Organisation ( part 1) Flashcards
(91 cards)
1
Q
Why are scabs formed ?
A
To prevent blood loss and to stop microbes from entering the body
2
Q
How does a scab work ?
A
- platelets arrive at the site of the wound and group together to act like a plug to stop more blood from getting out
- blood clotting protein fibrogen forms a mesh over the wound
- platelets stick to one another and the mesh, completely covering wound
- clot is formed , becomes a scab as it dries out
3
Q
What are capillaries ?
A
Capillaries are small blood vessels which connect arteries to veins. They are the site of exchange between the blood and body tissues.
4
Q
What are the functions of capillaries ?
A
- allow oxygen and nutrients for example ( glucose, vitamins, amino acids, fatty acids) to diffuse from blood to cells
- they also allow waste to diffuse from cells to blood
5
Q
What are the adaptations of capillaries ?
A
- they have very thin walls of only one cell thick which means a short diffusion pathway
- small lumen which increases surface area to volume ratio
6
Q
What is the role of a red blood cell ?
A
Red blood cells transport oxygen around the body
7
Q
What is the role of a white blood cell ?
A
Ingesting pathogens and producing antibodies and antitoxins
8
Q
What is the role of blood plasma ?
A
plasma carries blood cells suspended in it. It also carries many dissolved substances around the body.
9
Q
What is the role of platelets ?
A
platelets are tiny cell fragments involved in blood clotting
10
Q
Explain some adaptations of a red blood cell
A
- contain a protein called haemoglobin to carry the oxygen molecules
- no nucleus, which allows for more haemoglobin
- small and flexible so that they can fit through narrow blood vessels
- biconcave shape to increase surface area for oxygen absorption
11
Q
What substances are carried around the body in blood plasma ?
A
waste carbon dioxide, urea, and insoluble products of digestion
12
Q
what is the difference between white blood cells and red blood cells ?
A
White blood cells are larger than red blood cells and they do have a nucleus
13
Q
What are the four components of blood ?
A
platelets, white blood cells, red blood cells and plasma
14
Q
What do arteries do ?
A
Carry oxygenated blood away from the heart
* except for pulmonary artery
15
Q
what do veins do ?
A
Carry deoxygenated blood towards the heart
* except for pulmonary vein
16
Q
what is the role of valves ?
A
Stop the back flow of blood
17
Q
Blood pressure in capillaries, arteries and veins
A
fairly low
high
low
18
Q
Where is the blood pressure highest ?
A
Near the heart
19
Q
What is the structure of platelets ?
A
Irregular shape, no nucleus and are very small
20
Q
Right hand side of the heart pumps…
A
deoxygenated blood
21
Q
left hand side of the heart pumps…
A
oxygenated blood
22
Q
What is blood pressure ?
A
a measure of the force that your heart uses to pump blood around the body
23
Q
What is the advantage of us having a double circulatory system ?
A
It ensures that we are providing body tissues with fully oxygenated blood rather than a mixture of oxygenated and deoxygenated blood
24
Q
What are the two circuits in the double circulatory system ?
A
Pulmonary circuit and systemic circuit
25
What happens in the pulmonary circuit ?
* Deoxygenated blood pumps from the heart to the lungs, collecting oxygen
* oxygenated blood goes back to the heart
26
What happens in the systemic circuit ?
* Heart pumps oxygenated blood to the organs, where the blood transfers oxygen to body cells
* Deoxygenated blood returns to the heart
27
How does the heart work ?
* blood enters the left and right atrium
* the atria then contract forcing the blood into the ventricles
* the ventricles then contract forcing blood out of the heart
* valves prevent the back flow of blood into the atria when the ventricles contract
28
What are the adaptations of arteries ?
* thick walls containing a lot of muscle and elastic fibres
the muscle makes the arteries strong and able to withstand high BP and the elastic fibres allow them to stretch when blood passes through
* small lumen ( relative to the large vessel) maintains the high blood pressure as blood is transported around the body
29
What are the adaptations of veins ?
* thin walls because the blood in veins has travelled a long distance from the heart so it is at low pressure
* Large lumen and valves make sure that blood is transported efficiently as blood carried by veins moves slower and often against gravity
30
What exactly is the heart ?
A muscular organ that pumps blood around the body
31
What are the two top chambers of the heart called ?
Atria ( left and right atrium)
32
What are the two bottom chambers of the heart called ?
Ventricles
33
What does the vena cava do ?
Pumps deoxygenated blood from around the body back to the heart
34
What is the role of the aorta ?
pumps oxygenated blood away from the heart to the body
35
What does the left ventricle do ?
pumps oxygenated blood to the body through the aorta
36
What does the right ventricle do ?
pumps deoxygenated blood to the lungs through the pulmonary artery
37
What does the pulmonary vein do ?
pumps oxygenated blood from the lungs to the heart
38
What does the pulmonary artery do ?
pumps deoxygenated blood from the heart to the lungs
39
What is the functions of the coronary arteries ?
Provide oxygen to the muscle cells of the heart
| Oxygen is used in respiration to provide energy for contractions
40
What does the septum do ?
It separates the right and left hand side of the heart
41
What does the right atrium do ?
Receives deoxygenated blood from the systemic veins( the superior and inferior vena cava)
42
What does the left atrium do ?
Receives oxygenated blood from the pulmonary veins
43
What is the difference between the biscupid and tricuspid valve ?
* tricuspid valve is found between right atrium and right ventricle
* bicuspid valve is found between left atrium and left ventricle
44
What is atheroma ?
A fatty deposit which forms within the walls of an artery
| * starts off as fatty streaks which can become plaque. The plaques can restrict blood flow
45
What is thrombosis ?
The formation of a blood clot known as a thrombus within a blood vessel
* thrombus may dislodge and block other arteries and veins
* if the blockage is close to junction of coronary arteries and aorta then heart will stop because blood supply is completely cut off.
46
What is an aneurysm ?
A bulge in a blood vessel caused by a weakness in the blood vessel's wall
47
What is myocardial infarction ?
A reduced supply of oxygen to the muscle of the heart, also known as a heart attack.
48
How does breathing work ?
Air enters the mouth and nose, travels through the trachea and into the bronchi. It then enters the lungs and travels through the bronchioles until it reaches the alveoli
* air fills the alveoli causing the lungs to inflate. Diffusion occurs between the capillaries filled with CO 2 and the alveoli which are filled with oxygen. Oxygen diffuses into capillaries and carbon dioxide diffuses into alveoli.
* Oxygen is transported where it is needed via the blood stream and the autonomic nervous system sends a signal to the diaphragm and intercostal muscles to relax. this reduces space in the chest, forcing lungs to compress. CO 2 is exhaled from the body.
49
When does air enter and exit the lungs ?
When there is a difference in pressure
50
What happens in terms of pressure during inhalation ?
Diaphragm contracts which increases the lung volume, causing low pressure inside the lungs. The pressure inside the lungs decreases below that of atmospheric pressure.
Pressure difference causes air to rush into the lungs
51
What happens in terms of pressure during exhalation ?
Diaphragm relaxes, decreasing the lung volume. This increases pressure in the lungs. The pressure in the lungs increases above that of atmospheric pressure
Pressure difference causes air to rush out of lungs
52
when we inhale and exhale what happens to the diaphragm and intercostal muscles ?
When we inhale they contract, increasing lung volume
| When we exhale they relax, decreasing lung volume
53
What happens to rib cage when we inhale and exhale ?
In inhalation, ribcage is pulled upwards and outwards
| In exhalation, rib cage is pulled downwards and inwards
54
Features of protists
* they are eukaryotes
* unicellular organisms
* they can live on inside another organism causing damage
55
Features of viruses
* they are not cellular organisms
* reproduce rapidly in host cells, this can burst cell open
* consist of genetic material and a protein coat
56
Features of bacteria
* they are prokaryotes
* unicellular organisms
* Structure: cell wall and membrane, cytoplasm, genetic material ( in cytoplasm or plasmids)
* produce toxins that harm cells and tissues
* examples of bacteria are lactobacillus, salmonella and staphylococcus
57
Features of fungi
* cell wall of fungi is made from chitin (modified glucose)
* fungi secrete enzymes to digest food and absorb it
* they have thread like structures called hyphae which can produce spores, these enable fungus to be spread easily
58
What are some risk factors of cancer ?
alchohol/ smoking, diet and UV rays/ radiation
59
What is a pathogen and what are the four types ?
A pathogen is a microorganism that causes disease
- bacteria
- viruses
- protists
- fungi
60
What is the respiratory system ?
The organs and other parts of your body involved in breathing ( when you exchange oxygen and carbon dioxide)
61
What is the autonomic nervous system ?
The brain's unconscious control centre for functions like breathing
62
What does the larynx do ?
protects the lower airways, makes breathing easier and helps you speak
63
What are the alveoli ?
The site of gas exchange
64
What is the trachea ?
Air is passed into this tube to get to the bronchi and into the lungs
65
What is the diaphragm ?
A muscle that contracts and relaxes to help get air in and out of lungs
66
What do the intercostal muscles do ?
Protect the lungs
67
What does the nasal cavity do ?
Humidifies and warms the air that we have inhaled, also removes any debris before the air reaches the lower airways.
68
What do the ribs do ?
Protect the vital organs found in the chest and maintains
| space in the chest so lungs can expand and contract during ventilation
69
What is the difference between breathing ( ventilation) and respiration ?
Breathing is the exchange of gases oxygen and carbon dioxide and respiration is the process in which food is broken down in the cells with the help of oxygen to release energy.
* breathing is a part of respiration
70
How is an artificial heart different from a normal heart ?
Artificial hearts aren't living so they need a power source, they are not made of muscle tissue like a normal heart, and they can't change speed to accomodate different energy needs
71
Advantages of artificial hearts
* Artificial heart isn't rejected by the body
| * keeps the patient alive while waiting for a transplant
72
Disadvantages of an artificial heart
* surgery can lead to bleeding and infection
* blood doesn't flow as easily
* can lead to blood clots so blood thinners have to be taken
* parts of the heart can wear out or stop working
* can't change its speed to accomodate different energy needs
73
Symptoms of a faulty valve ( when valve degenerates and stops opening and closing correctly)
- chest pain
- fatigue
- shortness of breath
- irregular heartbeat
74
Advantages and disadvantages of artificial heart valves
+ success rate of artificial heart valve transplant is high
+ prolong person's life
+ fairly durable
_ blood thinners need to be taken to prevent clotting
_ surgery can go seriously wrong
75
What are stents ?
Short wire mesh tubes that can keep a blocked or weakened artery open so blood can continue to flow through
76
Risks and benefits of having a stent
+ decrease chances of a heart attack
+ durable
+ high success rate
_ complications like bleeding and infections
_ arteries don't always stay open
_ blood thinners have to be taken
77
What are adaptations of alveoli ?
* folded shape gives them a large surface area, enables quicker diffusion
* thin walls provide gases with short diffusion distance
* moist walls, gases dissolve in the moisture which helps them pass across the gas exchange surface
* extensive blood supply to ensure that oxygen rich blood is taken away from lungs and CO 2 rich blood is taken to the lungs to be exhaled
78
How can communicable diseases be spread ?
- through contaminated food
- passed by another animal
- through dirty water
- through the air
- by direct physical contact
79
What is a communicable disease ?
Can be transmitted from one person to another by pathogens
80
What is a non communicable disease ?
Cannot be transmitted from one person to another
81
What is an allergy a result of...
It is a result of an error in the immune system, it may react to a harmless substance like pollen because it mistakes it as harmful
82
Why are histamines produces by your cells ?
To help remove the allergens from your body. Histamines cause the symptoms of allergy ie sneezing, watery eyes
83
What is the heart beat controlled by ?
A group of cells called pacemakers which are found in the right atrium
84
What is a placebo ?
A type of fake medical treatment/ drug
85
What are some risk factors of coronary heart disease ?
- smoking ( chemicals in smoke can damage lining of coronary arteries)
- high blood pressure ( puts strain on the heart)
- high cholesterol levels
- high lipoprotein
- lack of exercise ( leads to atheromas)
- diabetes ( may cause lining of blood vessels to thicken, restricting blood flow)
86
What causes coronary heart disease ?
A build up of fatty substances on the walls of the arteries around the heart ( coronary arteries)
87
Why does left ventricle have a thicker wall than the right ventricle ?
The left ventricle has to pump blood at a high pressure so it can reach all the body cells while the right ventricle only has to pump blood to the lungs
88
What is a carcinogen ?
Substance that causes cancer ie chemicals in cigarette smoke
89
What are statins ?
Drugs that reduce amount of LDL cholesterol in the blood
90
What is the difference between a benign and malignant tumour ?
Benign tumour remains in one place, doesn't invade other tissues in the body. Not dangerous
Malignant tumour spreads easily to other parts of the body. They are dangerous
91
Gases travel from...
An area of high pressure to an area of low pressure
