Topic 1: Lifestyle, Health, and Risk Flashcards
Define diffusion.
Diffusion is the movement of particles from high to low concentration.
What is mass flow?
Mass flow is the bulk movement of substances over relatively long distances, due to pressure differences.
What do mass transport systems do?
Mass transport systems move substances to and from exchange surfaces.
What are the 5 types of blood vessels?
Arteries, Arterioles, Capillaries, Venules, and Veins.
What is the inner layer in a blood vessel called, and what does it do?
It is called the endothelium (tunica intima), and it provides a smooth passage for blood to flow through.
What is the middle layer in a blood vessel called, and what does it do?
The middle layer is called the tunica media, and it is made of smooth muscle which contracts, and it has elastic fibres, which recoils in order to withstand the high blood pressure.
What is the outer layer in a blood vessel called, and what does it do?
It is called the tunica adventitia, and it is the connective tissue, which is high in collagen.
What is the gap in the middle of the blood vessel called, and what does it do?
It is called the lumen, and it is the passage for the blood to flow through.
What is collagen?
Collagen is a key structural protein, which makes up 25-30% of the body’s protein content.
What makes blood flow in the thinner-walled veins?
Blood flows in the veins due to pressure from skeletal muscles.
Which chamber of the heart has the thickest wall and why?
The left ventricle has the thickest wall, because it needs to pump blood throughout the whole body.
What happens during cardiac diastole?
Blood flows into the atria, from the vena cava and pulmonary vein, with closed atrioventricular valves.
What happens during atrial systole?
The pressure increases in the blood-filled atria, pushing the atrioventricular valves open, and the blood flows into the ventricles. Then, the atria both contract, forcing all of the blood into the ventricles.
What happens during ventricular systole?
The ventricles contract, which forces the atrioventricular valves to close, and the semilunar valves to open, forcing blood into the pulmonary artery and aorta.
What is atherosclerosis?
Atherosclerosis is the process that causes arteries to become too narrow.
What is the 1st stage of atherosclerosis?
The endothelium becomes damaged and dysfunctional.
What is the 2nd stage of atherosclerosis?
Macrophages leave the blood vessel and move into the artery wall.
What is the 3rd stage of atherosclerosis?
Calcium salts and fibrous tissue builds up, resulting in a hard swelling called plaque and the inner wall of the artery.
What is the 4th stage of atherosclerosis?
The lumen becomes narrower due to the plaque, which can cause high blood pressure.
What is the 1st stage of thrombosis?
Platelets and damaged tissue release a protein called thromboplastin.
What is the 2nd stage of thrombosis?
The thromboplastin activates an enzyme which catalyses the conversion of prothrombin into an enzyme known as thrombin.
What is the 3rd stage of thrombosis?
Thrombin catalyses the conversion of fibrinogen into fibrin.
What is the 4th stage of thrombosis?
A mesh of fibrin forms, which traps more platelets and red blood cells, forming a blood clot.
What does it mean if a substance is non-polar?
It is hydrophobic, and doesn’t dissolve in water
What does it mean if a substance is polar?
It dissolves in water (soluble).
What is specific heat capacity?
How slowly/quickly water heats up.
What type of bonds link the hydrogen and oxygen together in water molecules?
Covalent bonds.
What do the oxygen molecules do to the hydrogen atoms in water molecules, and what is the result of this?
The oxygen atom becomes slightly negatively charged and the hydrogen atoms become slightly positively charged.
Why are water molecules ‘sticky’?
Because of the hydrogen bonds between them, and this cohesion causes surface tension.
What types of animals have an open circulatory system?
Insects, molluscs.
What types of animals have a single circulatory system?
Fish, invertebrates, amphibians.
What types of animals have a double circulatory system?
Birds, mammals
What are arteries?
Arteries are a type of blood vessel that have a narrow lumen and a large tunica media in order to withstand high blood pressure.
What do arteries do?
Arteries carry blood away from the heart, with deoxygenated blood going to lung capillaries, and oxygenated blood going to body capillaries.
What are veins?
Veins are a type of blood vessel that have a wide lumen, in order to reduce blood pressure.
What do veins do?
Veins carry oxygenated blood to the heart through the pulmonary vein, and deoxygenated blood to the heart through the vena cava.
What are capillaries?
Capillaries are a type of blood vessel that have walls that are 1 cell thick, and they are all at most 2 cells away from body cells.
What do capillaries do?
Capillaries pick up waste products from cells, and they deliver nutrients, and oxygen to those cells.
What is a hazard?
Anything that can potentially cause harm.
What is a risk?
The likelihood of an event which can cause harm happening.
What effect does pressure have on blood flow?
As the pressure increases, the blood flow decreases.
What effect does lumen radius have on blood flow?
As the lumen radius increases, so does the blood flow.
What effect does vessel length have on blood flow?
As the vessel length increases, the blood flow decreases.
What effect does viscosity have on blood flow?
As viscosity increases, blood flow decreases.
What is a cohort study?
In a cohort study, a group of people are followed over time to see who develops a specified disease.
What is a case-control study?
In a case-control study, a group of people with a specified disease get compared to a group of people without that disease
What are the 6 risk factors for CVD?
High blood pressure, obesity, blood cholesterol, smoking, inactivity, genetic inheritance.
Which age group tends to be more susceptible to CVD?
75+
Which gender tends to be more susceptible to CVD?
Men
What is blood pressure a measure of?
Hydrostatic force of the blood against walls of a vessel.
What is the name of the machine which measures high blood pressure?
Sphygmomanometer
What is the average healthy person’s blood pressure?
Systolic pressure of 100mmHg - 140hhMg
Diastolic pressure of 60hhMg - 90mmHg
What is a calorie?
The quantity of heat energy required to raise the temperature of 1cm^3 of water by 1°C.
How many joules are in a calorie?
4.18J
How much energy per gram/kJ is available in carbohydrates?
16
How much energy per gram/kJ is available in lipids?
37
How much energy per gram/kJ is available in proteins?
17
How much energy per gram/kJ is available in alcohol?
29
What is a monosaccharide?
A single sugar unit
What is a diasaccharide?
2 sugar units that have combined in a condensation reaction
What is a polysaccharide?
Many sugar units in one long chain
