TOPIC 11 - CARDIOVASCULAR SYSTEM Flashcards
What is the main job of cardiovascular system?
Transport and exchange nutrients, oxygen, body fluids, waste material, heat, and blood cells around the body.
Trace the flow of blood in cardiovascular system.
Heart - Elastic artery - Muscular artery - Arteriole - Capillaries - Venules - Vein - Heart
It is the innermost layer of the vessel wall next to the lumen.
Tunica intima
The epithelium present in tunica intima is composed of ?
Endothelium and subendothelium
Tunica intima is surrounded by ?
Basal lamina and loose connective tissue
Arteries have an ____ ____ ____ that separates the tunica intima from the tunica media.
internal elastic lamina
The internal elastic lamina is made of what fibers ?
Elastin fibers
The internal elastic lamina has holes to allow diffusion. True or False?
True
It is the middle layer of the vessel wall.
Tunica media
Tunica media is consists of ____ arranged layers of smooth muscle.
Concentrically
Veins have much thicker tunica media than arteries. True or False?
False
Why do arteries have much thicker tunica media than veins?
Due to more smooth muscle
Large arteries typically have an ____ ____ ____ separating tunica media and tunica adventitia.
external elastic lamina
It is the outermost layer of the vessel wall.
Tunica externa
What is the other term for tunica externa?
Tunica adventitia
Tunica externa is composed of what fibers?
Collagen and elastic fibers
What is the thickest layer in veins?
Tunica externa
Large veins may have ____ ____ bundles running longitudinally in tunica externa.
smooth muscle
Give the 3 layers of elastic artery from innermost to outermost.
- Tunica intima
- Tunica media
- Tunica externa
Give the 5 layers of muscular artery from innermost to outermost.
- Tunica intima
- Tunica elastic lamina
- Tunica media
- External elastic lamina
- Tunica externa
Give the 3 layers of arteriole.
- Tunica intima
- Tunica media
- Tunica externa
Give the 3 layers of large vein from innermost to outermost.
- Tunica intima
- Tunica media
- Tunica externa
Give the 3 layers of medium-sized vein
- Tunica intima
- Tunica media
- Tunica externa
Between large vein, medium-sized vein, and venule, which has a presence of valves?
Medium-sized vein
It nourishes the adventitia and outer tunica media.
Vasa vasorum
Large arteries and veins have small blood vessels called ____ ____ in the adventitia and outer media.
vasa vasorum
Arteries have more vasa vasorum than veins. True or False?
False
Why do veins have more vasa vasorum?
Veins have a lower content of O2 and nutrients in blood in the lumen
Give the different types of blood vessels.
- Capillaries
- Arterioles
- Venules
- Arteries
- Veins
Among the types of blood vessels, which has the smallest diameter?
Capillaries
What is the diameter of capillaries?
7-9 um
Blood vessel that allow exchange of metabolites and waste between blood and surrounding tissue.
Capillaries
Capillaries are composed of a single layer of ____ ____ rolled up into a tube.
endothelial cells
Endothelial cells of capillaries rest on ?
Basal lamina
Endothelial cells of capillaries are connected by junctions of what type?
Zona occludens type
Capillaries convert angiotensin I to ?
Angiotensin II
Capillaries can inactive things like ?
Prostaglandins and norepinephrine
Capillaries produce factors that can cause?
Constriction and relaxation of vessels
These are small cells adjacent to capillaries and venules.
Pericytes
During injury and repair, ____ can transform into other cells, forming new blood vessels and connective tissue cells.
Pericytes
What are the 3 types of capillaries?
- Continuous capillaries
- Fenestrated capillaries
- Sinusoidal capillaries or sinusoids
The differences in the three types of capillaries are based on ?
Structure of endothelium and basal lamina
What is the most common type of capillary?
Continuous (tight) capillary
Where can you find continuous capillaries ?
Muscle, connective tissue, glands and nerve tissue
Continuous capillaries have openings. True or False?
False
Continuous capillaries have no fenestrae, resulting in ?
Less exchange of substances across capillary wall
Some continuous capillaries have numerous ____ ____ in endothelium, which transport substances across endothelial cells.
pinocytotic vesicles
This type of capillary is present in organs needing rapid exchange of substances between tissues and blood.
Fenestrated capillaries
Give some organs having fenestrated capillaries.
- Kidney
- Intestine
- Endocrine organs
These are perforations or openings typically covered by thin diaphragms.
Fenestrations
The basal lamina of fenestrated capillaries is discontinuous. True or False?
False, continuous.
Substances easily cross the wall of fenestrated capillaries. True or False?
True
This type of capillary has very large diameter and twisting course.
Sinusoidal capillaries
The twisting course of sinusoidal capillaries has an effect to blood flow. What is the effect?
Blood flow moves slowly
What are the organs that have sinusoidal capillaries?
- Liver
- Bone marrow
- Spleen
- Some endocrine organs
Among the 3 types of capillary, which is very leaky ?
Sinusoidal capillaries
Substances move freely across capillary wall and into tissues because ? (Hint: 3 answers)
- There are spaces between endothelial cells.
- The endothelial cells have large fenestrae without diaphragms.
- The basal lamina is discontinuous.
Is the basal lamina of sinusoidal capillaries continuous or discontinuous?
Discontinuous
Is there a presence of diaphragm in the large fenestrae of endothelial cells of sinusoidal capillaries?
None
Capillaries branch extensively forming a ____ ____ with a huge surface area.
capillary bed (microvasculature network)
Capillary beds are great places to exchange water, ions, and macromolecules between blood and tissue because ?
- Blood flows slowly
- Surface area is huge
What are the 5 factors with regards to capillary structure that determine what stuffs move across capillary walls?
- Types of intercellular junctions
- Presence of spaces between epithelial cells
- Presence of fenestrations
- Presence of diaphragms
- Presence and number of pinocytotic vesicles
What are the factors with regards to the molecules that determine what stuffs move across capillary walls ?
- Size of molecule
- Charge of molecule
Walls of arteries/arterioles are thicker than walls of veins/venules of the same diameter. True or False?
True
How to tell the difference between arteries/arterioles and veins/venules?
Wall-to-lumen ration
What is the size of wall-to-lumen ratio of arteries/arterioles ?
Larger
Larger wall-to-lumen ratio of arteries/arterioles is because of ?
Smooth muscle in the wall
What is the size of wall-to-lumen ration of veins/venules?
Smaller
Tunica intima is thick in arterioles. True or False?
False, thin.
Tunica intima of arterioles has internal elastic lamina. True or False?
False
Tunica externa of arterioles is thick. True or False?
False, thin.
Venules have very thin walls. True or False?
True
Smaller venules are similar to ____ in terms of structure and function.
capillaries
All 3 tunics of venules are thin, but ____ is relatively the thickest.
externa
The tunica media of venules contains a few smooth muscles. True or False?
True
The tunica media of venules contains pericytes. True or False?
True
Smooth muscles in tunica media of venules are in the form of concentric rings. True or False?
False, not concentric.
Between muscular and elastic artery, which is larger?
Elastic artery
These arteries are close to heart that contributes to minimizing changes in blood pressure.
Elastic arteries
They conduct blood to different regions and organs of the body.
Arteries
This type of artery makes up most of the named arteries of the body.
Muscular/distributing arteries
Muscular arteries have obscure internal elastic lamina. True or False?
False, prominent internal elastic lamina.
The tunica media of muscular artery is thin. True or False?
False, thick.
Approximately how many layers of smooth muscle are present in tunica media of muscular artery?
Up to 40 layers
The larger the artery, the more ____ is present with the smooth muscle.
Elastin
This artery has the largest-diameter arteries in the body.
Elastic arteries
Elastic arteries include the aorta and its largest branches. True or False?
True
Elastic arteries stretch during ____ and contract during ____ diastole.
systole, diastole
The tunica intima of elastic arteries is thicker than that of muscular arteries due to ?
Thicker subendothelial layer
Tunica media of elastic arteries has numerous ____ ____ which increase with age.
elastic laminae
In between of elastic laminae of tunica media of elastic arteries, there are ?
- Smooth muscle fibers
- Reticular fibers
3, Ground substance
The tunica externa of elastic artery is relatively thick or thin?
Thin
The tunica externa of elastic artery has what components ?
- Loose connective tissue
- Nerves
- Vasa vasorum
The internal and external elastic lamina in elastic arteries are absent. True or False?
False, present but not usually visible.
They are considered capacitance vessels because at any one time they hold more than 70% of the total blood volume.
Veins
They return blood to the heart.
Vein
Among the types of veins (in relation to size), which has thin intima and media, but a relatively thick adventitia ?
Small and medium-sized veins
The tunica media of small and medium-sized veins contains a few small bundles of smooth muscle. True or False?
True
The tunica externa of small and medium-sized veins are consists of elastic fibers without smooth muscle. True or False?
False, collagen fibers.
Valves in veins are consists of folds of tunica ____ that project into the vein lumen.
intima
Veins that have valves are most numerous in the ?
Limbs
They ensure that blood flows toward the heart and does not pool in lower extremities.
Valves in veins
In large veins, tunica media is relatively thick. True or False?
False, thin.
Tunica media of large veins contains several layers of smooth muscle and abundant connective tissue. True or False?
True
Tunica adventitia of large vein is relatively thin. True or False?
False, thick.
Tunica adventitia of large veins contains abundant collagen and some bundles of smooth muscle that run longitudinally. True or False?
True
What is the purpose of the adventitial smooth muscle of large veins?
Strengthen the vessel wall to prevent excessive distension.
This system collects interstitial fluid (lymph) that leaks from blood vessels into connective tissue, and return it to blood.
Lymphatic system
Flow of lymph in lymphatic is in what form of direction?
Unidirectional
Lymphatic capillaries is composed of how many layer?
One layer of endothelial cells
Lymphatic capillaries have continuous basal lamina. True or False?
False, discontinuous.
Lymphatic capillaries merge, forming ?
Lymphatic vessels
Lymphatic vessels have very thin walls. True or False?
True
This is the inner layer of heart.
Endocardium
Endocardium is consists of endothelium and basal lamina resting on a thin layer of connective tissue. True or False?
True
It is a layer of connective tissue between endocardium and myocardium.
Subendocardium
Subendocardium contains?
- Nerves
- Blood vessels
- Branches of the conducting system of the heart
Valves are considered part of the endocardium. True or False?
True
In this layer of the heart, muscle fibers are arranged in a spiral pattern around the chambers of the heart.
Myocardium
The cardiac muscle fibers of myocardium are inserted into what type of connective tissue?
Dense fibrous connective tissue
What are the specialized cells present in the myocardium?
- Impulse-generating cells
- Conducting cells
This is the outer layer of the heart.
Epicardium
Epicardium is consists of a surface of what epithelium ?
Mesothelium
Mesothelium is what type of epithelium?
Simple squamous epithelium
Mesothelium of epicardium is supported by a thick layer of connective tissue. True or False?
False, thick.
Epicardium contains ?
- Loose connective tissue
- Large amounts of adipose tissue
- Nerves
- Blood vessels (including coronary vessels0
Consists of modified cardiac muscle cells specialized for initiation and conduction of electrochemical impulses.
Conducting system
In the conducting system of the heart, cells are distributed in a pattern that coordinates contraction of _____.
Myocardium
____ ____ are enlarged cardiac muscle fibers specialized for conducting impulses.
Purkinje fibers
Purkinje fibers have more myofibrils, and less glycogen than regular myocytes. True or False?
False, less myofibrils and more glycogen