Biology answer bank; Topic 1 (finished)
1. Mass transport occurs to overcome limitations of diffusion (SA:volume
ratio) in meeting the requirements of an organism
2. - Dipole nature allows ionic compounds to dissolve within it
- Cohesive and adhesive
- Liquid at room temperature
3. High specific heat capacity means
i. internal temperature changes slowly and less energy is
used on temperature control
ii. Thermally stable environment for aquatics
4. - Thick muscle and elastic tissue maintains a smooth pressure rate
- Narrow lumen maintains high pressure
- Endothelium reduces friction from blood
5. - Valves stop backflow of blood due to lower pressure
- Wide lumen
- Endothelium reduces friction from blood
6. - One cell thick walls allow fast gas diffusion
- Long length allows a large SA:Volume ratio
7. Atrial systole
a. Atria contract, the volume decrease increases pressure
b. AV valves open due to pressure in atria being higher than
ventricular pressure
c. Blood flows into ventricles
Ventricular systole
d. Ventricles contract, the volume decrease increases pressure
e. AV valves close due to pressure in ventricles being higher than
atrial pressure
f. SL valves open due to pressure in ventricles being higher than
aortic pressure
g. Blood flows into aorta
Diastole
h. Blood back flows within aorta
i. So SL valves close due to pressure in aorta being higher than
ventricular pressure
j. Elastic recoil in atria walls provides low pressure
, k. Blood is drawn into atria
8. Endothelial damage leads to an inflammatory response
a. White blood cells move into walls
b. Cholesterol accumulates
Atheroma becomes a plaque
a. Calcium salts build up
b. Fibrous tissue build up
Wall hardens
a. Arterial elasticity is lost
Narrowing of lumen causes a decrease in arterial volume
a. Causing higher blood pressure (+ve feedback loop)
9. - Damaged tissue releases thromboplastin
- Platelets, vitamin K and Ca stick to damaged wall forming a platelet
plug
- Cascade of chemical changes catalyse prothrombrin to thrombrin
- Thrombrin catalyses soluble fibrinogen to insoluble fibrin
- Fibrin mesh forms and traps red blood cells and platelets
- Causing a clot
10. Genetic mutations can cause
a. High blood pressure
b. High LDL levels in blood
11. High saturated fat
a. High LDL levels cause plaques
b. Results in high blood pressure
c. Damage to walls increase risk of atheroma/ clot formation
High salt
a. Kidneys retain more water
b. High fluid levels lead to high blood pressure
c. Damage to walls increase risk of atheroma/ clot formation
12. Reduced activity at old age leads to higher chance of obesity (and
higher blood pressure)
- Less elastic arteries (causing higher blood pressure)
13. Hormones
a. Oestrogen increases HDLs in blood
1. Mass transport occurs to overcome limitations of diffusion (SA:volume
ratio) in meeting the requirements of an organism
2. - Dipole nature allows ionic compounds to dissolve within it
- Cohesive and adhesive
- Liquid at room temperature
3. High specific heat capacity means
i. internal temperature changes slowly and less energy is
used on temperature control
ii. Thermally stable environment for aquatics
4. - Thick muscle and elastic tissue maintains a smooth pressure rate
- Narrow lumen maintains high pressure
- Endothelium reduces friction from blood
5. - Valves stop backflow of blood due to lower pressure
- Wide lumen
- Endothelium reduces friction from blood
6. - One cell thick walls allow fast gas diffusion
- Long length allows a large SA:Volume ratio
7. Atrial systole
a. Atria contract, the volume decrease increases pressure
b. AV valves open due to pressure in atria being higher than
ventricular pressure
c. Blood flows into ventricles
Ventricular systole
d. Ventricles contract, the volume decrease increases pressure
e. AV valves close due to pressure in ventricles being higher than
atrial pressure
f. SL valves open due to pressure in ventricles being higher than
aortic pressure
g. Blood flows into aorta
Diastole
h. Blood back flows within aorta
i. So SL valves close due to pressure in aorta being higher than
ventricular pressure
j. Elastic recoil in atria walls provides low pressure
, k. Blood is drawn into atria
8. Endothelial damage leads to an inflammatory response
a. White blood cells move into walls
b. Cholesterol accumulates
Atheroma becomes a plaque
a. Calcium salts build up
b. Fibrous tissue build up
Wall hardens
a. Arterial elasticity is lost
Narrowing of lumen causes a decrease in arterial volume
a. Causing higher blood pressure (+ve feedback loop)
9. - Damaged tissue releases thromboplastin
- Platelets, vitamin K and Ca stick to damaged wall forming a platelet
plug
- Cascade of chemical changes catalyse prothrombrin to thrombrin
- Thrombrin catalyses soluble fibrinogen to insoluble fibrin
- Fibrin mesh forms and traps red blood cells and platelets
- Causing a clot
10. Genetic mutations can cause
a. High blood pressure
b. High LDL levels in blood
11. High saturated fat
a. High LDL levels cause plaques
b. Results in high blood pressure
c. Damage to walls increase risk of atheroma/ clot formation
High salt
a. Kidneys retain more water
b. High fluid levels lead to high blood pressure
c. Damage to walls increase risk of atheroma/ clot formation
12. Reduced activity at old age leads to higher chance of obesity (and
higher blood pressure)
- Less elastic arteries (causing higher blood pressure)
13. Hormones
a. Oestrogen increases HDLs in blood
