Topic 1

Question 1

Water - characteristics

Answer 1

• Polar molecule - dipole (H+, 0-) - hydrogen bonding holds water together - cohesive
• Good solvent - many chemicals dissolve easily into it - surrounds other molecules
• Thermal properties - high specific heat capacity - avoid rapid temp change

Question 2

Cardiac Cycle - process

Answer 2

Atrial Systole-
- atria fill - pressure means AV valves open
- blood leaks into ventricles
- atria walls contract, forcing blood into ventricles
Ventricular Systole
- ventricles contract - SLV open (+pressure)
- blood leaves through aorta and PA
- (AV valve closed - less pressure)
Diastole-
- atria and ventricles relaxed
- lower pressure
- SLV closes
- atria begin to fill again due to pressure in VC and PV

Question 3

Atherosclerosis - process

Answer 3

1. ENDOTHELIUM damaged
2. INFLAMMATORY responce - wbc move to area, accumulating cholesterol - ATHEROMA builds up
3. PLAQUE builds up (calcium, salts, fibrous tissue) - artery LESS ELASTIC
4. Blood pressure further increases due to positive feedback

Question 4

Blood clotting (THROMBOSIS) - process

Answer 4

1. PLATELETS stick to damaged wall
2. THROMBOPLASTIN released causes…
3. PROTHROMBIN (soluble protein) into THROMBIN (enzyme)
4. thrombin catalyses FIBRINOGEN (soluble protein) into FIBRIN (insoluble fibers)
5. Mesh of fibrin forms - trapping more platelets and RBCs

Question 5

Disaccharides

• Maltose
• Lactose
• Sucrose

Answer 5

MALTOSE
- glucose + glucose (1-4 glyc link)
- produced when amylase breaks down starch
LACTOSE
- glucose + galactose (1-4 glyc link)
- found in milk
SUCROSE
- glucose + fructose (1-2 glyc bond)
- usually transported in this form in plants

Question 6

Polysaccharides

- Starch

Answer 6

• amylose + amylopectin
• Amylose - straight chain - 1-4 glyc links
• Amylopectin - side branches- 1-6 glyc bonds
• storage of carbohydrates in plants
• not readibly soluble

Question 7

Polysaccharides

- Glycogen

Answer 7

• glucose molecules (1-6 and 1-4 glyc links)
• side branches - rapidly hydrolysed for energy
• bacteria and fungi main energy store

Question 8

Polysaccharides

- Cellulose

Answer 8

• glucose molecules
• straight chain
• used for strength in plants

Question 9

Unsaturated Fats

Answer 9

• double bonds - kink at each bond
• liquid at room temp - can’t lie close together - intermolecular forces weak between triglycerides
• make LDL’s
• Mono - help in the removal of LDL’s from blood
• Poly - + activity of LDL receptor sites

Question 10

Saturated Fats

Answer 10

• single bonds - no kinks
• solid at room temp - strong intermolecular forces
• mainly found in meat & dairy products
• make HDL’s

Question 11

Triglycerides

Answer 11

one glycerol molecule and three fatty acids

Question 12

Risk factors CVD

Answer 12

• Smoking
• Alcohol
• Inactivity
• Salt
• Stress

Question 13

Reducing risk

Answer 13

• Antihypertensives - lower blood pressure
• Statins - reduce cholesterol
• Beta blockers - decrease actions of hormones e.g. adrenaline
• Lifestyle change - diet/ exercise
• Anticoagulants - thin blood
• Platelet inhibitory drugs - reduces stickiness of platelets