Topic 4: Cardiovascular System Flashcards
(55 cards)
1
Q
What does this system consist of and what does it do?
A
- Heart, blood vessels, and blood
- Considered a closed system
- responsible for the Distribution of the blood to the tissues of the body
- Flows the blood through the lungs for exchange of gases
2
Q
What is this system also known as
A
Circulatory system
3
Q
Where do arteries carry the blood?
A
- Away from the heart
4
Q
Where do veins carry the blood
A
- Towards the heart
- walls are much thinner than arteries
5
Q
What do capillaries do
A
- Form the transition between arteries and veins
6
Q
What are the two parts this system is divided into and what sides of the heart do they control?
A
- Pulmonary (lung) circulation - right side
- Systemic (body) circulation - left side
7
Q
What kind of blood does the pulmonary lung recieve and from where
A
- Receives deoxygenated blood carried in veins and pumps it into the lungs to become oxygenated
8
Q
What kind of blood does the systemic circulation recieve and from where
A
- Receives oxygenated blood from the lungs and pumps it to the rest of the body
9
Q
Where is the heart located?
A
- In the middle of the thoracic cavity between rhe two lungs (mediastinum)
- The apex of the heart is to the left
10
Q
What is mediastinum?
A
- the space between the two lungs
11
Q
What is the mediastinum bounded by?
A
- thoracic inlet cranially, the diaphragm caudally , the sternum ventrally and the spinal column dorsally
12
Q
What is the hearts shape and size
A
- has a rounded cranial end called base of the heart
- the apex of the heart is more pointed and at the caudal end
- heart does not sit straight along the median plane in the animal –> it is shifted to the right and faces more dorsally
13
Q
Explain the hearts structure
A
- Is a muscular struture
- it is attached to the other thoracic structures by large arteries and pericardial sac
14
Q
What is the pericardial sac (pericardium)
A
- Membranes that surround the heart
- It isolates the heart from the body movements
- It contains fluid for lubrification
15
Q
What is lubrification and where is this done in the heart
A
- Production of natural fluids that reduces friction between the tissues and joints
- Done in the pericardium
16
Q
What are the two distinct parts of the pericardium
A
- Visceral pericardium: adherent to the outer surface of the heart –> closer to the organs
- Pericardial sac: a little loose so the heart can beat inside of it, it is not elastic so it cannot stretch if the heart becomes abnormally enlarged
- Serous Pericardium: Consists of two membranes
17
Q
What are the two membranses of the serous pericardium?
A
- Parietal layer: which lines the pericardial sac (the outer layer)
- Visceral layer: Lies directly on the surface of the heart –> closer to the organs
18
Q
What is the pericardial space
A
- The area between the two membranes and is filled with pericaridal fluid
19
Q
What are the functions of the pericardium?
A
- Limits motion of the heart
- Keeps it from over expanding
- Reduces the friction when the heart is beating
20
Q
How many layers of the heart wall are there
A
- Three layers
- Myocardium
- epicardium
- endocardium
21
Q
Explain the endocardium and where it is
A
- Innermost layer of the heart
- Has direct contact with the blood
- Lines the chamber of the heart
- Composed of flat thin simple sqauamous epithelium and forms lining of the heart chambers
- Forms a double layer in the valves and forms the cuspid of all valves
22
Q
Explain the myocardium and where it is
A
- Placed underneath the endocardium in the heart in the middle
- It is the thickest part of the heart
- Made up of cardiac muscle
- Forms the fibrous rings around the valves
- It has muscle contractions
- It consists of muscle fibers and connective tissue
23
Q
Explain the epicardium and where it is
A
- Outermost layer of the heart
- Includes connective tissue
- Lays on the external surface of the myocardium
- considered part of the pericardium –> has fluid which helps to reduce friction
- Covers most of the outside of the heart
- preserves all of the organs
24
Q
What are the chambers of the heart and how many are there?
A
- 4 chambers
- two atria (singular: atrium)
- two ventricles
25
What do the two artia do in the heart and where are they located
- revcevie blood from veins and carry blood to the heart
- when the atria have filled with blood, their walls (composed of myocardium) contract and force blood through one way values into the ventrical
- They sit ontop of the two ventrilces and their walls form the part of the base of the heart
- The myocadrium in the artium is not very thick because it has to contract with enough blood to move into a venticle
26
What do they two ventricles do to the heart and where are they located?
- pump blood out of the heart
- When the ventricles recieve blood from the atria, the myocardium of the ventricular walls contract and force blood through one way valves to the arteries
- located below the two artia and the wall of the left ventricle forms the apex of the heart
- located posteriorly which function to pump blood out from the heart
27
How are the two artriums separated?
- The left and right artiums are separated by the internal septum
28
What is the internal septum
- a continuation of the myocardium
29
How are atria identified on the outside of the heart and what are these?
- identified by their auricles
- These are blind pouches that come off the main part of the atria and look like ear flaps
- the auricles is part of the atrium but is not the entire thing
30
What are the right and left ventricles separated by
- intervebtricular septum which is a continuation of the interatrial septum
- It is visable on the outside of the heart as the interventricular groove
31
What does the interventricular groove on the outside contain?
- Coronary blood vessals and is frequently fille dwith fat
32
Where does the right ventricle pump blood to and what is the difference from the left ventricle?
- to the pulmonary circulation through the pulmonary artery
- Blood here does not have very far to go
- Right wall is thinner than left
33
Where does the left ventricle pump blood to and what is the difference from the right ventricle?
- To the systemic circulation throught the aorta
- left ventricle wall has the most work to do pumping blood to the rest of the animals body so it is thicker
- Left ventricle wall makes up the apex of the heart
34
What is the septum of the heart and what does it do and what are the two septum
- Divides the heart into right and left sides
- It avoids mixing the oxygenated and deoxygenated blood
- interatrial septum
- interventricular septum
35
How many valves of the heart are their and what are they and what do they do
- 4 one way values that control the blood through the heart
- the valves close at specific times to prevent backflow of blood into the chamber
- 2 valves are located between the right and left atria and their respective ventricles
- and the other 2 valves are located between the right and left ventricles and they arteries they eject blood into
36
Name the 4 valves
1. Bicuspid valve "mitral valve"
- has two leaflets
- separtes the left artium and left ventricles
2. Tricuspid valve:
- has three leaflets
- separtates the right artium and right ventricle
- it opens when the pressure of the amount of blood in the right atrium forces it to open and allows blood to flow into the right ventricle
- when the pressure of the blood in the right artium exceeds the pressure of blood in the rigth artium it shuts
3. Pulmonary valve:
- blood from the right ventricle flows through it into the pulmonary circulation
- opening at the pulmonary trunk
4. Atroventricular valves:
connected to a fibourous tissues called chordae tendinae--> papillary msucles, contraction and relaxation of these muscles makes the valves open and close
5. Aortic valve:
- opening to the aorta
- left semilular valve
- blood from the left ventrical flows through it into the aorta which begins the systemic circulation
6. Semilunar valves:
- ensures blood flows only from the ventricle into the artery
- has convex side facing ventricle
37
What happems during relaxation of the ventricle
- the valve leaflets open to allow blood to flow from the artium into the ventricle
38
What happens during ventricular contatction?
- valve leaflets are forced closed
39
What is chordae tindinae
- Prvents the margins of the valve from everting back into the artium
40
How thick are the walls of the atria
- they are thin as the blood only needs to travel a short distance and are pumped into ajacent ventricle
41
Why is the wall of the left ventricle thicker than the right
- pumps blood to a greater distance at higher pressure
- left = clean oxygen blood and sends it all over the body
- right = sends deoygenated blood to the lungs
42
What is the cardiac muscle
- is a type of cell only found in the hear
- They are called cardiomyocytes (cardiocytes)
- These cells make up the myocardium
- Cells join eachother via inbtercalated discs: junctions connecting cardiomiosides and contain 1 - 2 nuceli located near the center of the cell
- Has invlountary contraction
43
How is the cardiac muscle stimulated to contract
- cardiac muscles have autoryhythemic cells
- One cardiac cell can stimulate the next cardiac cell
44
What do the vessels resmble
branching of a tree
45
What do the vessels contain
- Artery: Large vessel
- Arteroile: Smaller branch of the artery
- Capillary: Smallest blood vessels in the vascular system
46
What do capillaries unit again to form
- Venules
47
What do venules come together to form
- Larger veins
48
What are the artieries and veins have their walls formed by
1. Endothelium
- is the inner layer
- Lines the lumen of the vessels
- Provides a smooth surface and low resistance for a smooth blood flow
2. Smooth muscles & ekastic fiber
- Forms the middle layer
smooth muscle: contracts and relax to change the diameter of the vessel
elastic fiber: provides the strechablility of the vessel
3. Connective tissue and collagen fibers
- forms the outer layer
- prevents the tearing of the vessel + keep the lumen of the vessel open
49
What are the two types of arteries
1. Elastic artery: greater elastic fibres in the middle layer
- found closest to the heart
- have the the greatest ability to stretch when blood passes through them
- the aorta is the largest elastic artery in the body
2. muscular artery: great content of smooth muscles in the middle layer
- found farther away from to heart
- in this case, blood surge is not severe enough to cause damage
- they are responible to transport blood to organs and tissues --> they branch into arterioles
50
What is the circulation to the lungs called
pulmonary circulation
51
what is the functionally and anatomically seprate from the rest of the body called
systemic circulation
52
What are the two separate pumps of the heart
1. low pressure pump: dircect blood from the body to the lungs (pulmonary circulation)
2. High pressure pump: Distributes blood to the systemic circulation
53
Explain the blood flow through the heart
1. The heart recives deoxygenated blood from the systemic circulation (right atrium)
2. sent out to the pulmonary circulation for oxygenation (right ventricle)
3.recieve the freshly oxygenated blood back from the pulmonary circulation (left artium)
4. Put the oxygenated blood into systemic circulation (left ventricle)
54
Where does the blood flow journey start in the heart
vena cava which brings deoxygenated blood from the systemic circulation to the heart
55
What are peacemaker cells
- able to generate the electrical pulse
