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Flashcards in Topic 1 Deck (119):
1

What processes cause CHD

Athlerosclerosis and blood clots. (due to high blood pressure, toxins and fat deposits)

2

What is a stroke

A stroke is a blood clot in the brain that cuts off blood circulation

3

Why is a circulatory system or a mass transport system needed

For mass flow, to overcome the limitations of diffusion

4

Who uses open cirulatory systems

Insects

5

How does an open circulatory system work

Oxygenated blood is pumped into cavities around vital organs for diffusion. Blood circulates in large cavities

6

Who has closed circulatory systems

Many animals and all vertibrates

7

What does a closed circulatory system contain

Tubes for the blood often vessels, high blood pressure with no cavities for faster transport of blood, either a single or double circulatory system and (in this order) arteries -> arterioles -> capilaries -> venules -> veins.

8

How does a single circulatory system work

Deoxygenated blood is pumped from the heart to the gils, diffusion of substances takes place and the blood oxygenates, the oxygenated blood flows through the body and back to the heart

9

How many atriums and ventricles do single and double circulatory systems have

Double = two of each
Single = one of each

10

How does a double circulatory system work, and what components of the heart does the blood travel through

Deoxygenated blood from the right side of the heart is pumped from the heart to the lungs via Pulmanory artaries. The blood becomes oxygnated in the lungs and returns to the left side of the heart via the pulmanory veins. This oxygenated blood is sent to the body via the aorta, and returns to the right side of the heart via the inferior and superior vena cava.

11

What are the charge properties of water

It is a dipole because it has two equally charged polls. It is also a polar molecule because it has a uneven distribution of charge. Its negative ends are attracted to the positive ends allowing hydrogen bonds to form.

12

What are the solvent properties of water

Many chemicals can dissolve into it due to its dipole nature, this allows vital chemical reactions to take place inside the cytoplasm and allows for the transport of substances.

13

What are the thermal properties of water

Has a high specific heat capacity, therefore a lot of energy is needed to break the hydrogen bonds. This causes water to warm up and cool down slowly.

14

What causes the lub and dub sounds

Lub = atrioventricular valves
Dub = semi-lunar valves

15

What does myogenic mean

It means that something can generate its own impulse

16

What do all vessels contain

Collagen, Elastic fibres, smooth muscle and endothelium

17

What is collagen

Collagen is fibreous proteins which make blood vessels stronger and durable

18

What are the properties of arteries and arterioles

Narrow lumen, thick muscle wall, no valves

19

What are the properties of capillaries

Lumen only allows blood cells through in single file, wall is only one cell thick for higher rates of diffusion. No valves.

20

How does blood flow through the arteries and arterioles

When blood flows into these vessels due to systole, the vessels dilate due to the infulx of blood, this is possible because of the elastic fibres. During diastole pressure is maintained due to the vessels constricting, this also smoothens the flow of blood, this is so there is a steady flow of blood in the smaller arterioles and capillaries.

21

How does the blood flow through the capillaries

The flow of blood is steady in the capillaries for more diffusion of substances, there is also high friction in the capillaries which reduces the rate of the flow. There is one close to every cell in the body.

22

How does the blood flow through the venules and veins

There is a low pressure, and blood flows steadily with no pulses, the flow is assisted by the skeletal muscle pump and breathing. Any backflow of blood is prevented by the semilunar valves.

23

What happens during atrial systole (phase 1)

Blood arrives in the atriums via the inferior and superior vena cavas (right), and the pulmonary veins (left) due to the skeletal muscle pump and breathing. The atriums start to fill with blood and pressure increases forcing some blood through the atrioventricular valves into the ventricles. When systole occurs the atriums contract to force more blood into the ventricles.

24

What happens during ventricular systole (phase 2)

There is a slight delay after atrial systole before ventricular systole takes place. Ventricles contract from the base of the heart upwards increasing pressure on the semilunar valves which open allowing blood into the aorta and the pulmonary arteries. This pressure causes the atrioventricular valves to close preventing the backflow of blood into the atriums.

25

What happens during cardiac diastole (phase 3)

The atriums and ventricles relax, elastic recoil of the heart allow for a decrease in pressure. Due to a higher pressure in the aorta and the pulmonary veins the semilunar valves close. The coronary arteries fill up with blood. Low pressure in the atria helps draw in blood for the next contraction.

26

What is atherosclerosis

It is a disease process that leads to coronary heart disease, creates a fatty deposit in arteries that can block them or increase the chance of a blood clot

27

What happens in the first stage of atherosclerosis

The endothelium layer lining the artery gets damaged due to high blood pressure or toxins in the blood.

28

What happens in the second stage of atherosclerosis

There is an inflammatory response once the inner lining of the artery has been breached. White blood cells leave the blood and enter the artery wall. These cells accumulate

29

What happens in the third stage of atherosclerosis

Calcium salts and fibrous tissue also build up at the site, this results in hard swelling creating a plaque on the inner wall.

30

What is the first thing that happens in the clotting cascade

Platelets and damaged tissue release the protein thromboplastin

31

What is the second thing that happens in the clotting cascade, and what must be present in the blood

Thromboplastin activates the enzyme that catalyses the conversion of the protien prothrombin to the enzyme thrombin. vitamine K and calcium ions must be in the blood.

32

What is the order and names of the proteins and enzymes that are in the clotting cascade

Thromboplastin --> protein
(enzyme activates)
Prothrombin --> protein
(Converts to)
Thrombin --> enzyme
(acts as catalyst for next conversion)
Fibrinogen --> soluble plasma protein
(conversion)
Fibrin --> insoluble protein

33

What is the third thing that happens in the clotting cascade

Thrombin catalyses the conversion of the soluble plasma protein fibrinogen into the insoluble protein fibrin

34

What is the fourth thing that happens in the clotting cascade

Fibrin creates a mesh that traps more platelets and red blood cells

35

What is CHD (coronary heat disease)

Due to narrowing of the coronary arteries, O2 rich blood reaching the cardiac muscle is limited resulting in aerobic respiration and a pain known as angina. If blood supply is cut off (ischaemic) this causes cells to become permanently damaged causing a myocardial infraction

36

What are the symptoms of CHD

• Shortness of breath
• Increases pain, ache or discomfort in chest, left arm or shoulder (women may not get chest pain)
• Similar indigestion symptoms
• Arrhythmia irregular heart beat
Angina

37

What is a stroke

If blood supply is only briefly interrupted = mini stroke (all symptoms of a stroke but for a shorter time) can recover quickly. Blood clot = a full stroke  if cells are starved of O2 it can be fatal

38

What are the symptoms of a stroke

• Numbness
• Dizziness
• Confusion
• Slurred speech
• Blurred vision or one eye vision

39

What is an Aneurysm

A narrowed artery becomes less flexible and blood clot builds most commonly in the aorta. As it grows aorta walls are stretched to 6-7cm in diameter and rupture. A bulge can be felt

40

What are the symptoms of an aneurysm

Bulge in chest

41

What are the risk factors of CVD

• Age --> old have higher risk
• Sex --> males have higher risk
• Heredity (genetic inheritance)
• Physical environment --> drugs, diet and exercise
• Social environment --> what people around you do and tell you to do
• Life style and behaviour --> drugs, diet and exercise
• high bp
• obesity
• high blood cholesterol
• smoking
• inactivity

42

Why do people over estimate and underestimate

Because it is either involuntary, not natural, unfamiliar, dreaded, unfair or has a very small risk

43

Why are null hypothesis and control variables used

To find if the causation and correlation is linked

44

What types of studies can be used

Cohort and case control studies

45

What is a cohort study

• Follow a large group of people and looks to see who develops the disease and who doesn’t, they find a causation and correlation.
• Prospective --> no one starts with the disease
OR
• Follow two groups one exposed to possible risk factor, the other is not exposed to the possible risk factor. This is to determine the causation and correlation.

46

What is a case control study

• People with the disease are compared with people who don’t
• Info on key factors are collected

47

Give an example of cohort study

In 1948 the Framingham heart study, the aim was to identify factors that contribute to the disease
• 5209 men + women ages 30-62 with no symptoms
• 2nd generation joined the study to the 3rd generation joined to this day
Every two years they provide medical history, physical examination and answer questions about lifestyle

AND
World health organisation
• 10 million people 25-64, in 21 countries for 10 years
• Finished in 1990s

48

Give an example of a control study

Global case-control study called INTERHEART this study Screened patients who got a heart attack from 262 hospitals in 52 countries, got 15152 causes and 14820 controls

49

What are the main features of a good study

Clear aim, Representative sample, valid and reliable results, sample size and controlling variables.

50

What is a calorie

A calorie is the quantity of heat energy required to raise 1cm³ of H2O by 1°C or K, C=calorie

1000c = 1kc 1C = 4.18J, 1kc=0.00418J

51

Where does energy come from

Carbohydrates, lipids and protein

52

What reverses a condensation reaction and what is required

Hydrolysis, water is needed

53

What are the three types of carbohydrates

Monosaccharides, Disaccharides and Polysaccharides

54

Name three types of Monosaccharides, and what typess of sugar they are.

Glucose, Galactose and Fructose. They are 6 carbon hexose sugars and monomers

55

Name three Disaccharides

Maltose, Sucrose and Lactose

56

Name three Polysaccharides

Starch, Glycogen and Cellulose

57

What are the main things about glucose

It is the main sugar in cell membranes, makes starch and glycogen.

58

What are the key things about Galactose

Its the main sugar in Lactose

59

What are the key things about fructose

Naturally in fruit and some vedge, sweetness attracts animals and is absorbed rapidly by the blood

60

What are the key things about Sucrose

Is made of a glucose + fructose, is the usual form of sugar for transport in plants

61

What are the key things about Maltose

Made of two glucose molecules, produced when amylase breaks down and can be found in germinating seeds

62

What are they key things about Lactose

Made of glucose + galactose and is the main sugar in milk

63

What are monosaccharides

Single sugar units that have 3-7 carbon atoms and are rapidly absorbed by the blood

64

What are Disaccharides

Made from two single sugar units (monosaccarides), forms 1-4 glycosidic bonds and has to be digested into monosaccarides for absorption

65

What are Polysaccharides

Is a long chain of monomers = polymer, all joined together with 1-4 glyocidic bonds and are not very soluble

66

What are the key things about starch

Main storage molecule in cells, it is a compact molecule with low solubility in water and thus does not extract water into the cell via osmosis

67

What are the two types of Polysaccharides that make up a starch molecule

Made of Amylose (20-30%, straight helix, chains 200-5000 glucose with 1,4 glycosidic bonds) and Amylopectin (70-80%, same as amylose but has side branches with 1,6 glycosidic bonds) which is more soluble in water

68

What are the key things about Glycogen

• Used by bacteria, fungi and animals instead (or in combination with) of starch as a storage molecule
• Has numerous side branches
• Can be rapidly hydrolysed
• Humans store it in the liver and muscles

69

What are the key things about Cellulose

• Is a dietary fibre
• Non-starch polysaccharide
• 10000 glucose joined together to form a straight chain with 1,4 glycosidic bonds
• Indigestible to humans but helps movement in the digestive tract

70

What are some key things about fats

• Supply over double the energy as carbs (37Jk g⁻¹)
• Insoluble in water but soluble in organic solvents such as ethanol
• Provide energy and essential fatty acids that the body cannot produce

71

What is the general structure of a lipid

Most of them are triglycerides  which are made from three fatty acids and one glycerol connected by an ester bond which is formed in a condensation reaction (one for each fatty acid)

72

What are saturated fats

• If the fatty acid chain is a lipid containing the max amount of hydrogens it is saturated
• No carbon to carbon=straight chain
• Pack closely together and have strong intermolecular bonds

73

What are unsaturated fats

• Are not straight, have double carbon – carbon bonds cause kinks in the chain
• Monounsaturated has one double bond in each chain
• Polyunsaturated has a large number of double bonds
• Both can’t pack closely together and are liquid at room temperature
• Can be hydrated and made saturated = hydronated or trans fats

74

What is cholesterol

• Short molecule essential for good health
• Vital in cell membranes
• Makes some sex hormones such as progesterone and testosterone
• Forms bile salts for digestion
• Obtained from saturated fats

75

What is DRVs

Dietary reference values
• Essential average requirements
• Lower reference nutrient intake (the least amount of nutrients required)
• Higher reference nutrient intake (the most nutrients required)

76

What is BMR

Basel metabolic rate
• Is the energy required for essential body processes
• Higher in, males, fat, younger and more active people

77

What is BMI and how is it measured

Body mass index
• A method for classifying body weight
• Kg/m²=BMI

78

What is waist to hip ratio and how is it measuresd

• Better measure than BMI, due to its better correlation with heart attacks
• Waist circumference (narrow point between hip bone and rib cage)/hip circumference (widest point around the glutes)
• Men should be over 0.9
• Women should be over 0.85

79

What are the consequences of obesity

• Increases the risk CHD, stokes and type 2 diabetes
• Elevated bp, lipid levels = CVD

80

What is type 2 diabetes

Can’t produce sufficient insulin or body fats (type 1 is unable to take in insulin). Insulin is a hormone that regulated blood glucose levels, it is produced by the pancreas, and causes cells to absorb glucose.

81

What are lipoproteins

Insoluble cholesterol combined with proteins to make it soluble

82

What are the two main types of lipoprotein, and which are good or bad

LDL (bad) and HDL (good)

83

What are LDLs

• Triglycerides + cholesterol + protein
• Circulates the blood stream, binds to cell receptors to be absorbed
• Excess can overload the cells receptors and cause deposits on the artery wall as atheroma’s (part of atherosclerosis)

84

What are the HDLs

• More protein less cholesterol (semi triglyceride) = more dense
• Transports cholesterol from tissues to liver and breaks down
• Causes cholesterol levels to decrease and remove plaques

85

What is the difference between saturated and unsaturated

• Saturated = more LDL and HDL but significantly more LDL
• Polyunsaturated fat = decrease in LDL and HDL but significantly more LDL is decreased

86

What why is smoking bad

• CHD is 60% higher in smokers
• CO binds to haemoglobin instead of O2 meaning less gets to the cells and increases the risk of a myocardial infraction (aerobic respiration)
• Nicotine produces adrenaline which increases heart rate and vasconstricts arteries and arterioles which increases blood pressure
• Chemicals damage the lining of the arteries  atherosclerosis
• Reduction of HDL cholesterol

87

Why is inactivity bad

• Moderate exercise prevents high bp and can lower resting bp
• Help maintain a healthy weight
• Increase HDL but has no effect on LDL
• Reduces risk of type 2 diabetes
• More likely to survive a myocardial infraction

88

What negatives to inheriting

Can be more likely to develop a disease, can get defective alleles.

89

What is sickle cell

Is inherited, and causes red some red blood cells to be a sickle or crescent shape, which can restrict blood vessels and also makes them unable to carry O2

90

Can gene disorders increase the chance of CHD

Yes

91

What is a Apolipoprotein gene cluster

• This is an example of where several genes can affect the likelihood of CVD
• This gene cluster has been linked with Alzheimer’s
• Apolipoprotein is a component for lipoproteins

92

What are the three types of Apolipoprotein

APOA
APOB
APOE

93

What is APOA

• major protein in HDLs and helps with removal
• mutations can cause a reduction of removal which will increases the chance of CVD

94

What is APOB

• Major protein in LDL
• Mutations result in higher LDL levels in blood = higher risk of CVD

95

What is APOE

• Major component in HDLs and VLDL (very-low density lipoprotein) which both remove excess cholesterol to the liver
• All are ok except for APOE4 which slows down the removal of cholesterol = increase the risk of CVD

96

Why is CHD multi-factorial

because there are multiple factors such as genes that effect it

97

How can salt contribute to CVD

causes kidneys to retain water = high fluid levels in blood = higher bp

98

How can stress contribute to CVD

release of adrenaline = arteries and arterioles to vasoconstrict = higher bp

99

How can alcohol contribute to CVD

• Raised bp
• Contributes to obesity
• Irregular heart beat (Arrhythmia)
• Damage liver = impaired ability to remove carbs, proteins and lipids from the blood, plus detoxification (removal of toxic substances)
• Alcohol is converted into ethanol = more VLDL = higher chance of plaque formation.

100

How can coffee contribute to CVD

It may or may not contribute

101

How to reduce risk of CVD

• No smoking
• Bp bellow 140/85 mmHg
• Low cholesterol
• Normal BMI and waist to hip ratio
• Regular physical exercise
• Moderate to no alcohol
• More polyunsaturated fats

102

How to control blood pressure

Change lifestyle, take drugs

103

What drugs are prescribed to people with high blood pressure

ACE inhibitors, Calcium channel blockers and Diuretics

104

What do ACE inhibitors do

• Effective antihypertensive drug  reduces the synthesis of angiotensin 2, which causes the vasoconstriction in vessels
• The drug prevents the production of angiotensin 2 from the inactive angiotensin 1

105

What are the side effects of ACE inhibitors

• Dry cough
• Dizziness
• Arrhythmia
• Reduction in kidney function

106

What do calcium channel blockers do

• Antihypertensive drug
• Blocks Ca channels to muscles so vessels cant contract and constrict

107

What do diuretics do

• Increases the volume of urine produced by the kidneys and rid the body of excess fluids and salt
• Decreases the blood plasma volume and cardiac output

108

What are the side effects of calcium channel blockers

• Headaches
• Dizziness
• Swollen ankles
• Arrhythmia
• Red face

109

What are the side effects of diuretics

• Dizziness
• Nausea
• Muscle cramps

110

How can humans decrease there blood cholesterol

Diet and Drugs double D!

111

What drugs can be used to reduce blood cholesterol

Statins or anticoagulant and platelet inhibitory

112

What are the anticoagulant and platelet inhibitory drugs

Aspirin, Clopidogrel and Warfarin

113

What am i doing with my life

hitting lifts killing siths

114

What are the side effects of using statins

• Tiredness
• Disturbed sleep
• Feeling sick to actually vomiting
• Diarrhoea
• Headache
• Muscle weakness
• Cause of cancers such as gastrointestinal and respiratory

115

What elements of dieting can help reduce cholesterol levels

• Energy balance
• Reduced saturated fat
• More polyunsaturated fats
• Reduced cholesterol
• Reduced salt
• More non-starch polysaccharides e.g pectins
• More oily fish, fruit and vedge

116

What does aspirin and Clopidogrel do

reduces the stickiness of the platelets = reduce likely hood of clots (however some people are allergic to aspirin)

117

What does warfarin do

Interferes with the production of vitamin K = effects the conditions needed for a clot to form

118

What are the side effects of using anticoagulant and platelet inhibitory drugs

• Bleeding in the gastrointestinal tract, warfarin has the lowest probability of this, it is higher with aspirin and especially when aspirin is combined with Clopidogrel

119

What is the platelet plug

Platelets turn into spheres with long projections from flat discs, they stick to exposed collagen