Chapter 7 - The Transport System Flashcards
0
Q
What process helps oxygen spread through simpler animals?
A
Diffusion, it carries oxygen to any part of the cytoplasm which needs it.
1
Q
Do simple animals possess specialised systems for the transport and distribution of materials?
A
No, due to the fact that they posses a large surface area to volume ratio meaning that no part of the cytoplasm is far away from the absorbing surface.
2
Q
Why is diffusion unpractical for larger and more complex animals?
A
As organisms increase in size and complexity so do the quantity of materials moving in and out of the body increases.
The distance the materials have to travel within the body also increases, meaning that diffusion becomes inadequate.
3
Q
What do larger organisms use in order to absorb oxygen?
A
They use a respiratory organ and a circulatory system is involved.
4
Q
What’s the blood circulatory systems role in the body?
A
It carries oxygen rapidly from lungs/gills to all parts of the body.
It also carries dissolved food and excretory products to or from specialised organs to other parts of the body.
5
Q
The circulatory system carries what, to where?
A
Blood carries oxygen from the lungs to the tissues, and Corbin dioxide from the tissues to the lungs.
6
Q
Give 2 examples of animals that lack a transport system.
A
Jellyfish and anemone.
Both are in close contact with their surroundings.
7
Q
Animals with a small surface area to volume ratio need a transport system. True or false?
A
True!
8
Q
Body fluids consist of 3 components. Name them below.
A
Blood, Tissue fluid and Lymph.
9
Q
How many litres of blood does an adult have?
A
5-6 litres of blood.
10
Q
Blood is made up of 2 components. State them.
A
Liquid part (plasma 55%) Cellular part (45%)
11
Q
The cellular blood is divided into 3 types of cells. Name them.
A
Erythrocytes - Red blood cells (44%)
Leucocytes - White blood cells (1%)
Thrombocytes - Platelets (1%)
12
Q
What is plasmas characteristics?
A
It’s a pale yellow coloured liquid.
Sticky to touch.
Made up of 90% water and 10% dissolved substances.
13
Q
What are the dissolved substances found within the plasma?
A
Mineral salts (Na, K, Mg, Ca) Digested foods (glucose, amino acids) Excretory substances (urea) Hormones (testosterone) Plasma proteins (albumen, fibrinogen, globulin)
14
Q
What does the plasma protein albumin do?
A
It makes blood sticky, similar to egg whites.
15
Q
What does the plasma protein fibrinogen do?
A
It’s important for the process of blood clotting.
16
Q
What are the functions of the plasma?
A
It transports all materials in the blood.
Plasma also forms tissue fluid and lymph.
17
Q
What are erythrocytes?
A
Red blood cells.
18
Q
Are red blood cells extremely numerous in blood?
A
Yes.
19
Q
What is the site of production of erythrocytes?
A
The soft tissue found in between bones, called the red bone marrow.
This tissue can be found in the skull, vertebra, sternum and ribs.
20
Q
What is the life span of a red blood cell?
A
4 months.
This is because they are pumped at very high speed from the heart and they die due to friction and when trying to escape through capillaries which are even thinner than red blood cells, squeezing them
21
Q
What pigment is found in dead reed blood cells?
A
Haemoglobin which is made up of iron and protein.
22
Q
What does the liver do with the haemoglobin?
A
It removes the iron part and stores it.
The remaining proteins help produce bile (important for emulsification)
23
Q
What is the structure if the red blood cells?
A
They are described are being small non-nucleated bi-concave disks.
Rather compressed from both sides, hence the concave.
24
What's erythrocytes main function?
Their main function is to carry oxygen through the body.
25
How are red blood cells adapted for their functions?
They have a large surface area for more O2 absorption.
They are thin and small so that many can fit into one capillary.
They have an elastic membrane to pass from one capillary to another.
Have no nucleus and therefore have more space for haemoglobin.
26
How would a person living at high altitudes differ from a person living in normal altitude?
People who live in higher altitudes have less oxygen present, therefor have much more red blood cells to compensate.
27
What are leukocytes?
White blood cells.
28
Which are bigger, red blood cells of white blood cells?
White blood cells are much bigger.
29
What are leukocytes involved in?
The body's immune system.
30
Where is the leukocytes site of production?
Red bone marrow. Same as red blood cells.
31
Where do white blood cells undergo a maturation process?
In the thymus gland, spleen or lymph nodes.
| Lymph glands are found in the arm pits, in the neck and in the groin
32
Do leukocytes possess a nucleus?
Yes, unlike red blood cells.
33
How many types of white blood cells are there?
5 types.
34
What is the main function of leukocytes?
To fight diseases.
| The difference between each type is how they fight.
35
What are thrombocytes?
Platelets.
36
How big are platelets?
They are the smallest cells in the blood.
37
What is the site of production for thrombocytes?
They are formed in special bone marrow cells called megakaryocytes.
38
What is the function of platelets?
Their main function is to clot blood at wounds.
39
Why is clotting blood important?
This helps to stop the bleeding and prevent any further entry of bacteria.
40
How do thrombocytes initiate their process?
When they encounter an irregular surface, such as a wound they get to work.
41
What the 3 major functions of blood?
Transport, defence and homeostasis.
42
Why is blood needed as an essential aspect of transportation?
In other for substances such as glucose to be transported into the cell, and substances such as carbon dioxide to be taken away; a medium is needed.
Blood is this medium.
43
Red blood cells carry 2 substances in order to form another substance. Name them.
Red blood cells carry oxygen and haemoglobin in order to produce oxyhemoglobin, which is a very unstable compound.
This reaction is reversible.
44
When cells respire, what do they produce?
Carbon dioxide.
45
Once this carbon dioxide is picked up by red blood cells, what does it do with it?
Red blood cells have an enzyme which combines with carbon dioxide with water to produce carbonic acid.
46
What happens to carbonic acid in the alveoli?
It is broken down and carbons dioxide is exhaled.
| Only some of the water is exhaled however.
47
What is anaemia?
A condition that is associated with red blood cells, in which the oxygen carrying capacity of blood is reduced either by:
Because few red blood cells are present.
The haemoglobin is defective.
48
Anaemia shares certain symptoms with 2 other disease, which are they?
Malaria and leukaemia.
49
What can be done to improve anaemia?
Either by taking iron tablets or food rich in iron such as vegetables.
50
What are the symptoms of anaemia?
Weak, tired and pale.
51
From where do we receive oxygen? Furthermore, to where does it go?
We receive oxygen from the alveoli and lungs.
| It goes to tissues, all cells in the body, in the form of oxyhemoglobin.
52
From where do we receive carbon dioxide? Where is it transported to?
It is given from tissues, all cells within the body.
| It goes to alveoli in lungs be means of haemoglobin and in the form of hydrogen carbonate ions in the plasma.
53
Where is food digested such as glucose and amino acids? Where do these substances end up?
Food is digested in the ileum of the small intestine.
Glucose is given to the respiring tissues and liver in the plasma.
Amino acids and vitamins are given to the liver and body tissues in plasma.
54
From where do we receive nitrogenous wastes? Where do they end up in the body? (Such as urea)
They are produced in the liver.
The kidney receives them through the plasma, to eventually form urine.
55
Where are hormones produced? and where do they eventually end up? (Insulin and testosterone)
They are produced in the endocrine glands.
The target organs are the ones to receive them, depending on the job of the substances.
56
Where is metabolic heat produced and where is it transported to?
Heat is produced by the liver and muscles.
Heat is transported by means of blood to all parts of the body especially colder areas.
57
Where is insulin produced and where is it transported to?
It is secreted by the pancreas and passes to the liver by means of the blood plasma.
58
Why is blood important for defence?
Both platelets and white blood cells are essential for defence.
59
What is the role of platelets?
When there is a wounded area, platelets clump together.
60
What is fibrin?
With the presence of platelets, a network of fibres are formed across the wound.
61
What is the network of fibrin called?
A scab, when this is formed phagocytes fight bacteria.
| Bacteria fight much more quickly than the white blood cells, the dead white blood cells and dead bacteria to form pus.
62
What is the role of white blood cells?
They are part of the immune system and protect the body from foreign invaders which are agents of disease.
63
Why is blood important for homeostasis?
Blood spreads the warmth evenly.
Blood transports substances needed by body, basically glucose and oxygen and immediately removes unwanted substances- CO2
Blood removes excess water from tissue.
64
What are the functions of a circulatory system?
The transport of oxygen from the respiratory system to cells and the removal of carbon dioxide from cells.
Transport of nutrients to cells and wastes from cells to liver or kidney.
Distribution of hormones.
Helps regulate body temperature as blood flow is adjusted.
Prevents blood loss by means of a clotting mechanism.
Enhances the immune system by circulating antibodies and white blood cells.
65
What are blood vessels?
They are tubes that carry fluid to and away from cells.
66
What is the heart?
It serves as a pump to circulate the fluid.
67
There are 3 types of blood vessels. Name them.
Arteries - which carry blood away from the heart.
Veins - carry blood towards the heart.
Capillaries - connect arteries to veins. Arteries form a vein through capillaries.
68
What are arteries characteristics?
They have a thick layer of muscles and elastic fibres, since blood flows at very high pressure within it.
Have a narrow lumen - to maintain high pressure.
They have no valves, they move by pressure itself.
Found deep within the body.
69
What are arterioles capable of?
They are capable of responding to electrical and hormonal signals when changes in the tissue are detected.
70
What are capillaries responsible for?
Capillaries exchange gases, nutrients and wastes between blood and body cells.
71
What is interstitial fluid?
Pressure within the capillaries causes fluid to leak continuously from them into spaces around the capillaries and tissues.
This allows gas, nutrients and waste exchange to occur.
72
How are veins characterised? Also, how do they work?
Their walls are thin and expandable.
The blood pressure in veins is steady and is less than in arteries.
Have a wide lumen.
Have valves - one directional flow, preventing backwards flow.
Contractions of skeletal muscles, squeeze veins to help move blood through them.
Found beneath the skin.
73
What is the lymphatic system?
It removes excess interstitial fluid and molecules that have leaked from capillaries.
Lymph fluid is the interstitial fluid collected by lymph capillaries, it is carried back into the circulatory system in lymph vessels.
74
What is a pulse?
Every time the heart beats, it causes a ripple of pressure to pass down the artery, which can sometimes be felt if the artery is close to the surface.
This occurs during ventricular systole.
75
Name some characteristics of capillaries.
They do not have an elastic fibre or muscle wall - blood has to escape.
Have microscopic lumen, to leak out tissue fluid.
Don't have valves as they do not need them.
Blood moves automatically through them.
Found everywhere in the body.
76
Is the blood within veins deoxygenated or oxygenated?
Deoxygenated, it also contains less food but more carbon dioxide, than the blood in arteries.
77
Arteries always carry oxygenated blood. What is the exception?
The pulmonary artery.
78
Veins always carry deoxygenated blood. There is one exception to this rule, what is it?
Pulmonary vein.
79
What is blood pressure?
The pumping action of the heart produces a pressure which drives blood round the circulatory system.
In medical terms, it means the 2 pressures, as measured in the arteries, when the heart is contracting and relaxing.
80
What can cause the heart rate and pressure to increase?
Emotions, anticipation and stress.
81
What can cause the heart rate and pressure to decrease?
Immersing a face under water.
82
What is the heart rate controlled by?
It is controlled by the brain stem, the medulla oblongata and by the endocrine system by hormones such as adrenaline.
83
When the veins are constricted does this result in a rise of blood pressure?
Yes, and when dilation occurs, it results in the lowering of blood pressure.
84
The heart is divided into 2 sides. What does each side deal with?
The left side of the heart deals with oxygenated blood, while the right deals with deoxygenated blood only.
85
Humans have a double circulatory system. Name them.
Systemic circulation & pulmonary circulation.
86
What is the pulmonary circulation?
This is the circulation through the lungs.
87
Which ventricle has a thicker muscle, the left or the right?
The left side.
88
On average how long does a red blood cell take to go through the whole circulation?
45 seconds.
89
Please describe the properties of oxygenated blood.
It's contains more oxygen, more glucose, less carbons dioxide and less water. It's red in colour.
90
What are the properties of deoxygenated blood.
It contains less oxygen, less glucose, more carbon dioxide, and more water.
It's blueish green in colour.
91
What is the systemic circulation?
The circulation round the rest of the body.
92
What are varicose veins?
Swollen veins found in the legs of elderly people because valves of veins in legs are not working properly.
Can be removed with a minor surgery.
93
What is thrombosis?
It's internal blood blots in vessels leading to the brain.
| A person can die very easily due to this, a person may also end up in paralysis due to this.
94
Where is the heart positioned?
It occupies the central part of the thorax, the lower part is slightly inclined to the left.
95
What is the septum in the heart used for?
To distinguish between the right and left parts of the heart, there is this muscular wall called a septum, it ensures no mixing of blood.
96
What are the valves on the right side of the heart called?
Tricuspid valves.
97
What are the valves on the left side of the heart called?
Bicuspid valves.
98
Why is left ventricle much thicker than the right?
Because it pumps blood to all the organs except the lungs.
| Whereas the right ventricle pumps blood into the lungs only.
99
The atria are separated from the ventricles by means of which valves?
Atrioventricular valves.
100
The ventricles are separated from the arteries by which valves?
Semi-lunar valves.
101
All blood enters the right atrium of the heart through which blood vessel?
The vena cava, it's the main vein in the body.
It brings all the deoxygenated blood from the body tissue.
102
All blood in the left ventricle will exit with what blood vessel?
The aorta.
It's the main artery in the body, and it carries oxygenated blood to the body.
103
Where does blood pass into via the right ventricle?
It passes into the lungs through the pulmonary artery.
| It carries deoxygenated blood.
104
Once blood circulates the lungs where does it go? And through which blood vessel?
It goes to the left atrium via the pulmonary veins.
| It brings oxygenated blood from the lungs into the left atrium.
105
Blood always flows in one ______. Fill in the blank.
Direction.
106
The blood is stopped from flowing backwards by 4 sets of ________. Fill in the blanks.
Valves.
107
The heart itself is made up of muscle. What is this muscle called?
Cardiac muscle. Which is very strong.
108
The heart needs to be supplied with food and oxygen. What surrounds it in order to provide for its needs?
The coronary vein.
109
What happens if too much fat is consumed over time?
The coronary arteries can be blocked with cholesterol. Which could lead to a heart attack.
110
There are 2 'Great Veins' which return all the blood to the right atrium. What are they called?
The superior vena cava - returns deoxygenated blood from the upper parts of the body.
The inferior vena cava - returns deoxygenated blood from the lower parts of the body.
111
What is the average amount of heart beats in a minute?
About 70 times/minute.
This almost doubles when heavy exercise is done.
112
What is the cardiac cycle?
The heart beats with a definite rhythm, it's called the cardiac cycle.
113
The heart beats by the contraction of muscles. How do the atria and ventricles react to this?
They act antagonistic, when one is contracting we say the other is in systole.
114
What does diastole mean?
The phase of the heartbeat when the heart muscle relaxes and allows the chambers to be filled with blood.
115
What occurs during atrial diastole?
Blood from the vena cava enters the right atrium. (Deoxygenated)
Blood from the pulmonary veins enters the left atrium. (Oxygenated)
At first the bicuspid and tricuspid valves are closed, but as the pressure rises it becomes greeter than in the replaced ventricles, mad the valves push open.
116
What occurs during atrial systole?
When atrial diastole ends, the 2 atrial contract simultaneously.
This results in blood being pumped into the ventricles.
117
What does systole mean?
The phase of the heart are when the heart muscle contracts and honors blood from the chambers into the arteries.
118
What occurs during ventricular systole?
Almost immediately after the atrial diastole, the ventricles contract.
When this occurs the pressure in the ventricles rises and close the atrioventricular valves, preventing blood from returning to the atria.
The pressure forces open the semilunar valves of the aorta and pulmonary artery.
(Blood in the aorta goes to all the body except the lungs. Whereas blood in the pulmonary artery goes specifically to the lungs)
119
What occurs during ventricular diastole?
Ventricular systole ends.
The high pressure developed in the aorta and pulmonary artery tends to force some blood back towards the ventricles, which closes the semilunar valves, preventing backwards flow into the heart.
120
One complete heartbeat consists of what?
One systole, and one diastole. Which lasts about 0.8 seconds.
121
Heart cells are myogenic. What does this mean?
They beat out of their own accord, and are not stimulated by any nerve impulses.
122
The contractions of the chambers of the heart are regulated by a cluster of muscles called what?
Cardiac muscle cells which specialise as a pacemaker.
123
Where is the principle cardiac muscle which acts as a pacemaker found? What is it called?
The sinoatrial node, which is found in the wall of the right atrium.
124
How can the heart rate be changed by the pacemaker?
If the pacemaker is stimulated by nerves or hormones.
125
There is another pacemaker found what is it called?
The atrioventricular node.
126
Why is the atrioventricular node slightly delayed to the sinoatrial node?
The electrical impulse is delayed in order to coordinate so that the atria contracts before the ventricles,
127
What are the purkinje fibers?
They are located in the inner ventricular walls of the heart, they are specialised fibres that conduct an electrical impulse/stimulus that enables the heart to contact in a coordinated fashion.
128
What is tissue fluid?
Blood pressure in the capillaries forces part of the plasma out through the capillary walls, this is called tissue fluid.
129
Why is tissue fluid needed?
It helps substances to diffuse into and out of cells. It fills in the narrow spaces between the cells.
130
What's another name for tissue fluid?
Interstitial fluid
131
What does tissue fluid contain?
It contains dissolved food and oxygen and so supplies the cells with their needs.
Receive waste products from the cells.
132
What is coronary heart disease?
It results from blockades of the coronary arteries. There are 3 ways blood flow can be impeded:
Coronary thrombosis that is a blood clot which becomes blocked in a coronary vessel.
Narrowing of the arteries due to the thickening of the arterial wall cause by fat, fibrous tissue and salts being deposited on it.
Spasm - repeated contraction of the muscle in the coronary artery wall
133
What happens if the main artery is blocked? As opposed to a branch being affected?
If the main artery possess coronary heart disease, the result is death, if simply a branch is affected only part of the heart muscle is affected which cause serious chest pains (heart cramps - angina) and temporary incapacitation.
134
What are the main causes for cardiovascular disease?
The main problem is caused by saturated fats that cause a rise in blood cholesterol levels.
Hypertension - a raised blood pressure can considerably increase the chance to develop cardiovascular disease. High blood pressure is also associated with factors such as stress, smoking, alcoholism.
Smoking thickens the artery wall and decreases the a silty to remove blood cloths that may form.
Gender death rates from cardiovascular disease in women are less than halo those for men, women rarely suffer from it before menopause.
Heredity genes and ageing increase the risk of cardiovascular disease.
135
What can decrease the chance of cardiovascular disease?
Physical exercise.
Also polyunsaturated fatty acids found in unsaturated fats are thought to help reduce the cholesterol levels in the blood.
