C3 Biological molecules Flashcards
what does carbohydrates contain
Carbohydrates
carbon hydrogen and oxygen
A. a single unit sugar is called a
…
B. an example is
Carbohydrates
A. monosaccharide
B. glucose, fructose & ribose
A. when two monosaccarides join together it is called a …
B. an example is
Carbohydrates
A. disaccharide
B. lactose and sucrose
A. when two or more monosaccharides join together its called a…..
B. an example is
Carbohydrates
A. polysaccharide
B. glycogen, cellulose and starch
what is the chemical formula of glucose
Carbohydrates
C6H12O6
what is a hexose monosaccaride
Carbohydrates
a monosaccaride composed of six carbons
what is the structural difference between alpha and beta glucose
Carbohydrates
the carbon hydroxyl group on c1 is in opposite positions
why is glucose polar
Carbohydrates
due to the hyddrogen bonds that form between the hydroxyl groups and water molecules
what happens to 2 alpha glucose molecules when they interact
Carbohydrates
- the bonds are broken down and new ones are formed to form a new molecule
- two hydrogen atoms and a oxygen are removed from the monomers to from water
- a glycosidic bond forms between carbon 1 and 4
- this is a condensation reaction
what is formed when many alpha glucose molecules are joined together by glycosidic bonds
Carbohydrates
starch
what are the two polysaccharide in starch
Carbohydrates
- amylose
- amylopectin
describe amylose
Carbohydrates
- formed by alpha glucose molecules only joining by 1 and 4 glycocidic bonds
- angle of the bond means that the long chain twists to form a helix
- makes is compact and less soluble
describe amylopectin
Carbohydrates
- made between 1 and 4 glycosidic bonds and also some 1 and 6
- makes the structure branched
what is glycogen
Carbohydrates
- functionally equivilent srorage molecule
- highly branched - free ends where glucose molecules can be added or removed
- more compact
how can glucose be used for respiration
Carbohydrates
- starch undergoes hydrolysis reactions
- requires water
how can beta glucose join together and what does it result in
Carbohydrates
if alternate beta glucose molecules are turned upside down and forms a straight chain called cellulose
what is the chemical test for carbohydrates
Carbohydrates
benedicts
what is a reducing sugar and give an example
Carbohydrates
- a reducing sugar is a sugar which can donate electrons or reduce another molecule
- monosaccharides and some diasaccharides (maltose and lactose)
what is the proccess for benedicts test
Carbohydrates
- place sample in to boiling tube (must be liquid or grinded)
- add equal volume of benedicts
- heat gently in a water bath for 5 minutes
what is the result for reducing sugars
Carbohydrates
- react with copper ions
- blue to brick red pricipitate
what is the proccess for non reducing sugars
Carbohydrates
- after negative result
- boil sample with hydrochloric acid
- warm with benedicts in water bath for 5
why will a non reducing sugar give a positive result after being boiled in acid
Carbohydrates
because the sucrose has been hydrolysed to glucose and fructose
what is the test for starch
Carbohydrates
iodine
how do you carry out the starch test and what is the positive result
Carbohydrates
- add few drops of iodine dissolved in potassium iodide solution
- mix with sample
- yellow to black
what do lipids contain
lipids
carbon hydrogen and oxygen
why is lipids non polar
lipids
the bonds are more evenly distributed so there are no positive or negative areas
are lipids macro or micro molecules
lipids
macromolecule
what is a triglyceride
lipids
combination of one glycerol (alcohol) molecule and 3 fatty acids (carboxylic acid)