Biological molecules

What is amylose and how is it formed ?

~one of the polysaccharide from starch

~formed by alpha glucose molecules joined by a 1,4 glycosidic bond

-The angle causes the long chain to twit and form a helix structure ,the structure is further stabalised by hydrogen bonds

How are triglycerides form ?

• Consists of a glycerol molecule and three fatty acids

What functional group do fatty acids and glycerol have ?

• Glycerol:alcohol

• Fatty acids:carboxylic group (C=O)

What happens during esterification?

• The hydroxyl groups interact

• This leads the formation of three water molecules and and bonds between the fatty acids and the glycerol molecule=Ester bond

• The H atom on the glycerol and the OH on the fatty acid is removed

Due to lipids non-polar nature,what are the roles caused by this feature ?

-hormone feature

• Waterproofing

• Membrane formation. And the creation of hydrophobic barriers

• Electrical insulation

What are the roles of lipids ?

• Thermal insulation (To reduce heat loss )

• Cushioning (protect vital organs)

• Buoyancy

Define an unsaturated chain ?

• A carbon atom with one double bond

• Less hydrogen atoms

What is a monounsaturated fatty acid ?

• A fatty acids with just one double bond

What is a polyunsaturated fatty acid ?

• A fatty acid with two or more double bonds

What the properties of lipids with polyunsaturated?

• They are liquid at room temperature

• They are more healthier in a human diet because that can be broken down easier

What are the effects of the presence of a double bond on a fatty acids ?

• Te double bond causes them to bend or kick

• Disabling them from being able to pack closely together

What are lipids ?

• They consist of :

• Carbon

• Hydrogen

• Oxygen

• They are also known as macromolecules

Explain how the structure of cellulose is related to its function ?

-cell use is strong and insoluble

-Due to the Hydrogen bonds between cellulose molecules they form microfibrils .

-The microfibrils join together to form macrofibrils

-tThey both combine to form cell use fibres

What is amylopectin and how is it formed ?

-Polysaccharide

-formed by 1,4 glycosidic bonds

-some form 1,6 glycosidic bonds via a condensation reaction

-Has a branched structure

What is glycogen ?

-A polysaccharide

-glycogen forms more branches, which means its more compact

What are the properties of glycogen ?

-insoluble

-branched

-compact(good for storage )

What does the branching in Amylopectin enable ?

-Makes them compact

-Means that there are many free ends which enables glucose molecules to be added or removed from the chain

What is the definition of a monosaccharide ?

-a single unit of sugar

Define a polysaccharide ?

-when two or more monosaccharides are linked together

What is Glucose ?

-A monosaccharide

-Is a hexose monosaccharide

Why is glucose soluble in water. ?

-IT is a polar molecule

-So the hydroxyl group and water molecule form hydrogen bonds

What is a condensation reaction ?

-when two alpha molecules are side by side the two hydroxyl groups react to form form water

What happens in a condensation reaction between two alpha glucose molecules ?

-hydroxyll group react with each other

-2 hydrogen atoms and on oxygen atom ae removed to form water

-A bond forms between carbon 1 and carbon 4

-maltose the disaccharide is formed

Which two monosaccharides form sucrose ?

-fructose + glucose

Which two monosaccharides form lactose ?

-glucose + galactose

Which two monosaccharides form maltose ?

-Glucose +Glucose

What is ribose ?

-Pentose monosaccharide

Where is ribose present ?

-sugar present in RNA nucleotides

-deoxyribose the sugar present n the DNA nucleotides .

What reaction do plants undergo to release energy ?

-Hydrolysis

What is a Hydrolysis reaction ?

-the addition of a water molecule

-Th reaction is catalysed by an enzyme

How is cellulose formed ?

-beta glucose molecules reacts with an alternate glucose molecule which is flipped upside down 1,4 glycosidic bond

-A straight chain molecule is formed

How are microfibrils formed ?

-When cellulose molecules make hydrogen bonds with each other

How are macrofibrils formed ?

—when microfibrils join together

How do fibres form ?

-when macrofibrils combine

What are the properties of cellulose fibres ?

-insoluble

-strong

Give 3 examples of polysaccharides ?

-cellulose

-starch

-glycogen

Define a hydrogen bond?

-positive region and negative region interact with each other

What are the properties of hydrogen bonds ?

-have relatively weak interactions so they break and reform between the constantly moving water molecules

What are the characteristics of water ?

-High boiling point

-cohesive properties

-adhesive properties

-Is a transport medium

-water acts as a coolant

Why does water have a high boiling point ?

-It is a small molecule

-This is due to the hydrogen bonding between the water molecules ,so it requires a lot of energy to increase the temperature of water

Why is water less dense in its solids state ?

-When water freezes each water molecule needs to form 4 hydrogen bonds

-This requires distance

Why is water cohesive ?

-The molecules are attracted to each other (polar)

How does water exhibit capillary action ?

-Because of adhesion and cohesion which allows water to rise up a narrow tube against the force of gravity

Wha is water a good solvent ?

It is a polar molecule ,so the negative charge and positive charge are attracted other substances

Suggest ,with reasons which properties of water make it such a an important component in the blood ?

-water is a good solvent which means that substance such as nutrients can easily dissolve into the bloodstream .

-water has a high specific heat capacity,which allows the bloods temperature to remain constant,which allows chemical reactions occur and enzyme activity .

Explain why water is a polar molecule ?

-Because the oxygen atom has a small region of negative charge .

-The hydrogen atoms have a small region of positive charge

Define a glycosidic bond ?

-A covalent bond between glucose monomers

Define carbohydrate ?

-Molecules that only contain the elements carbon,hydrogen and oxygen

Why is amylopectin and glycogen structurally similar ?

-Both branched through 1,6 glycolic bonds