why would the bottom number be lower? What IS this number?
Diastole is measuring the pressure inside the arteries when the ventricles are relaxing.
The 'bottom' number when taking and writing a blood pressure number is called the ____________ number.
Diastolic
What happens when blood vessels constrict?
It raises blood pressure
Control of our body's blood pressure comes from the cardiovascular reflex center in the ______________________ of the brain.
Medulla oblongata
There is always an exception to the rule. Arteries USUALLY carry oxygenated blood. Veins USUALLY carry deoxygenated blood back to the heart. The ______________ __________________ is the exception.
Pulmonary loop
Blood pressure is normally taken with a ____________________.
Sphygmomanometer
Why would the top number be higher? What IS this number?
Systole is measuring the pressure inside the arteries when the ventricles contract.
The 'top' number when taking and writing a blood pressure number is called the __________________ number.
Systolic
Blood vessels
The cardiovascular system is comprised of the heart, the _____________________, and the blood.
Why is it better to take blood pressure over the left brachial artery rather than the right?
The left brachial artery is closer to the heart, so the blood pressure is normally higher and more accurate.
Venules
The smallest of the vessels carrying deoxygenated blood back to the heart.
What causes varicose veins?
The valves in the veins stop working causing backflow of blood into the veins.
Veins contain ____________ to prevent backflow of blood.
Valves
Vascular resistance
Vascular resistance between blood and vessel walls. The amount of friction depends on two things... vessel length vessel diameter
Hormones that regulate blood pressure
angiotensin, epinephrin, ADH, ANP
The interoceptors that are found in the large arteries such as the ________________ (largest artery) and the carotid arteries which that are constantly monitoring blood pressure are called _______________.
aorta baroreceptors
Pulmonary arteries are still considered arteries because they are going _______ from the heart.
away
Severe dehydration
causes high blood pressure
Slight dehydration
causes low blood pressure
Inferior vena cava
collects systemic blood from all structures inferior to the diaphram.
Superior vena cava
collects systemic blood from the head, chest, and upper limbs.
Baroreceptors
constantly monitor blood pressure in the arteries.
The vessels in the pulmonary circuit differ from those of the systemic circuit in that PULMONARY ARTERIES carry....
deoxygenate blood to the lungs
Systole =
depolarization = contraction
Diastole =
depolarization = relaxation
Valves
folds f the internal lining of the vessel, to prevent backflow of blood.
The pulmonary circulation is a system of arteries and veins that transport blood between the ____________ and the _____________.
heart lungs
The blood pressure in the arterial system is ____________
higher.
Blood viscosity
is affected by the amount of water vs. formed elements
Turbulence
is caused from irregular surfaces, sudden changes in vessel diameter, plaque deposits, etc.
The blood pressure in the venous system is _____________
lower
All SYSTEMIC ARTERIES carry _______________ blood away from the heart.
oxygenated
The PULMONARY VEINS carry...
oxygenated blood back to the heart.
Antidiuretic hormone
raise blood pressure by increasing the amount of fluid in the body
Epinephrine
raise blood pressure by increasing the heart rate.
It begins at the _________________ and ends at the ____________.
right ventricle left atrium
Capillaries
smallest vessels whose walls permit exchange of oxygen and carbon dioxide between our cells and the blood stream. The walls of these vessels are composed of a single layer of simple squamous epithelial tissue. **smallest blood vessel**
Blood pressure is affected by....
the resistance of the blood through the vessels.
Viscosity
thickness of blood
Pulmonary veins are still considered arteries because they are going ____________ the heart.
toward
All SYSTEMIC VEINS carry __________ blood towards the heart.
towards
Arterioles
very small branches of the arteries. **smallest place you can feel a pulse**
The largest artery in the body is the _____________.
Aorta
When feeling for a pulse, you usually apply pressure over an ______________ in the wrist or neck.
Artery
Blood pressure is normally taken with a sphygmomanometer over the __________________ artery in the lest arm.
Brachial
The arterial system
a high pressure system due to the force of the heart pushing blood through miles of vessels.
The venous system
a low pressure system that contains almost 2/3 of the body's blood volume.
