Biological Molecules

Question 1

What properties of water allows it to be a good solvent

Answer 1

• It’s a polar molecule which means it can dissolve other polar molecules and ions

Question 2

What properties of water allows it to be a good solvent

Answer 2

• It’s a polar molecule which means it can dissolve other polar molecules and ions

Question 3

What are the three properties of water

Answer 3

• Cohesion and surface tension
• High specific heat capacity
• Solvent properties

Question 4

What does it mean by cohesion in water

Answer 4

• Cohesion is a property of water that allows it to stick together.
• This is due to water being polar and having strong hydrogen bonds
• It allows water to form droplets and flow intead of separating.

Question 5

What is cohesion

Answer 5

Attraction between the same molecule

Question 6

How does cohesion cause surface tension

Answer 6

• Water molecules have strong cohesion
• Cohesion allows the molecules to flow and transport
• Cohesion produces surface tension when the water meets air

Question 7

What is a monosaccharide

Answer 7

• Simplest of sugars
• They are the monomers from which larger carbohydrates are made from.
• Glucose, Galactose and fructose are common monosaccharides

Question 8

What are disaccharides and how are they made

Answer 8

• They are made from 2 monosaccharides
• The reaction which forms it is called a condensation reaction
• The bond formed is a Glycosidic bonds

Question 9

Two isomers of Glucose

Answer 9

• Alpha and Beta glucose
  In Alpha OH are both at the bottom and in Beta OH are diagonal from each other.

Question 10

What 2 molecules are formed by the condensation reaction of Alpha glucose

Answer 10

• Starch
• Glycogen

Question 11

Explain the structure of starch

Answer 11

• Made from Amylose and Amylopectin
• Amylose is made by a linear polysaccharide chain joined by (1,4) glycosidic linkage . It has helical structure.
• Amylopectin is made by a branched polysaccharide chain by (1,4) and (1,6) glycosidic linkage.It is insoluble in water.

Question 12

Structure of monosaccharides

Answer 12

• If the sugar has an aldehyde group (the functional group with the structure R-CHO), it is known as an aldose. - If it has a ketone group (the functional group with the structure RC(=O)R′), it is known as a ketose.
• Depending on the number of carbons in the sugar, they also may be known as trioses (three carbons), pentoses (five carbons), and or hexoses (six carbons).

Question 13

Structure of Disaccharides

Answer 13

Glycosidic bonds (also called glycosidic linkages) can be of the alpha or the beta type.
- An alpha bond is formed when the OH group on the carbon-1 of the first glucose is below the ring plane.
- A beta bond is formed when the OH group on the carbon-1 is above the ring plane.

Question 14

Describe the structure of glycogen and explain why it is a suitable molecule to store energy.

Answer 14

Glycogen is a branched polymer of glucose that is stored in the liver and muscles of animals. The branching occurs through alpha-1,6-glycosidic bonds, which link together linear chains of glucose molecules that are themselves linked through alpha-1,4-glycosidic bonds.The highly branched structure of glycogen makes it a suitable molecule to store energy because it allows for rapid hydraulisis. The branching of the glycogen molecule means that there are many ends to the chains, allowing for many glucose molecules to be released at once. This is important for providing a rapid source of energy during times of high demand.The compact structure of glycogen means that it can be stored in large amounts within the liver and muscles without taking up too much space. This allows animals to store a significant amount of energy in a small space, which is important for survival during times when food may be scarce. Overall, the highly branched and compact structure of glycogen makes it an efficient and effective molecule for storing and rapidly accessing energy when needed.