Features Of Transport Systems Flashcards
(122 cards)
1
Q
What are the three factors that determine the need for a transport system?
A
Size, SA: Vol ratio, Activity levels/metabolic rate
2
Q
What is the role of transport systems in organisms?
A
Link exchange surfaces with the cells of the body
3
Q
What is an example of a transport medium in animals?
A
Blood flow and lymph system
4
Q
What is an example of a transport medium in plants?
A
Water + phloem sap
5
Q
What mechanism is used to move the transport medium within vessels?
A
Using pressure differences between parts of the system
6
Q
What is the animal example of a mechanism that moves the transport medium?
A
Heart
7
Q
What is the plant example of a mechanism that moves the transport medium?
A
Transpiration
8
Q
What is the purpose of valves in a transport system?
A
To maintain blood flow in one direction
9
Q
What are examples of valves in the animal circulatory system?
A
Atrioventricular valves, semilunar valves, pocket valves in veins
10
Q
What are respiratory pigments used for in some transport systems?
A
To increase the volume of oxygen that can be carried
11
Q
What is an example of a respiratory pigment in animals?
A
Haemoglobin
12
Q
What type of system has a closed network of tubular vessels?
A
Closed circulatory system
13
Q
What is an example of tubular vessels in animals?
A
Blood vessels - arteries, capillaries, veins
14
Q
What is an example of tubular vessels in plants?
A
Xylem and phloem
15
Q
What is a characteristic of an open circulatory system?
A
Haemolymph bathes tissues and is held in a cavity called the haemocoel
16
Q
Which organisms typically have an open circulatory system?
A
Insects and some marine creatures such as jellyfish
17
Q
How does the insect heart work?
A
Pumps haemolymph at low pressure into the haemocoel for exchange of substances
18
Q
What are the holes called through which haemolymph returns to the insect heart?
A
Ostia
19
Q
What are the two parts of the double circulatory system?
A
Pulmonary circulation and systemic circulation
20
Q
What is the function of pulmonary circulation?
A
Pumps blood from right ventricle to lungs to the left atrium
21
Q
What is the function of systemic circulation?
A
Pumps blood from the left ventricle to the body to the right atrium
22
Q
Fill in the blank: Pulmonary circulation pumps blood from the _______ to the lungs.
A
right ventricle
23
Q
Fill in the blank: Systemic circulation pumps blood from the left ventricle to the _______.
A
body
24
Q
True or False: The right atrium receives blood from the pulmonary circulation.
A
False
25
True or False: The left atrium receives blood from the systemic circulation.
False
26
What are the 5 major types of blood vessels?
* Arteries
* Arterioles
* Capillaries
* Venules
* Veins
## Footnote
These blood vessel types play distinct roles in the circulatory system.
27
What is the function of arteries?
Take blood from the heart to the arterioles
## Footnote
Arteries are responsible for transporting oxygenated blood away from the heart.
28
What do arterioles do?
Control blood flow from the arteries to the capillaries
## Footnote
Arterioles are smaller than arteries and regulate blood pressure and flow.
29
Where does the exchange of substances occur in the circulatory system?
In the capillaries
## Footnote
Capillaries are the smallest blood vessels and facilitate the exchange of oxygen, nutrients, and waste.
30
What is the role of venules?
Drain blood from the capillaries to the veins
## Footnote
Venules collect deoxygenated blood from capillaries.
31
What is the primary function of veins?
Take blood back to the heart
## Footnote
Veins carry deoxygenated blood from the body back to the heart.
32
Fill in the blank: Arteries take blood from the heart to the _______.
arterioles
## Footnote
This pathway is essential for maintaining blood circulation.
33
True or False: Capillaries link arterioles to arteries.
False
## Footnote
Capillaries link arterioles to venules, not arteries.
34
What type of blood do arteries carry?
Oxygenated blood
## Footnote
Arteries are responsible for transporting oxygen-rich blood away from the heart.
35
What is the blood pressure and flow speed like in arteries?
High blood pressure and high blood flow speed
## Footnote
This is necessary to efficiently transport blood throughout the body.
36
What is the lumen of arteries like, and why?
Narrow lumen to maintain high pressure
## Footnote
A narrow lumen helps to sustain the high pressure needed for blood flow.
37
What structural features do arteries have to cope with high pressure?
Thick elastic layer and muscle layer
## Footnote
These layers help prevent the vessel from bursting due to high pressure.
38
How does blood move through arteries?
Due to heart contractions
## Footnote
The force generated by the heart's contractions propels blood through the arteries.
39
What type of blood do veins carry?
Deoxygenated blood
## Footnote
Veins transport blood that has a lower oxygen content back to the heart.
40
What is the blood pressure and flow speed like in veins?
Low blood pressure and low blood flow speed
## Footnote
This is characteristic of veins as they return blood to the heart.
41
What is the lumen of veins like, and why?
Wide lumen to prevent slowing blood flow
## Footnote
A wider lumen allows for smoother and faster blood return to the heart.
42
What structural features do veins have?
Thin elastic layer and muscle layer, pocket valves
## Footnote
These features help maintain blood flow and prevent backflow.
43
How do blood movements occur in veins?
Due to muscle movements and gravity
## Footnote
The contraction of surrounding muscles and gravity assist in pushing blood back to the heart.
44
What is the oxygenation level of blood in capillaries?
Decreased oxygenation
## Footnote
Capillaries are where oxygen is exchanged with tissues.
45
What is the blood pressure and flow speed like in capillaries?
Very low blood pressure and blood flow speed
## Footnote
Low pressure allows for efficient gas and nutrient exchange.
46
What is the diameter of capillaries like?
Tiny lumen diameter
## Footnote
The small size facilitates the exchange of substances with surrounding tissues.
47
What structural features do capillaries lack?
Elastic layer and muscle layer
## Footnote
Capillaries are composed only of an endothelium layer, allowing for thin walls conducive to exchange.
48
How thick is the wall of capillaries?
One cell thick
## Footnote
This minimal thickness is crucial for effective diffusion of gases and nutrients.
49
Do capillaries have valves?
No valves
## Footnote
The absence of valves is appropriate due to the low pressure in capillaries.
50
How does blood move through capillaries?
Due to heart contractions
## Footnote
Blood flow in capillaries is influenced by the pumping action of the heart.
51
Why are valves necessary in veins?
To prevent back flow
## Footnote
Valves help maintain unidirectional blood flow despite lower pressure in veins.
52
What is the structure of the mammalian heart?
A muscular double pump that creates pressure to move blood and separates the flow of oxygenated and deoxygenated blood.
53
What are the three layers of tissue in the heart?
* Epicardium (smooth outer layer)
* Myocardium (thick muscular middle layer made of cardiac muscle)
* Endocardium (smooth lining of heart chambers)
54
Why does the outer layer of the heart need to be smooth?
Enables the heart to move freely within the pericardial coelom and reduces friction.
55
From which layer do the heart contractions originate?
Myocardium.
56
Why does the endocardium need to be smooth?
Allows the blood to flow freely along the tissues.
57
What is a myogenic contraction?
A contraction initiated in the muscle itself and not dependent on neural stimulation.
58
How is the heart rate controlled?
By an electrical system using nerve stimulation called the cardiac conduction system.
59
What are the four chambers of the heart?
RIGHT ATRIUM, RIGHT VENTRICLE, LEFT ATRIUM, LEFT VENTRICLE
## Footnote
The chambers are responsible for receiving and pumping blood.
60
Which side of the heart contains oxygenated blood?
LEFT
## Footnote
The left side of the heart pumps oxygenated blood to the body.
61
Which side of the heart contains deoxygenated blood?
RIGHT
## Footnote
The right side of the heart receives deoxygenated blood from the body.
62
What happens when the atria contract?
They send blood to their respective ventricles
## Footnote
This occurs simultaneously for both atria.
63
What do the ventricles do when they contract?
The Left ventricle sends blood to the body and the Right ventricle sends blood to the lungs
## Footnote
This is part of the cardiac cycle, ensuring blood circulation.
64
Why do the ventricles have thicker walls than the atria?
They pump blood out of the heart and deal with higher pressure
## Footnote
The thicker walls are necessary to withstand the pressure of blood flow.
65
Which ventricle has thicker walls, and why?
Left ventricle; it pumps blood all around the body
## Footnote
The left ventricle needs more muscle to generate higher pressure.
66
What are the major blood vessels of the heart?
Aorta, vena cava, pulmonary artery, pulmonary vein
## Footnote
These vessels play key roles in blood circulation.
67
What are the pulmonary vessels responsible for?
Taking blood to and from the lungs
## Footnote
They include the pulmonary artery and pulmonary vein.
68
What is the largest blood vessel out of the heart?
Aorta
## Footnote
It distributes oxygenated blood to the body.
69
What is the function of veins?
Take blood towards the heart
## Footnote
They carry deoxygenated blood back to the heart.
70
What is the function of arteries?
Take blood away from the heart
## Footnote
They transport oxygenated blood to the body.
71
What does the vena cava do?
Takes deoxygenated blood from the body to the right atrium
## Footnote
It plays a crucial role in returning blood to the heart.
72
What does the pulmonary artery do?
Takes deoxygenated blood from the right ventricle to the lungs
## Footnote
This process allows for gas exchange in the lungs.
73
What does the pulmonary vein do?
Takes oxygenated blood from the lungs to the left atrium
## Footnote
This vessel is essential for transporting oxygen-rich blood to the heart.
74
What does the aorta do?
Takes oxygenated blood from the left ventricle around the body
## Footnote
It is the main artery that supplies blood to the systemic circulation.
75
If atrial pressure is higher than ventricle pressure…
The atrioventricular valve opens
76
If ventricle pressure is higher then atrial pressure…
The atrioventricular valve closes
77
If ventricle pressure is higher than artery pressure…
The semilunar valves open
78
If artery pressure is higher than ventricle pressure…
The semilunar valves close
79
What is the Sinoatrial node (SAN) commonly known as?
The pacemaker
## Footnote
The SAN is a cluster of specialised cells in the right atrium that initiates the heartbeat.
80
What initiates a wave of electrical excitation in the heart?
The Sinoatrial node (SAN)
## Footnote
The SAN generates electrical impulses that spread over both atria.
81
What is the function of the heart skeleton?
Insulates the atria from the ventricles
## Footnote
This connective tissue prevents immediate transmission of electrical impulses from atria to ventricles.
82
What is the role of the Atrioventicular node (AVN)?
Receives electrical excitation from the SAN
## Footnote
The AVN is another cluster of specialised cells that allows a delay in transmission to the ventricles.
83
What is the purpose of the delay in electrical transmission from the AVN?
Ensures the atria have finished contracting before the ventricles start
## Footnote
This delay allows for proper filling of the ventricles with blood.
84
What is the bundle of His?
A bundle of nerves that transmits electrical excitation from the AVN
## Footnote
It extends down the septum to the apex of the heart.
85
How many bundles of His are there in the heart?
Two
## Footnote
There is one bundle for each side of the heart.
86
What are Purkinje fibres?
Fibres that carry the excitation wave up the walls of the ventricles
## Footnote
They ensure the ventricles contract simultaneously from the bottom upwards.
87
True or False: The ventricles contract before the atria.
False
## Footnote
The ventricles contract after the atria due to the delay caused by the AVN.
88
Fill in the blank: The excitation wave is passed up the walls of the ventricles through _______.
Purkinje fibres
## Footnote
These fibres facilitate simultaneous contraction of the ventricles.
89
What does the P wave represent in an ECG trace?
The voltage change generated by the sino-atrial node, associated with contraction of the atria
## Footnote
P waves are small due to the atria having less muscle than the ventricles.
90
What is the PR interval?
The time between the start of the P wave and the start of the QRS complex
## Footnote
It indicates the time taken for excitation to spread from the atria to the ventricles through the AVN.
91
What does the QRS complex indicate?
The depolarisation and contraction of the ventricles
## Footnote
Ventricles have more muscle than the atria, resulting in a larger amplitude than the P wave.
92
What does the T wave represent?
The repolarisation of the ventricle muscles
93
What is the ST segment?
The segment that lasts from the end of the S wave to the beginning of the T wave
94
What is the isoelectric line in an ECG trace?
The line between the T wave and P wave of the next cycle
95
True or False: The P wave has a larger amplitude than the QRS complex.
False
96
What does the P wave represent in an ECG trace?
The voltage change generated by the sino-atrial node, associated with contraction of the atria
## Footnote
P waves are small due to the atria having less muscle than the ventricles.
97
What is the PR interval?
The time between the start of the P wave and the start of the QRS complex
## Footnote
It indicates the time taken for excitation to spread from the atria to the ventricles through the AVN.
98
What does the QRS complex indicate?
The depolarisation and contraction of the ventricles
## Footnote
Ventricles have more muscle than the atria, resulting in a larger amplitude than the P wave.
99
What does the T wave represent?
The repolarisation of the ventricle muscles
100
What is the ST segment?
The segment that lasts from the end of the S wave to the beginning of the T wave
101
What is the isoelectric line in an ECG trace?
The line between the T wave and P wave of the next cycle
102
True or False: The P wave has a larger amplitude than the QRS complex.
False
103
What happens during the p-wave?
A wave of electrical excitation from the SAN causes atrial depolarisation which causes atrial contraction
104
What happens during the QRS complex?
Electrical impulses from the bundle of his and purkinje fibres cause ventricular depolarisation which causes ventricular contraction
105
How does an atrial fibrillation show on an ECG?
Rapid heart rate and lacking p-wave
106
How does a heart attack show on an ECG?
Wide QRS complex
107
How do enlarged ventricle walls show up on an ECG?
QRS complex has greater voltage change
108
How does atherosclerosis show up on an ECG?
Change in ST segments and T-wave heights
109
What happens during the T-wave and isoelectric line?
Ventricular depolarisation which causes diastole
110
Where is blood pressure highest in the circulatory system?
In the aorta and large arteries
## Footnote
This is caused by ventricle contraction pumping blood into them.
111
What happens to blood pressure as blood flows through the arterioles?
Blood pressure drops
## Footnote
This is influenced by friction from a large surface area.
112
What causes further drops in blood pressure in the capillaries?
Formation of tissue fluid, increased surface area, and friction from branching walls
## Footnote
These factors contribute to lower pressure in capillaries.
113
Why is blood pressure low in veins?
Veins don’t experience the contraction effects of ventricles
## Footnote
This results in lower pressure compared to arteries.
114
Why is blood speed faster in veins than in capillaries?
Veins have a wider lumen
## Footnote
This results in less restriction of blood flow.
115
How is blood returned to the heart from the veins?
By the massaging effect of muscles around the veins
## Footnote
Muscle contractions help propel blood back to the heart.
116
What is the primary function of hemoglobin in the blood?
To transport oxygen from the lungs to the tissues and carbon dioxide from the tissues back to the lungs.
117
True or False: The oxygen dissociation curve is a graphical representation of the relationship between oxygen saturation of hemoglobin and partial pressure of oxygen.
True
118
Fill in the blank: The shape of the oxygen dissociation curve is __________.
sigmoidal
119
What does a rightward shift in the oxygen dissociation curve indicate?
It indicates a decrease in hemoglobin's affinity for oxygen, often due to increased levels of carbon dioxide or decreased pH.
120
Which factor does NOT affect the oxygen dissociation curve?
Temperature, pH, and carbon dioxide concentration do affect it; however, the color of the blood does not.
121
What can cause a leftward shift in the oxygen dissociation curve?
Decreased carbon dioxide levels or increased pH.
122
True or False: The oxygen dissociation curve for fetal hemoglobin is shifted to the right compared to adult hemoglobin.
False
