Topic 1 Circulatory Systems Flashcards
1
Q
What percentage of a cell’s contents is made up of water?
A
About 80%
Water is crucial for various biological functions within cells.
2
Q
What is one key function of water in biological systems?
A
Water is a solvent
Most biological reactions occur in solution, making water essential.
3
Q
How does water facilitate the transport of substances?
A
Water transports substances by dissolving them
Substances like glucose and oxygen can be transported easily when dissolved in water.
4
Q
What is the chemical structure of a water molecule?
A
One atom of oxygen joined to two atoms of hydrogen
The structure involves shared electrons between the atoms.
5
Q
What charge does the oxygen atom in a water molecule carry?
A
Slightly negative charge
This is due to the unshared negative electrons on the oxygen atom.
6
Q
What charge do the hydrogen atoms in a water molecule carry?
A
Slightly positive charge
This occurs because the shared electrons are pulled toward the oxygen atom.
7
Q
What type of molecule is water considered due to its charge distribution?
A
Dipolar molecule
Water has a partial negative charge on one side and a partial positive charge on the other.
8
Q
What is hydrogen bonding in relation to water?
A
Attraction between slightly negatively charged oxygen and slightly positively charged hydrogen
Hydrogen bonds give water its unique properties.
9
Q
How does water’s dipolar nature contribute to its cohesiveness?
A
It allows water molecules to stick together
Cohesion helps water to flow and transport substances effectively.
10
Q
What is cohesion?
A
Attraction between molecules of the same type
In water, this refers to the attraction between water molecules.
11
Q
What type of substances does water dissolve effectively?
A
Ionic substances
This includes substances like salt, which consists of positive and negative ions.
12
Q
Why do multicellular organisms require mass transport systems?
A
To deliver raw materials and remove waste
Diffusion alone is insufficient due to the larger distances in multicellular organisms.
13
Q
What is the role of the circulatory system in mammals?
A
It pumps blood around the body
The system transports nutrients and oxygen to cells while removing metabolic waste.
14
Q
Fill in the blank: Water’s dipole nature makes it useful as a _______ in living organisms.
A
solvent
This property allows important ions and substances to dissolve in biological fluids.
15
Q
True or False: In single-celled organisms, raw materials can diffuse directly into the cell.
A
True
The short distances allow for quick diffusion.
16
Q
What do individual cells in tissues and organs obtain from the blood?
A
Nutrients and oxygen
They also dispose of metabolic waste into the blood.
17
Q
Explain how the structure of water enables it to transport substances.
A
Water’s dipolar nature allows it to dissolve ionic substances and facilitates cohesion, aiding transport
The combination of these properties makes water an effective transport medium.
18
Q
What are the two main muscular pumps of the heart?
A
Left ventricle and right ventricle
The heart consists of two muscular pumps that work together to circulate blood.
19
Q
What is the main function of the left ventricle?
A
To pump blood all the way round the body
The left ventricle has thicker walls to contract powerfully for this purpose.
20
Q
What is the primary role of the right ventricle?
A
To pump blood to the lungs
The right side of the heart only needs to get blood to the lungs, which are nearby.
21
Q
Why do the ventricles have thicker walls than the atria?
A
Because they have to push blood out of the heart
Atria only need to push blood a short distance into the ventricles.
22
Q
What are atrioventricular (AV) valves responsible for?
A
Linking the atria to the ventricles and preventing backflow into the atria
Cords attach the AV valves to the ventricles to ensure they do not get forced up into the atria.
23
Q
What do semi-lunar (SL) valves do?
A
Link the ventricles to the pulmonary artery and aorta, preventing backflow into the heart
These valves operate after the ventricles contract.
24
Q
How do valves in the heart function?
A
They open or close based on the relative pressure of the heart chambers
Higher pressure behind a valve forces it open, while higher pressure in front forces it shut.
25
What is the function of arteries?
Carry blood from the heart to the rest of the body
## Footnote
Arteries are thick-walled and muscular to withstand high pressure.
26
What is the structure of veins?
Wider than arteries, with thin walls and valves to prevent backflow
## Footnote
Veins carry blood back to the heart under lower pressure.
27
What are capillaries and their primary function?
The smallest blood vessels where metabolic exchange occurs
## Footnote
Capillary walls are only one cell thick to facilitate diffusion.
28
Fill in the blank: The inner lining of arteries is called _______.
endothelium
## Footnote
The endothelium is folded to allow expansion under high pressure.
29
What is the significance of capillary beds?
Increase the surface area for exchange
## Footnote
This structure helps in the efficient exchange of substances like glucose and oxygen.
30
True or False: The left ventricle has thinner walls than the right ventricle.
False
## Footnote
The left ventricle has thicker walls due to its role in pumping blood throughout the body.
31
What precautions should be taken during a heart dissection?
Cut away from yourself and disinfect work surfaces
## Footnote
Safety is paramount to avoid injury and contamination.
32
Describe the structure of an artery.
Thick muscular walls with elastic tissue and folded endothelium
## Footnote
This structure helps arteries cope with high pressure from the heartbeat.
33
What are the three stages of the cardiac cycle?
* Ventricular diastole, atrial systole
* Ventricular systole, atrial diastole
* Cardiac diastole
## Footnote
These stages describe the sequence of events in the heart during each cycle of pumping blood.
34
What occurs during ventricular diastole, atrial systole?
The atria contract, decreasing the volume of the chambers and increasing the pressure inside the chambers, pushing blood into the ventricles.
## Footnote
This stage involves the opening of AV valves and slight increase in ventricular pressure.
35
What happens during ventricular systole, atrial diastole?
The ventricles contract, decreasing their volume and increasing their pressure, forcing the AV valves shut and opening the SL valves to eject blood into the aorta and pulmonary artery.
## Footnote
This prevents back-flow and ensures blood is pushed out of the heart.
36
What is the role of the AV valves during the cardiac cycle?
The AV valves open to allow blood flow from the atria to the ventricles and close to prevent back-flow during ventricular contraction.
## Footnote
AV stands for atrioventricular valves.
37
What occurs during cardiac diastole?
The ventricles and atria relax, SL valves close to prevent back-flow, and blood fills the atria from the vena cava and pulmonary vein.
## Footnote
This relaxation phase prepares the heart for the next cycle.
38
True or False: The pressure in the ventricles is always higher than in the atria during the cardiac cycle.
False.
## Footnote
The pressure in the ventricles is lower than in the atria during the relaxation phase (cardiac diastole) which allows the AV valves to open.
39
Fill in the blank: Blood starts flowing into the aorta when the ventricles are _______.
[contracting]
## Footnote
This occurs during ventricular systole when the pressure in the ventricles exceeds that in the aorta.
40
What causes the SL valves to close during the cardiac cycle?
Higher pressure in the pulmonary artery and aorta compared to the ventricles.
## Footnote
This prevents back-flow of blood into the ventricles.
41
What is the heart rate of a person if one cardiac cycle takes 0.54 seconds?
110 beats per minute
## Footnote
Calculated by dividing 60 seconds by 0.54 seconds per cycle.
42
During which phase do the AV valves open?
During cardiac diastole when the pressure in the atria exceeds that in the ventricles.
## Footnote
This allows passive filling of the ventricles.
43
What happens to the pressure in the ventricles during ventricular systole?
The pressure increases as the ventricles contract.
## Footnote
This increase in pressure is necessary to eject blood into the arteries.
44
Between what times are the AV valves shut?
Between the times when the ventricles are contracting and the pressure in the ventricles is higher than in the atria.
## Footnote
This typically occurs during ventricular systole.
45
Describe what happens to the ventricles and atria during cardiac diastole.
Both ventricles and atria relax, filling with blood as the pressure in the atria rises above that in the ventricles.
## Footnote
This phase prepares the heart for the next contraction.
46
What is a microscope slide?
A strip of clear glass or plastic used to hold specimens for viewing under a microscope.
47
What are the two main ways of preparing a microscope slide?
* Dry mount
* Wet mount
48
Describe the process of creating a wet mount.
1. Pipette a small drop of water onto the slide.
2. Use tweezers to place the specimen on top of the water drop.
3. Tilt and lower a cover slip onto the specimen to avoid air bubbles.
4. Optionally, add a stain by placing a drop next to the cover slip and using a paper towel to draw it under.
49
What is a dry mount?
A method where the specimen is placed directly on the slide with a cover slip on top, without adding water or stain.
50
What is the first step in using a light microscope?
Clip the slide containing the specimen onto the stage.
51
Which objective lens should be selected first when using a light microscope?
The lowest-powered objective lens.
52
What is the purpose of the coarse adjustment knob?
To move the stage up or down to bring the specimen into focus.
53
How do you calculate the heart rate of Daphnia?
Count the number of heartbeats in 20 seconds and multiply by three to get beats per minute.
54
What is the effect of caffeine concentration on Daphnia heart rate?
Heart rate increases as caffeine concentration increases.
55
What should be done to ensure valid results when investigating the effect of caffeine on heart rate?
Keep other factors constant, such as temperature and type of Daphnia.
56
What ethical concerns are associated with using invertebrates in experiments?
* Lack of consent from the animals
* Potential for causing distress or suffering
* The debate over whether it's acceptable to experiment on simpler organisms compared to vertebrates.
57
True or False: Daphnia are considered vertebrates.
False
58
Fill in the blank: A good way to visualize the effect of caffeine concentration on heart rate is to draw a _______.
[graph]
59
List the steps to investigate the effect of caffeine on Daphnia heart rate.
* Prepare caffeine solutions of different concentrations
* Transfer Daphnia to a cavity slide
* Add caffeine solution and wait for absorption
* Observe under a microscope and count heartbeats
* Repeat with different concentrations and a control solution.
60
What is the purpose of the fine adjustment knob?
To refine the focus of the image until it is clear.
61
What is a control solution in an experiment?
A solution that has no caffeine, used for comparison against other concentrations.
62
What is the relationship between caffeine concentration and heart rate as shown in the experiment?
A positive correlation exists; as caffeine concentration increases, heart rate also increases.
63
What is the first step in preparing a microscope slide?
Put the specimen on a slide.
64
What are the two main ways of preparing a microscope slide?
* Dry mount
* Wet mount
65
What is a wet mount used for?
Looking at tiny organisms that live in water.
66
How do you create a wet mount slide?
Pipette a small drop of water onto the slide, place the specimen on top, and cover with a cover slip.
67
What should you avoid when placing the cover slip on a wet mount?
Getting air bubbles under the slip.
68
What is the purpose of adding a stain to a wet mount?
To enhance visibility of the specimen.
69
How is a dry mount slide prepared?
Place the specimen directly on the slide with a cover slip on top, without adding water or stain.
70
What is the first step when using a light microscope?
Clip the slide containing the specimen onto the stage.
71
What should you select before viewing a specimen under a microscope?
The lowest-powered objective lens.
72
What is the function of the coarse adjustment knob?
To move the stage up or down to focus the image.
73
What should you do if you need greater magnification after focusing?
Swap to a higher-powered objective lens and refocus.
74
How do you measure the heart rate of Daphnia?
Count the number of heartbeats in 20 seconds and multiply by three.
75
What should be kept constant when investigating the effect of caffeine on heart rate?
* Temperature
* Volume of caffeine solution
76
What does a positive correlation in the results of the Daphnia experiment indicate?
As caffeine concentration increases, heart rate also increases.
77
What are some ethical considerations when experimenting on invertebrates?
* They cannot give consent
* They may be subjected to painful procedures
78
Why might some people find it more acceptable to experiment on invertebrates than vertebrates?
Invertebrates are considered simpler organisms with less sophisticated nervous systems.
79
Fill in the blank: The average heart rate is calculated by taking the average of _______ readings at each caffeine concentration.
10
80
True or False: It is ethical to cause distress or suffering to any living organism during experiments.
False
81
What is cardiovascular disease associated with?
The heart and blood vessels.
82
What is the first step in the formation of an atheroma?
Damage to the endothelium.
83
What are the components that clump together to form fatty streaks under the endothelium?
* White blood cells
* Lipids (fats)
* Connective tissue
84
What is the fibrous plaque formed during atheroma development called?
Atheroma.
85
What condition results from the hardening of arteries caused by atheromas?
Atherosclerosis.
86
What triggers thrombosis in arteries?
Rupture of an atheroma.
87
What can occur as a result of a blood clot formed from thrombosis?
* Complete blockage of the artery
* Dislodging and blocking a blood vessel elsewhere
88
What are three forms of cardiovascular disease caused by blood clots?
* Heart attack
* Stroke
* Deep vein thrombosis
89
Fill in the blank: Thrombosis is used by the body to prevent _______ when a blood vessel is damaged.
blood loss
90
What protein is released from a damaged blood vessel to initiate blood clot formation?
Thromboplastin.
91
What does thrombin catalyze the conversion of?
Fibrinogen to fibrin.
92
What forms the mesh that traps platelets and red blood cells to create a blood clot?
Fibrin fibres.
93
What is a myocardial infarction more commonly known as?
Heart attack.
94
What happens when a coronary artery becomes completely blocked by a blood clot?
An area of the heart muscle is cut off from its blood supply.
95
What is coronary heart disease (CHD)?
When the coronary arteries have many atheromas, restricting blood flow to the heart.
96
What is a stroke?
A rapid loss of brain function due to a disruption in blood supply to the brain.
97
What is deep vein thrombosis (DVT)?
Formation of a blood clot in a vein deep inside the body, usually in leg veins.
98
What factors can increase the risk of DVT?
* Prolonged inactivity
* Age
99
True or False: A heart attack can cause damage and death of the heart muscle.
True.
100
What lifestyle factor increases the risk of cardiovascular disease due to high cholesterol levels?
A diet high in saturated fat
## Footnote
A high saturated fat diet increases atheroma formation, which can lead to blood clots and cardiovascular events.
101
How does a diet high in salt affect cardiovascular disease risk?
It increases the risk of high blood pressure
## Footnote
High blood pressure is a significant risk factor for cardiovascular disease.
102
What is the effect of high blood pressure on artery walls?
It increases the risk of damage to the artery walls
## Footnote
Damaged artery walls can lead to atheroma formation and cardiovascular disease.
103
What harmful substance in cigarette smoke reduces oxygen transport in the blood?
Carbon monoxide
## Footnote
Carbon monoxide combines with hemoglobin, reducing oxygen delivery to tissues.
104
What effect does nicotine have on blood platelets?
It makes platelets sticky
## Footnote
Sticky platelets increase the chance of blood clots forming, raising cardiovascular disease risk.
105
How does smoking affect antioxidants in the blood?
It decreases the amount of antioxidants
## Footnote
Fewer antioxidants lead to increased cell damage in artery walls, promoting atheroma formation.
106
What is a consequence of physical inactivity regarding cardiovascular disease?
It increases blood pressure
## Footnote
Higher blood pressure is a risk factor for cardiovascular disease.
107
What genetic factor can increase the risk of cardiovascular disease?
Inheritance of particular alleles
## Footnote
Certain alleles may lead to high blood pressure or cholesterol levels.
108
How does age affect the risk of cardiovascular disease?
The risk increases with age
## Footnote
Plaque can build up slowly over time, leading to cardiovascular disease.
109
Which gender is more likely to suffer from cardiovascular disease?
Men
## Footnote
Men are three times more likely to develop CVD than pre-menopausal women.
110
What is the definition of risk in the context of cardiovascular disease?
The chance of something unfavourable happening
## Footnote
For example, smoking increases the chance of developing cardiovascular disease.
111
True or False: The statistical chance of dying from cardiovascular disease is lower for smokers than non-smokers.
False
## Footnote
Smokers have a 60% higher risk of dying from cardiovascular disease.
112
What can lead people to overestimate the risk of developing cardiovascular disease?
Constant exposure to health-related information
## Footnote
Media articles can create heightened awareness and fear regarding health risks.
113
What could cause someone to underestimate their risk of cardiovascular disease?
Lack of information
## Footnote
Being unaware of the contributing factors to diseases like CVD can lead to underestimation.
114
Fill in the blank: A _______ is a fatty deposit that can lead to cardiovascular disease.
atheroma
## Footnote
Atheromas can cause thrombosis, increasing the risk of cardiovascular events.
115
What is the role of fibrin in the blood clotting process?
Fibrin forms a mesh that stabilizes the blood clot
## Footnote
It is essential for the final stage of blood clot formation.
116
How does excessive alcohol consumption affect cardiovascular disease risk?
It increases blood pressure
## Footnote
High blood pressure is a major risk factor for cardiovascular disease.
117
What is the difference between correlation and causation?
Correlation does not prove that a change in one causes a change in the other.
## Footnote
This distinction is crucial when interpreting data on risk factors.
118
What should be evaluated when assessing the design of a study?
* Sample size
* Selection of sample
* Control of variables
* Data collection methods
* Presence of controls
* Repetition by other scientists
## Footnote
Each of these factors affects the reliability and validity of study results.
119
How does controlling variables improve a study's validity?
Controlling variables ensures that only the intended factor is being tested.
## Footnote
This reduces confounding factors that could skew results.
120
What is a potential drawback of using questionnaires for data collection?
Questionnaires can introduce bias, which decreases the reliability of the results.
## Footnote
Bias can occur if respondents do not answer truthfully or consistently.
121
Fill in the blank: The more reliable the results, the greater the number of _______.
people used in a study.
122
Why is it important to look at the data collection method when evaluating study design?
It affects the reliability of the results; less bias leads to more reliable data.
## Footnote
Data collection methods can significantly influence the outcome and interpretation of a study.
123
What are two reasons why a study involving 168,000 people shows strong evidence for a link between waist measurement and cardiovascular disease?
* Large sample size increases reliability
* Independent association shows a direct link
## Footnote
The strength of the correlation is enhanced by the large and diverse sample.
124
What are two ways to increase the reliability of study results?
* Increase sample size
* Control for more variables
## Footnote
These actions help to ensure that the findings are more generalizable and valid.
125
What is the primary goal of antihypertensives in treating CVD?
Reduce high blood pressure
## Footnote
Antihypertensives can include beta blockers, diuretics, and vasodilators.
126
What are the benefits of using antihypertensives?
Different types work in combination to lower blood pressure and allow for home monitoring
## Footnote
This helps patients track the effectiveness of their treatment.
127
What are some side effects of antihypertensives?
Palpitations, abnormal heart rhythms, fainting, headaches, drowsiness, allergic reactions, and depression
128
How do statins help in the treatment of CVD?
Reduce the amount of 'bad' LDL cholesterol in the blood
## Footnote
This lowers the risk of atheroma formation.
129
What are the risks associated with statins?
Muscle and joint pain, digestive problems, increased risk of diabetes, nosebleeds, headaches, and nausea
130
What is the primary function of anticoagulants in CVD treatment?
Reduce the formation of blood clots
131
What are the benefits of using anticoagulants?
Prevent existing blood clots from growing and prevent new clots from forming
132
What are the risks of using anticoagulants?
Excessive bleeding, allergic reactions, osteoporosis, tissue swelling, and potential harm to a fetus during pregnancy
133
What do platelet inhibitory drugs do?
Prevent platelets from clumping together to form blood clots
134
What are the benefits of platelet inhibitory drugs?
Can treat people with existing blood clots or CVD
135
What are the risks associated with platelet inhibitory drugs?
Rashes, diarrhea, nausea, liver function problems, and excessive bleeding
136
True or False: Anticoagulants can eliminate existing blood clots.
False
## Footnote
Anticoagulants can only prevent clots from growing or new clots from forming.
137
Fill in the blank: Statins reduce the risk of developing CVD by lowering _______.
blood cholesterol levels
138
What condition can antihypertensives help reduce the risk of developing?
Coronary heart disease (CHD)
139
Name one disadvantage of taking antihypertensives.
Potential for side effects like fainting or headaches
140
Name a medication type that can be prescribed for high blood pressure.
Antihypertensives
141
What should patients be aware of regarding the effectiveness of CVD medications?
They do not cure the problem; they prevent worsening of conditions
142
What is an energy budget?
The amount of energy taken in by an organism (in food) and the amount of energy used up by an organism.
143
What happens when there is an energy imbalance in an organism's energy budget?
It will affect the person's weight.
144
What causes weight gain in relation to energy intake and output?
If energy intake is higher than energy output, the excess energy will be turned into fat reserves.
145
Fill in the blank: If a person consumes food containing 4000 Calories a day and burns 3000 Calories a day, they will have an excess of _______ Calories per day.
1000
146
What can sustained excess energy intake lead to?
Obesity
147
What causes weight loss in relation to energy intake and output?
If energy intake is lower than energy output, the body will turn some fat reserves into energy.
148
Fill in the blank: If a person consumes food containing 2500 Calories a day but burns 3000 Calories a day, they will have an energy deficit of _______ Calories per day.
500
149
What can sustained energy deficit lead to?
Underweight
150
What chemical is used to measure the amount of Vitamin C in food?
DCPIP
151
What is the first step in measuring vitamin C concentration using DCPIP?
Make up several vitamin C solutions of different, known concentrations.
152
What should be kept constant during the experiment to measure vitamin C concentration?
All other variables, e.g. temperature.
153
What is the purpose of creating a calibration curve in the vitamin C experiment?
To find the concentration of vitamin C in an unknown solution.
154
What is the recommended daily intake of Calories for women?
2000
155
What is the recommended daily intake of Calories for men?
2500
156
What formula is used to calculate a person's energy budget?
Energy input - energy output = energy budget
157
What did Ranjit’s energy budget calculation reveal?
His energy budget is balanced.
158
True or False: Eating beans can increase the amount of Calories used for bodily functions.
True
159
What short-term effect does a balanced energy budget have on a person's weight?
No significant change in weight.
160
What long-term effect can an energy budget imbalance have?
Weight gain or loss depending on the imbalance.
161
What are carbohydrates primarily composed of?
Long chains of monosaccharides
## Footnote
Monosaccharides are the small basic molecular units of carbohydrates.
162
What is a monosaccharide?
A single sugar unit
## Footnote
Examples include glucose and fructose.
163
What is the structure of glucose?
Six carbon atoms in each molecule
## Footnote
Glucose is the primary energy source for animals and plants.
164
What are the two types of glucose you need to learn about?
Alpha (α) and beta (β)
## Footnote
Only alpha-glucose is needed for this section.
165
What type of bond joins monosaccharides together?
Glycosidic bonds
## Footnote
Formed during a condensation reaction where water is released.
166
What happens during a hydrolysis reaction?
A molecule of water reacts with a glycosidic bond, breaking it apart
## Footnote
This is the reverse of a condensation reaction.
167
What is a disaccharide?
A molecule formed by two monosaccharides
## Footnote
Examples include maltose and sucrose.
168
What are the two polysaccharides you need to learn about?
Starch and glycogen
## Footnote
Both are composed of alpha-glucose.
169
What is starch's primary function?
Energy storage material in plants
## Footnote
Plants store excess glucose as starch.
170
What are the two components of starch?
Amylose and amylopectin
## Footnote
Both are polysaccharides of alpha-glucose.
171
Describe amylose.
A long, unbranched chain of glucose with 1-4 glycosidic bonds
## Footnote
Its coiled structure makes it compact for storage.
172
Describe amylopectin.
A long, branched chain of glucose with 1-4 and 1-6 glycosidic bonds
## Footnote
Side branches allow quick glucose release.
173
What is glycogen's primary function?
Energy storage material in animals
## Footnote
Animals store excess glucose as glycogen.
174
How does glycogen differ from starch?
Glycogen has more side branches than amylopectin
## Footnote
This allows for quicker glucose release.
175
What is the significance of glycogen being insoluble in water?
It prevents cells from swelling by osmosis
## Footnote
This characteristic is important for storage.
176
What two monosaccharides form lactose?
Beta-glucose and galactose
## Footnote
Lactose contains a 1-4 glycosidic bond.
177
What two monosaccharides form sucrose?
Alpha-glucose and fructose
## Footnote
Sucrose contains a 1-2 glycosidic bond.
178
Fill in the blank: A polysaccharide is formed when more than _______ monosaccharides join together.
two
179
What are triglycerides?
Triglycerides are a kind of lipid made of one molecule of glycerol with three fatty acids attached to it.
## Footnote
Triglycerides are the main form of fat stored in the body.
180
What is the basic structure of a fatty acid?
All fatty acids consist of a hydrocarbon 'tail' and a carboxylic acid group. The tail varies in length.
## Footnote
The tail is often represented by the letter R in diagrams.
181
What is the difference between saturated and unsaturated lipids?
Saturated lipids do not have double bonds between carbon atoms, while unsaturated lipids do.
## Footnote
Unsaturated lipids can be further classified into monounsaturated and polyunsaturated based on the number of double bonds.
182
Where are saturated lipids primarily found?
Saturated lipids are mainly found in animal fats, such as butter.
## Footnote
Examples include meats and dairy products.
183
Where are unsaturated lipids primarily found?
Unsaturated lipids are mostly found in plants, such as olive oil.
## Footnote
Other sources include nuts and fish.
184
What happens to triglycerides during condensation reactions?
Three fatty acids and a single glycerol molecule are joined together by ester bonds, releasing a molecule of water.
## Footnote
This is the process of forming triglycerides.
185
What is the process called that breaks triglycerides apart?
Hydrolysis reactions break triglycerides apart by adding a molecule of water to each ester bond.
## Footnote
This results in the formation of three fatty acids and one glycerol molecule.
186
What is cholesterol?
Cholesterol is a type of lipid made in the body that is necessary for normal functioning.
## Footnote
Cholesterol is also a precursor for steroid hormones and vitamin D.
187
What are the two types of lipoproteins?
* High Density Lipoproteins (HDLs)
* Low Density Lipoproteins (LDLs)
## Footnote
HDLs are considered 'good' cholesterol, while LDLs are often referred to as 'bad' cholesterol.
188
What is the function of High Density Lipoproteins (HDLs)?
HDLs transport cholesterol from body tissues to the liver for recycling or excretion, reducing total blood cholesterol.
## Footnote
This process helps maintain cardiovascular health.
189
What is the function of Low Density Lipoproteins (LDLs)?
LDLs transport cholesterol from the liver to the blood, increasing total blood cholesterol when levels are too low.
## Footnote
High levels of LDLs are associated with an increased risk of cardiovascular disease.
190
True or False: A diet high in saturated fat decreases the risk of developing cardiovascular disease.
False.
## Footnote
A diet high in saturated fat increases blood cholesterol levels, which is associated with a higher risk of cardiovascular disease.
191
Fill in the blank: Increased cholesterol levels are thought to increase _______ formation.
atheroma
## Footnote
Atheromas are fatty deposits that can lead to the narrowing of arteries.
192
What is the relationship between LDL cholesterol levels and cardiovascular events?
The relative risk of a cardiovascular event increases as the level of LDL cholesterol in the blood increases.
## Footnote
This indicates a positive correlation between LDL cholesterol levels and cardiovascular risk.
193
What should you consider when interpreting data on cardiovascular events?
Check if conclusions match the data and consider sample characteristics, such as gender representation and causation versus correlation.
## Footnote
For instance, data showing trends in women cannot be generalized to men.
194
Why is a large sample size important in studies?
A large sample size is more representative of the whole population and shares more characteristics of that population.
## Footnote
This increases the reliability of the study's conclusions.
195
What lifestyle changes can reduce the risk of cardiovascular disease (CVD)?
Changes include reducing saturated fat intake and maintaining a healthy weight through diet and exercise.
## Footnote
Scientific studies have linked high saturated fat diets to increased CVD risk.
196
What is the normal BMI range for adults?
The normal BMI for adults is between 18 and 25.
## Footnote
BMI is calculated using the formula: BMI = body mass (kg) / height² (m²).
197
How is waist-to-hip ratio calculated?
Waist-to-hip ratio = waist measurement (cm) / hip measurement (cm).
198
What is the significance of obesity indicators?
Obesity indicators help assess whether individuals are overweight or obese and guide lifestyle changes to reduce CVD risk.
## Footnote
Examples include waist-to-hip ratio and BMI.
199
What type of lipid is found in olive oil?
Olive oil contains monounsaturated lipids.
200
What is a polyunsaturated lipid?
A polyunsaturated lipid contains multiple double bonds in its fatty acid chains.
201
What is a lipoprotein?
A lipoprotein is a complex of lipids and proteins that transports fats in the bloodstream.
202
True or False: Smoking has been linked to an increased risk of CVD.
True.
## Footnote
Scientific research has established a connection between smoking and cardiovascular disease risk.
203
What are two examples of initiatives to encourage people to stop smoking?
* TV adverts warning about smoking risks
* NHS providing free advice and nicotine patches
204
What is the difference between high-density lipoproteins (HDL) and low-density lipoproteins (LDL)?
HDL is considered 'good cholesterol' due to its role in transporting cholesterol away from arteries, while LDL is known as 'bad cholesterol' as it can lead to plaque buildup.
## Footnote
The structure and function of these lipoproteins differ significantly.
205
How can changes in lifestyle be monitored using obesity indicators?
Obesity indicators can be used to track changes in weight and assess the effectiveness of lifestyle modifications.
## Footnote
For example, tracking BMI before and after a diet.
206
Fill in the blank: A person's waist-to-hip ratio is calculated using the formula _______.
waist measurement (cm) / hip measurement (cm)
207
Fill in the blank: BMI is calculated using the formula _______.
body mass (kg) / height² (m²)
