carbohydrates Flashcards
Carbohydrates: elements, monomer, function
CHO, monosaccharides e.g. glucose, provides energy
The difference between monomers and polymers and macromolecules
Monomers are small, simple molecules produced by hydrolysis
Polymers are a large chain molecule made of similar monomers bonded together formed by condensation reactions
Macro molecules are large complex molecules with a large molecular mass they can be made of similar or different molecules bonded together e.g. lipids
explain Hydrolysis
A water molecule is used to hydrolyse the specific chemical bond in the two monomers which produces two separated monomers
Definition of hydrolysis
Breakdown with the addition of water
Condensation
A chemical Bonding between two molecules which produces a water molecule that is lost from the two molecules
Where can you find the glycosidic bond?
It is the covalent bond in carbohydrates between 2 monosaccharides
Examples of monosaccharides (one sugar)
Fruits, vegetables, honey, and nuts
Hexose(6 carbons) - glucose galactose fructose
Pentose(5 carbons) - deoxyribose ribose
Examples of disaccharides (two sugar molecules linked by glycosidic bond) milk & sugar
Sucrose = glucose + fructose
lactose = glactose + glucose
Maltose = glucose + glucose
Examples of polysaccharides (many sugar molecules linked) rice, potatoes, corn wheat
Starch made of alpha glucose
Glycogen made of alpha glucose
Cellulose made of beta glucose
Starch
- It is an energy storage molecule in plants, excess glucose from photosynthesis is stored as starch.
- It is relatively big so it’s insoluble in water so it doesn’t interfere with osmotic potential of cells.
- it contains a lot of chemical bonds which release lots of energy when broken
- is made up of two polysaccharides Amylose and amylopectin
What is the difference between amylose and amylopectin?
Amylose is a long coiled chain forming a helix of alpha glucose linked by 1,4 glycosidic linkage
Amylopectin is a long branched chain of alpha glucose linked by 1,4 glycosidic linkage then 1,6 every 24 units
Combined, they give the appearance of a tightly wound molecule
Glycogen
- Energy storage molecule in animal and fungi - excess glucose from digestion is stored as glycogen.
- Insoluble in water so doesn’t interfere with osmotic potential of cells.
- more branches means it’s compact so energy dense to meet high respiratory demand and other metabolic processes like movement and digestion of large organisms e.g. animals.
- More branches also means there are more sites where enzymes attach and can hydrolyse the glycosidic bonds to release energy faster
- Consist of highly branched chains of alpha glucose with 1,4 glycosidic bonds and 1,6 glycosidic bond every 10 units which release lots of energy when broken
Cellulose
- Structural molecule in plant cell wall.
- Insoluble in water so doesn’t interfere with osmotic potential of cell.
- Consists of long chains of beta glucose , alternate molecules of beta glucose are inverted and bonded by glycosidic bonds.
- Hydrogen bonds occur between separate straight chains of cellulose to form microfibrils that have high tensile strength.
What is the monomer?
A small simple molecule which is produced by hydrolysis of a polymer eg monosaccharide/ amino acids / nucleotides
What is polymer?
A large chain complex molecule made of similar monomers bonded together formed by condensation
Name the elements present in carbohydrates
Carbon hydrogen oxygen
(Cho) is wrong
What is the molecular formula of a triose
C3H6O3
Where is the Pentose sugar ribose found?
It is the sugar in RNA
Where is the Pentose sugar deoxyribose found
It is the sugar in DNA
Where is glucose found?
Throughout the body as a store and it is used for energy during respiration
Where is fructose found?
And fruit and sweet food
What are isomers?
Molecules with the same general formula but different structural formulas
What is the general formula of a disaccharide?
Cn(H2O)n-1
When the glycosidic bond is broken, which atoms would need to be replaced in order to produce complete monosaccharides?
O H2
What does the prefix glyco mean?
Sugar
How is fructose different from glucose? Although they are both hexose sugars?
Fructose has a five membered ring structure
Name the bonds within a microfibril of cellulose
Hydrogen between chains , 1,4 glycosidic between every other beta glucose inverted
What are the properties of cellular that make it perfect to be a plant cell wall
It’s insoluble
Has high tensile strength
Is flexible
Unreactive
Are polysaccharide soluble?
They are insoluble
Chitin (polysaccharide)
Beta glycosidic bonds
Contains N
Straight chains, no branching
Name two type of monomers found in biological molecules
Carbohydrates, amino acids
Name the number of carbon atoms in the disaccharide
12
How to test for reducing sugars
Add Benedict Regent to the sample and heat in a water bath at 100° for less than 5 mins,
A positive result goes from blue to yellow/red
Why is forming long beta glucose chains with hydrogen bonds between the chains useful for cellulose
It allows cellulose molecules to form strong fibres or microfibrils which provide structural support for the cell wall
What is the advantage and disadvantage of using amylose as a storage instead of amylopectin
It has a coiled structure so is more compact which allows more of it to be stored in a cell but it has no 1 to 6 bonds so it is broken down slower so the glucose is less readily available
Two ways in which molecular structure of cholesterol is similar to glucose
They both have hydrogens, carbons and oxygens
They both have hydroxyl groups
what is the physical property of glucose that allows it to be easily transported in the bloodstream
It is a monosaccharide so it’s small and its soluble in water so it can be carried by the blood
what’s the difference between alpha and beta glucose
The OH on the 1st C in beta is On top whereas in Alpha it’s below
What is the precise bond between the two glucoses to form a Maltose
1,4 glycosidic
