3.1.2 Carbohydrates Flashcards
(28 cards)
How many monomers does glucose have , name them and draw them ?
2 , Alpha and Beta glucose
How are polysaccharides formed ?
Polysaccharides are formed by the condensation of many glucose
units.
How are glycogen and starch formed ?
Glycogen and starch are formed by the condensation of
α-glucose.
How is cellulose formed ?
Cellulose is formed by the condensation of β-glucose
What three monosaccharides do you need to know the structure of ?
Glucose , Fructose and Galactose
How do disaccharides form ?
Two monosaccharides are joined together by a
glycosidic bond. This is a condensation reaction which involves the removal of a
molecule of water
What is a polysaccharide ?
A long chain of monosaccharides that are linked by glycosidic bonds are known as a
polysaccharide
How is sucrose made ?
Glucose and Fructose
What is the stucture and fucntion of cellulose ?
Cellulose is a polymer of β glucose - it’s made of long, unbranched chains of
beta-glucose.
‒ Condensation reactions link carbon atom 1 to carbon atom 4 on the next β
glucose.
‒ The glucose subunits in the chain are oriented alternately upwards and
downwards.
‒ The consequence of this is that the cellulose molecule is a straight chain rather
than curved.
The cellulose chains are linked together by hydrogen bonds to form strong fibres
called cellulose microfibrils.
‒ Because of those fibres, the tensile strength of cellulose provides structural
support for the cells (e.g the cell walls) and prevents plant cells from bursting -
even under very high (water) pressure.
How is lactose made ?
glucose and galactose
How is Maltose made ?
Glucose and glucose
Where is starch found and what is it used for ?
Cells get their energy from glucose. Plants store excess glucose as starch.
‒ When a plant needs more glucose for energy, it will break down that starch to
release the glucose
What are the two versions of starch ?
Amylose and Amylopectin
What type of glucose is starch made of ?
Alpha glucose two variations amylose and amylopectin
What is the struture and function of amylose ?
Amylose is a long, unbranched chain of α-glucose. The angle of the glycosidic
bonds give it a coiled, cylinder-like structure. This compact structure is good for
storage because more glucose can be stored in a small space
What is the structure and function of amylopectin ?
Amylopectin is a long, branched chain of α-glucose. It has side branches which
allow the enzymes that break the molecule down to access glycosidic bonds
easily - meaning the glucose can be released quickly
Why is starch good for energy storage ?
starch is insoluble, water cannot enter the cells by osmosis - which makes it
very good for storage.
What number on carbons are the condensation links on ?
Condensation reactions link carbon atom 1 to carbon atom 4 on the next
α-glucose.
Where is glycogen found and what is the main function of it ?
Glycogen is the main energy storage material in animals
Where is glycogen stored in humans ?
it is stored in the liver and some muscles
Where is glycogen used ?
It’s used in cells where large stores of dissolved glucose would cause osmotic problems
What is the stucture of glycogen like ?
Glycogen has a similar structure to amylopectin but it has a lot more side
branches. These extra branches mean the stored glucose can be released very
quickly - something that is very important in animals.
What are the adaptations that make glycogen a suitable energy source ?
As a result of the branches, glycogen is very compact which makes it very good
for energy storage.
‒ Glycogen does not affect the osmotic balance of cells - i.e. cause too much water
to enter them.
What are reducing sugars ?
All monosachharides and some disaccharides including maltose and lactose
