Topic 1 Flashcards
How does smoking increase the chance of coronary heart disease? (4)
1) Carbon monoxide bonds to haemoglobin instead of oxygen, resulting in cell receiving less oxygen. To compensate the heart rate increases.
2) Nicotine causes adrenalin to be produced. This increases heart rate and causes vasoconstriction of the arteries. Overall blood pressure rises.
3) Chemicals in smoke damage the lining of the artery which triggers atherosclerosis
4) HDL levels reduce
How does exercise decrease the chance of CHD?
It prevents and reduces high blood pressure and raises HDL
What does exercise also decrease?
It reduces the chance of, and controls, Type II diabetes
How can jeans increase the risk of CHD
Some disorders such as (FH) causes mutations in the LDL receptors. These mutations results in LDL not being removed in the blood.
What is APOA? What happens when it’s faulty?
Protein in HDL that takes Cholesterol to the liver. Cholesterol isn’t removed, low HDL
What is APOB? What happens when it is faulty?
It moves cholesterol to cells. High LDL
What is APOE? What happens when it is faulty?
Remove excess cholesterol. Slower cholesterol reduction
How to reduce the risk of CVD?
Stop smoking, maintain blood pressure, low cholesterol, average BMI, exercise, no alcohol.
What are the three drugs taken for blood pressure?
ACE inhibitors, calcium channel blockers, diuretics.
What do ACE inhibitors do?
Reduces the levels of the hormone that causes vasoconstriction. This causes more dilation which decreases blood pressure.
What do calcium channel blockers do?
Block the calcium channels in the muscle of the artery. This prevents constriction so blood pressure reduces.
What do diuretics do?
Cause the user to urinate more, this removes excess fluids and salts. This causes the blood plasma volume and cardiac output to decrease. This results in a lower blood pressure.
What does a statin do? Side effects?
Stops the enzyme that produces LDL. Tiredness, vomiting, diarrhoea, weakness.
What does aspirin do?
Reduce the stickiness of platelets, resulting in a lower chance of a blood clot forming.
What’s an alternative to aspirin?
Clopidogrel
How does warfarin work?
Lowers the levels of vitamin K. Vitamin K is needed for the clothing cascade to be completed.
What reaction joins monosaccharides?
Condensation
What is a saccharide?
A sugar unit
What are the values for mono, di and poly
1,2,many
What breaks up do saccharides and polysaccharides?
Hydrolysis
In a condensation reaction H2O is released. What molecules out of OH,OH,H,H does it come from?
OH-OH=H2O+O
What is the general formula of monosaccharides?
(CH20)n. Where n=number of carbons.
How fast are monosaccharides absorbed?
Very fast.
What is the structure of a saccharide?
Hexagon with 1 oxygen 5 carbon.From the far right carbon it goes H+OH,H+OH,OH+H,H+HO,H+CH2OH
In a saccharide are the carbons labelled clockwise or anti-clockwise?
Clockwise
In the long chain structure of a saccharide name the bonds on the right hand side. What is the top bond? What is the bottom bond? Which is the bond that changes side if it is beta?
OH,H,H,OH. H-C=O. CH2OH. Second hydrogen chain from the bottom.
Difference between alpha and beta glucose structure?
Alpha=OH below, Beta=OH above.
What is a glycosidic bond?
The oxygen bond between two monosaccharides. -O-
What saccharide said are released slow/fast and why?
Mono=fast, di/poly=slow. This is due to the di/poly having to be digested down into mono which takes time.
What are three examples of polysaccharides? Why are they used for storage?
Glycogen, cellulose, starch. They are all compact. Furthermore, they are all insoluble so will not effect the water concentration and therefore not effect osmosis.
Where is glycogen stored in humans?
Liver/muscles.
How is cholesterol made soluble?
It is combined with proteins.
What is the good type of cholesterol called?
HDL
What are the roles of LDL and HDL?
HDL transports cholesterol from the body tissue to the liver where is it broken down so cholesterol levels reduce. LDL cholesterol travels to the membrane where it overloads the receptors and causes high cholesterol levels. This can cause athleromas In the artery wall.
What are the features of a good study?
Clear aim, relevant sample, valid/reliable results by using the correct equipment, people able to consent as then it is less likely lies will be told, use the same equipment each time, large sample size to ensure the extremes are discounted,control variables.
What increases your risk of having CVD?
High blood pressure, obesity, high blood cholesterol levels, smoking, inactivity, genetics.
What is blood pressure?
The hydrostatic force of blood against the walls of a blood vessel.
What does it mean when blood pressure is systolic and diastolic?
Systolic is when the ventricles contract and blood is forced into the arteries. Diastolic is when the ventricles are relaxed.
What is the process of using a traditional blood pressure machine?
The inflatable cuff cuts the blood flow in the artery of the arm. The pressure is slowly released and blood flows back in. The pressure is still released until a noise is heard on the stethoscope placed on the artery. This is systolic.
For diastolic the pressure is continually dropped until no noise can be heard, this reading is the diastolic pressure.
What is blood pressure measured in?
Is unit is Kilopascal, traditionally it was measured in mmHg.
What are the normal pressures of blood?
100-140 systolic, 60-90 diastolic.
What is peripheral resistance?
Resistance caused by the contact between blood and the walls.
What can cause high blood pressure (example)? What happens?
Age, hormones such as adrenalin, high salt levels. The smooth muscle contracts which narrows the lumen causing a higher pressure.
What is oedema?
The condition is swelling caused by a fluid build up.
What is Oedema a sign of?
High blood pressure.
How are small molecules and fluid removed from the blood?
When arterioles transition to capillaries there is a high pressure of blood. This high pressure forces these molecules through gaps between the cells of the capillary wall. These molecules then form the tissue flood outside the capillary.
What is another name for tissue fluid?
Interstitial fluid.
What happens to used tissue fluid?
20% goes to the lymph vessels which returns it to the vena cava via the thoracic duct. The rest is reabsorbed into the capillaries.
What are the symptoms of coronary heart disease?
Shortness of breath, angina, left arm pain, arrhythmia.
What is arrhythmia?
An irregular heart beat.
What are the symptoms of a stroke?
Numbness, dizziness, confusion, slurred speech, blurred vision in one eye(the side will be opposite to where the clot is).
What is an aneurism?
A blood filled bulge behind the narrowing of an artery.
What happens if an aneurism bursts?
Mass blood loss and fatal shock.
How can an Aneurism be detected and treated?
Felt as a lump, or by using ultrasound. It is treated with an artificial artery replacement.
When measuring risk what must you do?
Put a timeframe on it.
What factors cause people to overestimate risk?
Involuntary, not natural, unfamiliar, dreaded, unfair, very small.
What are some health factors that contribute to risk?
Age, heredity, physical environment, social environment, lifestyle, behaviour.
What is correlation?
One factor changes as the other changes.
What is causation?
When the changing of one factor causes the increase or decrease of the other.
What is a cohort study? 2 examples
A population of people are followed with regular detailed check ups. If one of these people contract the disease they review what risk factors they were exposed to.
Secondly another type is where people are split into two groups, one is exposed to the risk factor, the other not. It is then seen if one group develops the disease.
What is a case control study?
Two groups are made; one with a disease, the other are healthy. Each individual is analysed to see what risk factors they were exposed to in their past. All risks are then compared to see if there is any correlation.
When talking about people what does the term ‘case’ mean?
A person with the disease.
Why do only arteries get atherosclerosis?
The blood is flowing very fast at a high pressure which increases the chance of damage, the veins are low pressure.
What do blood clots do? Why?
Seals breaks in blood vessels to reduce blood loss and prevent pathogens entering the body.
How do platelets change when they come into contact with a damaged vessel?
They transform from flat discs to spheres with long, thin projections.
What do platelets do to a damaged vessel?
Bind to the exposed collagen and surrounding platelets. This is a temporary platelet plug.
What is the clotting cascade process?
1) Platelets stick to the damaged wall and other platelets To form a temporary platelet plug.
2) The platelets and damages tissue release a protein called thromboplastin
3) Thromboplastin activates the enzyme that catalysis prothrombin to the enzyme thrombin. This reaction requires calcium ions and vitamin K.
4) Thrombin catalysis soluble fibrinogen to insoluble fibrin.
5) Fibrin forms a mesh around the damaged area that traps more platelets and red blood cells. This results in a clot being formed.
Why does blood not usually clot in the blood vessels?
The smooth endothelium has substances on the surface that repels platelets.
What could limiting the amount of blood to the heart cause? Why?
Angina. The cardiac muscle has to work harder and respire more but only has a limited amount of oxygen. This results in anaerobic respiration.
What happens if a plaque ruptures?l
Collagen is exposed which triggers the clotting cascade.
When is a heart attack more deadly?
When more of the heart is ischaemic due to an atheroma higher in the coronary artery.
What does ischaemic mean?
Without blood.
How is a mini stroke different from a full stroke?
The effects last for a shorter period of time and recovery happens quickly.
What causes a mini stroke? What causes a full stroke?
A mini stroke is when the blood to the brain is briefly interrupted. A full stroke happens when the blood flow is blocked for a period of time.
What is cardiac diastole?
The atria and ventricles relax, lower pressure inside the heart. Blood is forces into the hearts atria, valves prevent the ventricles filling. The coronary arteries also fill during cardiac diastole.
What is the equation for heart rate?
60 seconds/time taken for 1 cardiac cycle.
What is atherosclerosis?
The process that leads to coronary heart disease or strokes.
What happens during atherosclerosis?
Fatty deposits build up in an artery and can either block their artery or lead to the artery being blocked by a blood clots as the lumen is smaller and can withstand less damage.
What is it called when something is blocked by a blood clot?
Thrombosis
What happens when the blood supply to the heart is blocked?
A heart attack
What happens when the blood supply to the brain is blocked?
A stroke
What happens if there is a narrowing of the arteries in the leg?
Tissue death and gangrene
What can happen in a blocked artery?
It can burst.
What is the process of atherosclerosis?
1) The endothelium becomes damaged, this can be caused by high blood pressure or toxins from cigarette smoke.
2) An inflammatory response happens where white blood cells move to the damaged area. They accumulate chemicals from the blood such as cholesterol.
3) This causes an atheroma.
4) Calcium salts and fibrous tissue build up at the site. This causes a hard welling called a plaque.
5) The fibrous tissue causes the artery to lose elasticity and harden
6) The plaque causes the lumen to decrease in size, this makes blood pumping hard and blood pressure can increase.
7) This is positive feedback as atherosclerosis increases blood pressure and high blood pressure causes atherosclerosis.
What is positive feedback?
A factor causes another factor to increase, but this increase in the second factor also causes an increase in the original factor
During systole where is blood forced? How does it accommodate this change?
Arteries. By expanding due to the elastic fibres.
In systole is the heart contracting or relaxing?
Contracting.
In diastole is the heart contracting or relaxing?
Relaxing.
What happens in the arteries during diastole?
The walls recoil behind blood which pushes it forward smoothly.
Is pressure in the capillaries higher or lower than the arteries? Why?
Lower. Friction due to the smaller size.
Why is the speed in the capillaries beneficial?
It allows more exchange between blood and cells/alveoli.
Is pressure in the veins low or high?
Low
How is blood flow assisted in the veins?
The muscles contract to push the blood, valves prevent back flow, and the lower pressure in the thorax during inhalation helps.
What type of valves are in the vein?
Semilunar
What is needed in aerobic respiration?
Oxygen and glucose
Definition of the cardiac cycle?
One cycle is the filling and pumping of blood.
In simple terms what happens during systole?
Cardiac muscle contacts, this causes blood to be pumped into the aorta and pulmonary artery
In simple terms what happens during diastole?
Cardiac muscles relax and the heart fills with blood.
What are the three phases of the cardiac cycle?
Atrial systole, ventricular systole, diastole.
What happens in atrial systole?
The Arita contract and force blood into the ventricles.
What happens in ventricular systole?
The ventricles contract and force blood into the aorta and pulmonary artery.
What is cardiovascular disease?
Disease of the heart and circulation
What are the two most common forms of CVD?
Stroke and coronary heart disease.
What is an open circulatory system?
Blood circulates in a large area where it diffuses and then travels back to the heart
What is a closed circulatory system?
Blood is enclosed in blood vessels.
What is the order of blood vessels?
Artery, arterioles, capillaries, venules, veins.
What is a single circulatory system? Example?
The blood passes through the heart once. Fish
What is a double circulatory system? Example?
Blood passes through the heart twice. Humans/large mammals.
What are the benefits of high pressure blood?
High metabolic rate?
What substances are carried in the plasma?
Glucose, oxygen,carbon dioxide.(main) proteins, salts, enzymes, hormones, antibodies.
How are internal temperatures maintained?
Water requires a lot of energy to heat, so the temperature only varies lightly.
What is the heart made of?
Cardiac muscle.
What do the atrioventricular valves connect?
The atria to the ventricles.
What so the semilunar valves connect?
Ventricles and the aorta/pulmonary artery.
When blood passes through the heart what is the order of components?
Vena Caver, right atrium, rights atrioventricular valve, right ventricle, right semilunar valve, pulmonary artery, lungs, pulmonary veins, left atrium, left atrioventricular valve, left ventricle, left semilunar valve, aorta.
What is the apex of the heart? Where?
The thickest part. Base on left.
What are the structural components of a blood vessel?
Collagen, elastic fibres,smooth muscle.
What is starch made of?
Amylose, amylopectin
What is starch made of?
Amylose, amylopectin.
What are the differences in the structure of amylopectin and amylose?
Amylopectin has branches.
Why is glycogen a good energy?
Multiple side branches mean it’s hydrolysed quickly which releases fast energy.
How is cellulose used in humans?
It is indigestible so is a dietary fibre which aids the movement of digestion.
What is cellulose thought to stop?
CHD, diabetes, bowel cancer.
What is a haemorratic stroke?
Blood vessels burst in the brain.
What do lipids do?
Enhance flavour and palatability.
What do lipids allow? E.g.
Lots of energy in a small mass. E.g. Seeds.
What are lipids solubility?
Insoluble in water, soluble in organic solutions e.g. Ethanol.
What are most of the lipids we eat?
Triglyceride.
What is the structure of a triglyceride? Use?
3 fatty acids. One glycerol. Linked by condensation. Energy stores.
What is the bond between a fatty acid and a glycerol called?
Ester bond.
How many ester bonds are in a triglyceride?
3
What does the ester bond involve?
O-C=O
What is the structure of a fatty acid?
Hydrocarbon with carboxylic group.
Simplified structure?
Skeletal with carboxylic group.
What are the sources of saturated fats?
Meat, dairy.
Why are fats solid at room temperature?
Saturated fats are tightly packed as they are straight. This creates strong intermolecular forces that are hard to break so more energy is required to form a liquid.
Where does the double bond have to be for the fat to be unsaturated?
The hydrocarbon chain.
What is the difference between mono and poly unsaturated?
Mono- one double bond. Poly- many.
Why are unsaturated fats liquid at room temperature?
Kinks caused by double bonds prevent tight packing. This results in wear intermolecular forces that are easily broken to result in a liquid state.
What oil is high in monounsaturated fats?
Olive oil.
Sources of polyunsaturated fats?
Other oils, fish, nuts.
How can unsaturated fats become saturated?
Adding hydrogen
Name of unsaturated fats which have added hydrogen? Uses?
Hydrogenated/trans fats. Processed food.
What is made from cholesterol?
Progesterone, testosterone, bile salts.
What are bile salts used for?
Lipid digestion.
Where is cholesterol made and what from?
Liver, unsaturated fats in diet.
What food is cholesterol in?
Eggs, meat, dairy.
What do fats also do?
Supply essential fatty acids.
What does a deficiency of linoleic acid cause?
Scary skin, hair loss, slow healing.
What is the basal metabolic rate?
The energy needed for essential processes.
What body processes are essential?
Heart pumping and beating, breathing, maintaining temperature.
Who is the BMR higher in?
Young, heavy, male, active people.
What does the positive/negative energy Balance mean?
Positive- too much energy input gain weight. Negative- little energy input. Lose weight.
BMI equation?
Kg/height ^ squared
BMI boundaries?
<18.5 underweight. 25+overweight. 30+ obese.
What does waist to hip ratio show?
Higher means a higher risk of a heart attack.
Equation of hip to waist ratio?
Circumference of waist/Circumference of hip.
What leads to obesity?
Inactivity, high sugar/ fat diet.
What does obesity increase the risk of?
CHD, stroke, type 2 diabetics.
What happens in type 2 diabetes.
Constant high rate of glucose so there is no response to insulin or insulin isn’t produced.
