Topic 1 - Lifestyle, Health and Risk Flashcards
(61 cards)
What is an atheroma?
An atheroma is a fatty deposit or fatty plaque that builds up in the walls of arteries, contributing to atherosclerosis.
What are the key stages in the cascade of events that lead to atherosclerosis?
Damage to the endothelium due to high blood pressure, toxins, high cholesterol, or high blood sugar.
Inflammatory response where white blood cells accumulate in the artery wall, forming an atheroma.
Plaque formation as calcium salts and fibrous tissue build up.
Increased blood pressure as the artery narrows, making it harder for the heart to pump blood.
What are the consequences of atherosclerosis?
Atherosclerosis can lead to:
Coronary heart disease (CHD) and myocardial infarction (heart attack).
Stroke due to restricted or stopped blood flow to the brain.
Gangrene due to tissue decay.
What is an aneurysm, and how is it related to atherosclerosis?
An aneurysm is the abnormal bulging of an artery wall caused by pressure from blood buildup behind a blockage. If an aneurysm bursts, it can lead to rapid blood loss, often fatal.
What is the role of an angiogram in diagnosing atherosclerosis?
An angiogram involves injecting dye into the bloodstream to visualize blood flow through arteries using X-ray footage, helping to detect blockages or abnormalities.
Define the following terms related to atherosclerosis:
Thrombosis
Sclerosis
Myocardial infarction
Thrombosis: A blood clot.
Sclerosis: Hardening of tissues.
Myocardial infarction (MI): A heart attack caused by blocked blood flow to the heart muscle.
Why is blood clotting essential for the body?
Blood clotting is crucial for repairing damaged tissue, preventing blood loss, and protecting against pathogens.
What are some causes of fatal blood clots?
Causes include:
Lack of movement (e.g., prolonged immobility, pregnancy, surgery, obesity).
Atherosclerosis (narrowed arteries).
Snake venoms.
What is the first step in the cascade of blood clotting?
The first step is when platelets come into contact with the damaged endothelium (lining of the blood vessel).
How is thrombin formed during blood clotting?
Thromboplastin, released by activated platelets, along with calcium ions and vitamin K, activates an enzyme that converts prothrombin into thrombin.
What is the role of fibrin in blood clotting?
Thrombin catalyzes the conversion of fibrinogen (soluble protein) into insoluble fibrin, which forms a mesh that traps platelets and red blood cells to create the blood clot.
What is a sphygmomanometer used for?
A sphygmomanometer is used to measure blood pressure.
What is the difference between systolic and diastolic blood pressure?
Systolic pressure is the highest pressure during ventricular systole (when the heart contracts).
Diastolic pressure is the lowest pressure when the heart is relaxed.
What is oedema and how is it related to hypertension?
Oedema is swelling caused by excess fluid in the tissues. Hypertension increases blood pressure, causing more fluid to leak from the capillaries into tissues, leading to oedema.
What are carbohydrates made of, and what is their general formula?
Carbohydrates are made of carbon, hydrogen, and oxygen. Their general formula is C(H₂O)n.
How are disaccharides formed, and what type of bond is involved?
Disaccharides are formed by a glycosidic bond between two monosaccharides through a condensation reaction, which produces water.
Give examples of disaccharides and the monosaccharides that make them up.
Sucrose: Glucose + Fructose (in plants)
Maltose: Glucose + Glucose
Lactose: Glucose + Galactose (found in milk)
What are polysaccharides, and what are their two main functions?
Polysaccharides are long chains of monosaccharides. They function as storage molecules (e.g., starch, glycogen) and as structural compounds (e.g., cellulose in plant cell walls).
What is the structure of amylose, and how is it beneficial for glucose storage?
Amylose is a helical molecule formed by 1-4 glycosidic bonds. Its compact structure allows for the storage of more glucose.
How is amylopectin different from amylose, and why is this important?
Amylopectin has branches formed by 1-6 glycosidic bonds, which makes it easier to break down compared to amylose. This facilitates faster hydrolysis for glucose release.
What is the role of glycogen in animals, and how is its structure adapted for its function?
Glycogen is an animal storage polysaccharide with more branches than amylopectin, allowing for extremely rapid hydrolysis. This is crucial for animals with a high metabolic rate.
What is cholesterol, and where is it found?
Cholesterol is a short, simple lipid molecule and an example of a steroid. It is insoluble in water and is found in saturated fatty foods like meat, dairy, and eggs. It is also synthesized in the liver.
What is the role of cholesterol in the body?
Cholesterol helps stabilize the fluidity of cell membranes over a broader temperature range, ensuring membrane integrity.
What is the difference between HDL and LDL, and why is the HDL:LDL ratio important?
HDL (High-Density Lipoprotein): Carries cholesterol to the liver to be broken down. It is linked to unsaturated fats (good).
LDL (Low-Density Lipoprotein): Carries cholesterol to body cells. It is linked to saturated fats (bad) and can lead to cholesterol build-up in blood vessels.
You want a high HDL:LDL ratio for heart health.