Macromlecules :carbohydrates, lipids Flashcards
What are carbohydrates made of?
Small sugar molecules -monosaccharides. A monosaccharide chain is called a polysaccharide.
What are the functional groups in a carbohydrate?
Hydroxyls and carbonyl. (meaning it is hydrophilic and therefore, carbohydrates are easily metabolised in our body)
What is the main role of carbohydrates in our body?
It is a short term source of energy.
In aqueous solutions, most pentoses and hexoses form rings, true or false?
True.
glucose + glucose = ?
glucose + fructose =?
glucose + glucose = maltose
glucose + fructose = sucrose
What is sucrose?
Sucrose is formed when one glucose and one fructose join together. Sucorse is the most abundant disaccharide and it provides an energy source for plants.
State 3 glucose polymers and contrast between them.
Starch, glycogen and cellulose.
- The oxygens in starch and glycogen are in an orientation of downward formation.
- Starch and glycogen are very similar and they are also easily metabolised. Cellulose however, acts as a fibre and is harder to metabolise.
- The oxygens in cellulose are in an up-down alternating formation. This allows cellulose to interact with other polysaccharide chains using hydrogen bonds.
- The structural difference b/w starch and glycogen is that glycogen starts forming branches.
The orientation of polysaccharides does not affect its chemical property. True or false?
False.
How do plants and animals respectively store glucose in them?
Plants store glucose as starch and animals store glucose as glycogen. Animals have enzymes to break down starch as glucose.
Where is glycogen stored in humans?
Liver and muscles.
What is the most abudant organic compund?
Cellulose.
How does cellulose give structural integrity to plant cell walls?
Parallel orientation of strands help form hydrogen bonds for structural integrity.
Why are pandas stupid?
A panda’s diet is ~90% composed of bamboo shoots, in which the major component (~50-70%) in cellulose
Pandas have not (yet) evolved the ability to digest cellulose and still retain a carnivore digestive tract.
Why can herbivores digest cellulose?
Certain herbivore animals (including cows and termites) and decomposing fungi have the enzymes (cellulase) to hydrolyze cellulose.
Where can chitin be found?
Insect exoskeletons and fungi cell walls.