B1 rev

Question 1

What is the structure of water?

Answer 1

A molecule of water is one atom of oxygen joined to two atoms of hydrogen by shared electrons. Because the shared negative hydrogen electrons are pulled towards the oxygen atom, the other side of each hydrogen atom is left with a slight positive charge. The unshared negative electrons on the oxygen atom give it a slight negative charge. This makes water a dipole moecule.

Question 2

What is a mass transport system?

Answer 2

They are used to carry raw materials from specilaised exchange organs to the body cells, and to remove metabolic waste.

Question 3

What artery and vein found on the left hand side of the heart?

Answer 3

Aorta
pulmonary vein

Question 4

What artery and vein is found on the right hand side of the heart?

Answer 4

pulmonary artery
vena carva

Question 5

Where and which side of the heart is thicker?

Answer 5

Left ventricle is thicker

Question 6

What is the structure of arteries?

Answer 6

• carry blood from the heart to the rest of the body.
• thick walled, muscular and have elastic tissue in the walls to cope with high pressure
• inner linning (endothelium) is folded, allowing the artery to expand.

Question 7

How do you calculate heart rate?

Answer 7

60 divided by how long it takes to complete a cycle.

Question 8

Why are invertebrates used as more acceptable than vertebrates in an experiment?

Answer 8

they have a less sophisticated nervous system.

Question 9

How does a blood clot form?

Answer 9

A protein called thromboplastin is released from the damaged blood vessel. Thromboplastin, along with calcium ions from the plasma, triggers the conversion of prothrombin (a soluble protein) into thrombin (an enzyme). Thrombin then catalyses the conversion of fibrinogen ( a soluble protein) to fibrin (solid insoluble fibres). The fibrin fibres tangle together and form a mesh in which platelets (small fragemnts of cells in the blood) and red blood cells get trapped which forms a blood clot.

Question 10

What factors can increase the risk of cardiovascular disease?

Answer 10

Diet, high blood pressure, smoking, inactivity, genetics, age and gender.

Question 11

What are antihypertensives?
risks?

Answer 11

• reduces high blood pressure
• palpitations, abnormal heart rhythms, headaches and drowsiness.

Question 12

What are statins?
risks?

Answer 12

• reduce blood cholesterol
• muscle/ joint pain, digestive problems and an increased risk of diabetes. Nausea….

Question 13

What are anticoagulants?
risks?

Answer 13

• reduce formation of blood clots
• excessive bleeding, fainting