Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

Biology Edexcel Alevel > Topic 1 > Flashcards

Topic 1 Flashcards

1
Q

What is a CVD and give examples

A

CVD is a disease affecting heart and circulation
Stroke and CHD

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

What is mass flow (larger organism)

A

Particles in a liquid move in one direction due to change in pressure

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

Define open circulatory system

A

Simple heart pumps blood between cavities, substances diffuse between blood and cells. When relaxed blood drawn back.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

Define closed circulatory system

A

1)Blood leaves heart under pressure and flows along arteries to capillaries
2)Substances exchanged
3)After capillaries blood returns to heart via veins

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

Single circulatory system

A

Blood only passes past heart once for each complete circuit

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

Double circulatory system

A

—> Right ventricle-deoxygenated blood flows to lungs to receive oxygen
—>Left ventricle-oxygenated blood flows to rest of body to give oxygen

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

Why is water a good transport medium (liquid transporting ions/molecules)

A
  • easily dissolves molecules that are polar (hydrophilic) and molecules held by ionic bonds
  • it has a high specific heat capacity and is a liquid at room temperature as it has strong H+ bonds.
  • Water is polar as one end is positive (H+) and the other negative (O-) forming a dipole.
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

Structure of arteries (blood away from heart)

A

-Thick wall (withstand high BP)
-Smooth walls (ease blood flow)
-Elastic walls (recoil blood)
-endothelium cells (Lower friction)
-narrow lumen

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

Structure of vein (blood to heart)

A

-Thin walls
-Valves (stop back flow of blood)
-Wide lumen
-Little smooth/elastic muscles

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

Structure of Cappilaries

A

-Narrow lumen
-One cell thick (for shorter diffusion distance)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

Steps of cardiac cycle

A

1)Atrial systle- blood under low pressure flows into left/right aria from pulmonary veins and vena cava. Atria fills up opening AV so blood flows into ventricles.
2)Ventricular systle- Ventricles contract opening SV and blood goes into pulmonary artires ( from right ventricle) and aorta (from left ventricle).
3)Cardiac diastole- atria and ventricles relax and blood from pulmonary arteries and aorta goes back into ventricles closing SV. Conary artires fill and blood is drawn into heart via viens.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

Describe atherosclerosis

A

1) Endothelium becomes damaged (i.e by high BP) and there is an inflammatory response
2)White blood cells move into artery walls. Over time there is a build up of cholesterol,calcium and fibres build up and harden leading to atheroma (plaque) forming.
3) Arteries narrow and lose elasticIty so again high BP and there is a positive feedback loop

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

Why and how does the heart get its own supply of O2

A

Heart is a muscle so needs O2/glucose for aerobic respiration. Conary arteries supply heart with blood (O2)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

Risk factors for atherosclerosis

A

-Age (arteries become less elastic)
-Diet (more cholesterol in poor diet)
-High BP (damage endothelium)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

Blood clotting (thrombosis) steps

A

1)Platelets and damaged tissue release thromboplastin
2)Thromboplastin activated enzyme that catalyse prothrombin into thrombin (needs to be Vitamin K and calcium for this)
3)Thrombin catalyses fibrogen in fibrin
4)mesh of fibrin traps platelets/red blood cells to form clot

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

What does ischaemic men

A

Without blood

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

What is angina

A

Chest pain caused when heart has to respire anerobically at it is starved of O2

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

What is risk and how can it be overestimated

A

Risk-probability of occurrence of some unwanted event
Can be over/under estimated as:
Involuntary/not natural/unfair/unfamiliar/small

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

What is correlation

A

When a change in one factor is accompanied by a change in another

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

What is causation

A

When a change in one factor causes a change in another

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

What is a cohort study

A

Follow large groups over time. Monitor to see who develops condition and interview to find correlation between risk factors.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

What is case control study

A

Group with and without condition interviewed about past histories to work out risk factors.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

Features of a good study

A

Clear aim
Good sample size
Control variables
Good sample size

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
Q

What is high BP known as and how is it measured

A

Hypertension and measured with a sphygmomanometer

25
Q

What is oedema

A

Sign of high BP it’s fluid building up tissue causing swelling

26
Q

How are disaccharides formed

A

Joining of two monosaccharides (simple sugar molecule) in a condensation reaction (removing water), joined by glycosidic bonds. They can be split by hydrolysis (adding water).

27
Q

How is Maltose/Sucrose/lactose (disaccharides) made

A

—>Maltose-Condensation of two glucose molecules
—>Sucrose-Condensation of glucose+fructose
—>Lactose-Condensation of glucose+glactose

28
Q

What are polysaccharides

A

Polymers made up of simple sugar monomers joined by glycosidic bonds into long chains. Act as energy stores as compact with low solubility in water.

29
Q

What is starch made up of

A

Amylose (unbraced chain of glucose join by 1,4 glycosidic bonds) and amylopectin (polymer of glucose with branches joined by 1,4 and 1,6 glycolic bonds)

30
Q

What is glycogen

A

Polysaccharide used by bacteria instead of starch as an energy store. It has many branches (1,4 and 1,6 glycosidic bonds) so rapidly hydrolysed, so energy released quickly . In humans stored in liver and muscle cells.

31
Q

What are lipids

A

Biological molecules only soluble in organic solvent (alcohol)

32
Q

Saturated lipids

A

No double carbon (animal fats)

33
Q

Unsaturated fats

A

One double carbon bond. Melt at lower temperatures as intermolecular forces are weaker. Double bond makes lipid weaker as it created a “kink”.

34
Q

Properties of lipids

A

-waterproof as fatty acid tail hydrophobic
-compact so better energy release than carbohydrates and proteins
-conduct heat slowly so provide thermal insulation

35
Q

What is triglycerides

A

Made of one molecule of glycerol and 3 fatty acids joined by ester bonds in condensation reaction. Used as energy release in plants/animals.

36
Q

How can fats help

A

Provide energy and essential fatty acids that body can synthesise

37
Q

What is Basal metabolic rate

A

Energy needed for essential processes
Higher in: -males
-younger people
-more active people

38
Q

BMI calculation

A

BMI=mass/height^2
-18 or below= underweight
-30 or above =overweight

39
Q

Features of LDLs (bad cholesterol)

A

They bind to cell surface receptors which can become saturated leaving LDLs in the blood. They are associated with atherosclerosis development and be maintained at a low level.

40
Q

Features of HDLs (good cholesterol)

A

They transport cholesterol from body tissue to the liver where they are broken down. HDLs lower cholesterol levels and should be maintained at a low level.

41
Q

How can different types of fat affect HDL and LDL levels

A

—>Saturated fats (bad fat)- increase both LDL and HDL levels but increased LDLs at a higher rate.
—>Unsaturated fats (better fats)-decrease both but decrease LDLs more

42
Q

How can smoking affect circulatory system

A

-Carbon monoxide in smoke binds to haemoglobin (O2 carrying cell), reducing O2 supply to cells. This can increase heart rate.
-Nicotine stimulate release of adrenaline. This increase heart rate and causes arteries to constrict both raising BP.

43
Q

How can moderate exercise decrease risk of developing CVDs

A

-prevent high BP
-maintain good weight
-increase HDL levels

44
Q

What are apolipoproteins

A

Protein component of lipoproteins. Formed in liver and intestines and important in stabilising lipoprotein structure named recognising receptors.

45
Q

Apolipoproteins A mutation

A

Mutation associated with low HDL levels and less cholesterol removal

46
Q

Apolipoproteins B mutation

A

Higher LDL and susceptibility to CVDs

47
Q

Apolipoprotein E mutation

A

APOE is a major proteins in HDLs and vLDLs

APOE4 mutation associated with slower removal of cholesterol

48
Q

How can vitamin c (citrus fruits) help body

A

Antioxidants in Vitamin C provide H+ atoms so they can stabilise free radicals that damage cells by pairing up with free unpaired electron.

49
Q

How can salt increase CVD risk

A

Salt causes kidneys to retain water so there are higher fluid levels in blood leading to high BP

50
Q

How can alcohol increase risk

A

Can result in tissue damage like liver damage, if liver is damaged then glucose and lipid removal from blood is impaired.

51
Q

Describe diuretics (antihypertensive)

A

Increase urine vol, lowering blood vol/pressure therefore lowering BP.
Side effects: nausea/dizziness

52
Q

Beat blockers (antihypertensive)

A

Reduce frequency and power of heart contractions by blocking heart to hormones.
Side effects: increase chance of diabetes

53
Q

ACE inhibitors (antihypertensive)

A

Blocks conversion of angiotensin 1 to angiotensin 11 which cause atrial constriction, reducing BP.
Side effects: coughing/dizziness

54
Q

Use of warfarin as an anticoagulant

A

Interrupts vitamin K production so decrease risk of clot formation. Taking too much can lead to uncontrollable bleeding.

55
Q

Statins

A

Inhibit enzyme that produce LDL.
Side effects: tiredness/headaches

56
Q

Use of aspirin as a platelet inhibitory drug/anticogulants

A

Reduce platelet stickiness so lower chance of clots
Side effects: can cause stomach bleeding as aspirin disturbs stomach lining.

57
Q

Calcium channel blockers (antihypertensive)

A

Block calcium channels in muscle cells reducing muscle contraction and arteries diameter, so frequency/power of heart reduces.
Side effects: dizziness/headaches

58
Q

Type of diet to reduce risk of CVD

A

-energy balanced
-more unsaturated fats
-less salt
-less cholesterol

Biology Edexcel Alevel (8 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions