Edexcel IAL Biology Unit 1 Topic 1

Risks of Platelet inhibitory drugs

- Nausea - Excessive bleeding - Diarrohea

Social and Ethical issues of Genetic screening

- Risk of miscarriage - false results can provide incorrect information - Unethical to abort a fetus if it has a genetic disorder

Distinguish between structure of saturated fatty acid and unsaturated fatty acid

- saturated fatty acid has no carbon - carbon double bonds whereas an unsaturated fatty acid has at least one carboncarbon double bond - saturated fatty acid chains are straight unsaturated fatty acid chains are not straight -ratio of H:C is higher in saturated fatty acids than unsaturated fatty acids ;

Fatty acids

1 Glycerol + 3 fatty acids

Amylopectin

1,6 and 1,4 glycosidic bonds, has side branches

Risks of Antihypertives

1. Abnormal heart rhythms 2. Fainting 3. Headaches 3. Blood pressure becoming too low

Examples of Polysaccharides

1. Amylose 2. Glycogen 3. Amylopectin

Examples of Antihypertives

1. Beta blockers 2. Diuretics 3. Vasodilators

Suggest how cholesterol affects membrane fluidity

1. Cholesterol binds to fatty acid tails of phospholipids 2. Pulling fatty acid tails together, which reduces movement of the phospholipids

Blood clotting

1. Damage to blood vessels exposes collagen fibers 2. Platelets are activated by the collagen fibers and change their shape, causing them to stick to the damaged wall temporarily. 3. Platelets release a protein Thromboplastin 4. Thromboplastin, activates a series of enzymes that... in the presence of Calcium ions and Vitamin K, convert the protein Prothrombin into the enzyme Thrombin 5. Thrombin catalyses the conversion of soluble fibrinogen into souluble fibrin 6. When many fibrin molecues stick together, a mesh is formed, which traps other platelets and red blood cells.

Athleresclorosis

1. Damage to endothelium by an irritant 2. Inflammatory response occurs White blood cells/Macrophages move to the site of infection causing atheroma formation 3. Calcium salts and fibrous tisue builds up at the site, forming a hard plaque on the inner wall of the artery

Examples of Monosaccarides

1. Glucose 2. Fructose 3. Galactose

Structure of Amylose

1. Long, coiled but unbranched chain with 1,4 glycosidic bonds

Examples of Disaccharides

1. Maltose 2. Lactose 3. Sucrose

Risks of using Statins

1. Muscle and joint pain 2. Nosebleeds 3. Digestive problems

Distinguish between the structure of a unsaturated and a saturated fatty acid

1. Saturated fatty acids have no carbon-carbon double bonds, whereas unsaturated fatty acids have at least one carbon-carbon double bond 2. Saturated fatty acid chains are straight, whereas unsaturated fatty acid chains are not straight

Factors affecting diffusion

1. Surface area to volume ratio 2. Concentration gradient 3. Temperature

What is the result of Athleresclorosis?

1. The artery loses some elasticity 2. Artery becomes narrower, which makes it more difficult to pump blood around the body 3. High blood pressure

Explain how a gene mutation affects gas exchange in a person with CF

1. defective CFTR protein 2. chloride ions are not transported out of the cells / sodium ions move into cells ; 3. water does not move out (of cells) / water moves in to cells 4. mucus (on cell surface) { is not diluted / is thicker / is more sticky } / eq ; 5. reduced rate of gas diffusion / reducing ventilation of alveoli

Explain why the human heart is divided into a left side and a right side

1. idea that it keeps oxygenated and deoxygenated blood separate ; 2. keeps { concentration / diffusion } gradient steep 3. idea that this results in sufficient oxygen being carried to the {tissues / cells / eq } and CO2 removed from tissues

Explain why different fatty acids have different melting temperatures

1. idea that the greater the number of double bonds the lower the melting temperature ; 2. (because) the fatty acid chain is more { bent / less linear ACCEPT double bonds result in kinks 3. fatty acids do not pack closely together; 4. weaker intermolecular forces covalent bonds or carbon bonds or pi bonds 5. less energy needed to separate fatty acid chain molecules

Explain how the structure of an artery is related to its function

1. smooth (endothelium) lining to reduce friction (between wall and blood) 2. (thick) elastic wall to allow stretch and recoil 3. collagen layer to provide strength / withstand high blood pressure 4. (smooth) muscle in wall to enable artery to change its diameter

Why does Atheresclorosis only occur in Arteries?

Arteries contain fast flowing blood under very high pressure, therefore there's high chance of damage to the artery wall

Polysaccharides

Containing three or more sugar units

Sucrose is made up of...

Fructose + Glucose = 1,2 glycosidic bond

Lactose is made up of...

Galactose + B glucose = 1.4 glycosidic bond

Structure of Amylopectin

Long, branched chain, with 1,4 and 1,6 glycosidic bonds

Glycogen

Made of many monomers of alpha glucose, with 1,4 and 1,6 bonds Many side branches

Structure Starch

Made up of Amylose & Amylopectin

Thromboplastin is a...

Protein

Function of Anticoagulants

Reduce blood clot formation

Function of platelet inhibitory drug...

Reduce formation of blood clots

Antihypertives function

Reduce/lower high blood pressure

Relative risk

The chance of an event occuring, in one group compared to the other group

Why does Atheresclorosis not occur in veins?

There's much lower pressure in veins, compared to arteries, so less risk of damage

Function of Statins

To reduce LDL cholesterol levels in the blood

Disaccharides

Two sugar units

Examples of Anticoagulants

Warfarin & Heparin

Thrombin is an...

active Enzyme

Maltose is made up of...

alpha Glucose + alpha Glucose = 1,4 glycosidic bond

Prothrombin is a...

inactive enzyme

Fibrin is...

insoluble

Amylose

lots of alpha glucose molecules joined together by 1,4 glycosidic bonds

Monosaccharide

single sugar unit

Fibrinogen is...

soluble