TOPIC 1: Lifestyle and Risk Flashcards
Explain why high blood pressure can increase the risk of developing CVD (3)
- high blood pressure causes damage to endothelium of arteries
- built up of cholesterol leads to formation of atheroma
- plaque develops and narrows lumen of the artery
Explain why a mammal born with a hole between two ventricles will have these symptoms (3)
- less oxygen available for aerobic respiration
- deoxygenated blood mixes with oxygenated blood
- therefore reducing concentration of oxygen in blood circulating the body
Explain how the diet of a person could affect the development of CVD (4)
- higher salt intake
- increases blood pressure
- high intake of saturated fat
^ linked to plaque formation
Describe the role of LDLs in the development of atherosclerosis (3)
- cholesterol in the blood
- is deposited to form atheroma
- in the endothelium of an artery
Explain how atherosclerosis can result in damage to the heart muscle (2)
- narrowing of coronary arteries
- which reduced blood flow to the cardiac muscle
Describe the role of thrombin in blood clotting (3)
- thrombin is an enzyme
- which catalysed the conversion of fibrinogen into fibrin
- a mesh of fibrin traps platelets to form a clot
Explain why a mutation in the gene coding for the protein factor V may increase the risk of VTE (3)
- mutation in gene changes the sequence of amino acids
- increases production of thrombin
- increases blood clotting
Explain how a blood clot could form in a blood vessel (4)
- collagen is exposed when the wall of a blood vessel is damaged
- leading to release of thromboplastin
- thromboplastin catalysed conversion of prothrombin into thrombin
- thrombin catalysed conversion of fibrinogen into fibrin
Explain why tranexamic acid will result in reduced blood loss during surgery (3)
- fibrin forms a mesh that collects platelets
- tranexamic acid stops the breakdown of fibrin
- allowing clots to remain in place
Explain how very high blood pressure could result in atherosclerosis (4)
- high blood pressure damages endothelium of an artery
- causing an inflammatory response
- atheroma forms
- calcium salts & fibrous tissue build up
Explain how atherosclerosis in one part of an artery could increase the likelihood of it developing in another part of the same artery (2)
- plaque narrows the lumen
- further increases blood pressure
Explain why platelet inhibitors would reduce the risk of a heart attack (2)
- reduce the risk of blood clots forming
- therefore less likely that blood flow to heart muscle will be blocked
Explain the file of antihypertensive drugs in reducing the risk of atherosclerosis (4)
- lower blood pressure
^ reduced risk of damage to endothelium of artery
- reduced risk of inflammatory response
- reduced risk of atheroma
State two possible side effects of taking drugs to reduce blood pressure (2)
- nausea
- kidney failure
Explain why beta-blockers are prescribed for some people (2)
- reduce blood pressure
- reducing risk of CVD
Describe how glucose moves into cells by facilitated diffusion (2)
- glucose binds to carrier proteins in cell surface membrane
- and moves from a high to low concentration
Explain how the structure of glycogen allows it to be an energy store (3)
- branched: rapid hydrolysis
- compact: large amount of energy able to be stored in small space
- provides glucose for respiration
Describe the reaction that joins two a-glucose molecules to form a disaccharide (2)
- condensation reaction
- involving OH groups on both molecules
Compare and contrast the structures of trehalose and maltose (2)
- both contain a glycosidic bond
- in trehalose, one of the glucose monomers is inverted
Give one structural difference between amylose and amylopectin (1)
- amylose is unbranched
Explain how the structures of amylopectin and glycogen make them suitable for storing energy (3)
- branched: can be rapidly hydrolysed
- compact: more energy can be stored in a small space
- insoluble: doesn’t affect osmosis
Explain the advantage of insects storing both trehalose and glycogen (4)
- glycogen is a polymer of glucose
^ & is very branched so releases glucose rapidly
- the breakdown of trehalose provides more of an immediate source of glucose
- glucose is used in respiration to provide energy
Explain the effect that large quantities of this lipoprotein would have on blood cholesterol levels (4)
- increased blood cholesterol
^ bcs the triglyceride is saturated
^ & this lipoprotein is an LDL
^ and LDLs transport cholesterol
State the type of reaction where two monosaccharides join to form a disaccharide molecule (1)
- condensation reaction
Name the two monosaccharides that are produced when sucrose is broken down (1)
- glucose
- fructose
Compare and contrast the structure of a disaccharide with glycogen (4)
SIMILARITIES:
- both contain carbon, hydrogen & oxygen
- both contain glycosidic bonds
- both contains glucose
DIFFERENCES:
- glycogen has 1,4 and 1,6 glycosidic bonds but disaccharides only have 1 type of glycosidic bonds
Describe how an enzyme could break down the polysaccharide component of monopolysaccharides (2)
- hydrolysis
- of glycosidic bonds
Describe the structure of an unbranched polysaccharide (2)
- joined together by glycosidic bonds
- only 1,4 glycosidic bonds present
Describe the formation of glycogen from glucose (2)
- joined together in condensation reactions
- forming 1,4 and 1,6 glycosidic bonds
Explain why high levels of sugars in a person’s diet could lead to obesity (3)
- energy intake is higher than energy output
- excess sugars can be stored as fat
^ leading to weight gain
A student stated that loss of heat when sweating is related to the dipole nature of water molecules.
Justify this statement. (3)
- water has an uneven distribution of charge
- forms h-bonds with other water molecules
- lots of heat is required to break these bonds
Explain how the properties of water make it an ideal transport medium. (3)
- water is a solvent
- because water molecules surround polar molecules
- water is a liquid, so has ability to flow
Name the type of reaction in which a molecule of water is involved in the breaking of a bond in another molecule. (1)
- hydrolysis
Compare and contrast the heart and circulatory system of a snake with that of a human. (4)
similarities:
- both have a double circulatory system
- both have 2 atria, veins, arteries and capillaries
differences:
- snake heart has one ventricle, human heart has two
- in snake heart, deoxygenated and oxygenated blood mix. in human heart, they do not
Explain why a snake needs a heart. (2)
- to supply oxygen to body cells
- by mass transport
Determine why animal A does not need a circulatory system but animal B does. (4)
- both have the same volume
- animal A has a larger surface area
^ and a larger surface area : vol ratio
- so sufficient s.a in animal A for diffusion
State and explain one feature of capillaries that helps them carry out their functions. (2)
- walls are one cell thick
^ provides short diffusion pathway to reach body cells
Explain why multicellular organism, such as humans, require a circulatory system while single-celled organisms, such as bacteria, do not. (2)
- multicellular organisms are made up of many layers of cells
- the diffusion pathway to cells deep in the body would be too far
Describe what is meant by a mass transport system. (1)
- the bulk movement of gases or liquids in one direction, usually via a system of vessels and tubes.
Using a named example, explain the benefits of the circulatory system as a mass transport. (3)
- the lungs & circulatory system
- faster transport of oxygen from the lungs
- faster removal of CO2 from respiring cells to lungs
Describe one structure of an artery and a vein and how this structure relates to its function. (2)
- artery: narrow lumen
^ withstands high blood pressure - vein: valves
^ prevents back flow of blood
Explain the blood pressure in the following: (5)
i) the arteries and arterioles
ii) the capillaries
iii) the venules and veins
i) - higher blood pressure because contractions of heart force blood into arteries at high pressure
- narrow lumen maintains high b.p
- pressure increases when heart contracts and decreases when heart relaxes
ii) pressure decreases because friction increases b/w capillary walls and blood
iii) blood pressure decreases bcs greater distance b/w veins and heart
Explain one property of water that makes it an ideal transport medium for organisms with a transport system. (2)
- acts as a solvent
^ can transport dissolved substances in blood e.g. glucose
Explain the role of hydrogen bonding and its importance in transporting water. (2)
- allows water molecules to stick together
- H-bonds form b/w other molecules and water
Explain how valves work. (2)
- prevent back flow of blood
- e.g. right AV valve prevents blood returning to right atrium from right ventricle
Name which part of the heart causes the increase in pressure in the aorta.
left ventricle
Explain why increasing pressure in the aorta is important for the organism. (3)
- ensures blood is leaving heart under high pressure
- so oxygen is delivered to cells
- for aerobic respiration
Discuss the ethical issues when using organisms such as Daphnia
- organisms cannot communicate when they feel pain or discomfort
Name two precautions that need to be taken when using live organisms during an experiment. (2)
- handle organisms with care
- wash hands after handling
State and justify a suitable control for this investigation involving Daphnia (2)
- water
- to compare with caffeine solutions
Describe the role of ester bonds within lipids and the mode of ester bonds’ formation and breakage. (3)
- to link fatty acids and glycerol
- formed by condensation
- resulting in a water molecule being a by-product
Compare and contrast the structures of saturated and unsaturated fatty acids. (4)
similarities:
- both have hydrocarbon tails
- both have carboxylic acids
differences:
- unsaturated has C=C double bonds
- saturated has straight chains
Describe how the misuse of alcohol can result in an increased risk of CVD. (2)
- can increase blood pressure
- this can put a strain on artery walls, increasing the risk of an atheroma
Explain how a diuretic may reduce blood pressure and relieve the symptoms. (2)
- more plasma leaves the body
- reduced blood volume
Compare and contrast the structure of alpha and beta glucose. (4)
similarities:
- both have hexose sugars
- both have a ring structure
differences:
- alpha has H above Carbon-1 & OH below
- beta has H below Carbon-1 & OH group above
State why the properties of glucose make it a good molecule for its roles:
- small
- high ability to polymerise
- high solubility in water
- high energy content
- small: easily transportable
- high ability to polymerise: good for storage compounds e.g. glycogen
- high solubility in water: easy transport in aqueous systems
- high energy content: high energy yield
State two features of a glycosidic bond that forms between two monosaccharides in a condensation reaction. (2)
- strong covalent bond
- acts as a bridge via one oxygen atom
State two features of starch and how they allow starch to act as a storage substance. (4)
- branched chain
^ fast breakdown - insoluble
^ doesn’t affect water potential
Explain what 25% of the energy of the total BMR is principally released for. (2)
- keeping neurones polarised
- by active transport
Explain how the hole in the septum allowed this baby to survive. (3)
- hole allows oxygenated and deoxygenated blood to mix
- oxygenated blood travels to body
- providing some oxygen for respiration
State the type of vessel with no collagen in its wall
capillary
Describe the Daphnia practical. (5)
- Daphnia immobilised on cavity slide
- acclimatisation time in caffeine solution
- use counter to count heart rate
- use Daphnia of same size
- repeat & calculate mean
Name the valves in the heart. (2)
- atrioventicular valve
- semilunar valve
Explain how pressure differences in the heart ensure efficient pumping of the blood into the arteries. (3)
- pressure increases in ventricles
- greater pressure in ventricles than atria
- causing atrioventricular valves to close
Explain the changes in blood pressure during this part of the cardiac cycle. (4)
- pressure increases due to atrial systole
^ ventricles fill w/ blood
- after atrial systole finishes, there’s a fall in ventricular pressure
- pressure increases due to ventricular systole
