Lecture 3.1: Macromolelecules 2 Flashcards
What are carbohydrates?
-Carbon molecules with hydrogen groups and hydroxy groups
-They act as energy storage and transport molecules
-They also service carbon skeletons for other molecules
What are monosaccharides?
they are monomers of carbohydrates; simple sugars
What are disaccharides?
There are two monosaccharides linked by one covalent bond
What are oligosaccharides?
They are carbohydrates that have between three and 20 monosaccharides
What are polysaccharides?
We are carbohydrates composed of hundreds and hundreds of thousands of monosaccharides like starch, glycogen and cellulose
What is the general formula for carbohydrate monomer?
it is Cn(H2O)n maintaining a ratio of one carbon to two hydrogen to one oxygen
What happens to carbohydrates during polymerization?
It is a condensation reaction where water is removed, and therefore carbohydrate, polymers ratios differ somewhat from the 1:2:1 ratios of monomers.
What are some isomers of monosaccharides?
Triose, Tetros, Pentoses and Hexoses
What is the preferred energy source for cells?
Glucose
In which shapes does glucose exist in? Which is the most stable one?
It can exist in straight chain or ring form. However, the ring form is the most stable one.
What are the links between monosaccharides when they’re bounded together?
Glycosidic linkages. These can be an alpha or beta.
How many glycosidic linkages do disaccharides have?
They only have one.
Where are oligosaccharides usually found?
They are usually found covalently bonded to proteins and lipids.
What are some examples of polysaccharides?
Starch, glycogen, and cellulose.
Is fibre digestible for animals? If not, explain why.
No, fibre is not digestible for animals because they have the enzymes they can only hydrolyze alpha glycosidic links, but not the beta links.
How can carbohydrates be modified?
By the addition of functional groups
How are sugar phosphates created?
The are created when a phosphate is added to one or more hydroxy group
How are amino sugars created?
They are created when amino groups can be substitute for alcohol groups.
Are lipids soluble in water? Why not?
No, because the many non-polar covalent bonds of hydrogen and carbon in lipids, make them aggravate away from water, which is polar. Instead, they are attracted to each other via a weak, but additive, Vander walls forces.
Which is the only group of macromolecules that does not consist of polymers?
Lipids
What are lipids made up of then?
They are made up of smaller fatty molecules, such as “fatty” acids, and glycerol.
What are fats and oils chemically?
They are triglycerides. They have three fatty acid moles, and one glycerol molecule.
What is glycerol?
It is a three carbon molecule with three hydroxide groups.
What are fatty acids?
They are long chains of hydrocarbons with a carboxyl group at one end.
What are saturated fatty acids?
They have single carbon-to-carbon bonds, making them have rigid and straight structures. They are also solid at room temperature, which makes them fat.
What are unsaturated fatty acids?
They have at least one double bonded carbon in one of the chains and their chains are not completely saturated with hydrogen atoms. Their double bonds causes “kinks” that prevent easy packing. Therefore, they are liquid at room temperature and are concerned to be oils.
What are phospholipids?
They have two hydrophobic fatty acid tails and one hydrophilic phosphate, attach to the glycerol
How do phospholipids orient themselves in aqueous solutions?
They create bilayers with their heads facing outward and their tails facing in words because they want their phosphate groups to face the water and their tail to face away from it.
What makes phospholipids amphipathic ?
Because they have one hydrophilic end and one hydrophobic end.
What are Cartenoids & Chlorophylls?
They are light absorbing pigments found mostly in plants.
How is carotenoid-beta-carotene used in plants or animals?
In plants, it traps light for photosynthesis, and in animals, it can be broken into two molecules of vitamin A.
What do steroids do?
They signal molecules and hormones.
What are steroids made up of?
They consist of organic compounds with a series of fused rings.
Which is a common steroid of the animal cell membrane and what is its main purpose in humans?
This main steroid is cholesterol, and it serves as an initial substrate for synthesis of the hormones, testosterone and estrogen.
What are the fat soluble vitamins?
Vitamins A, D, E, and K
Which vitamins are water soluble?
Vitamins B and C.
What are waxes?
They are highly non-polar molecules, consisting of saturated, long fatty acids bonded to long fatty alcohols via and Esther linkage.
What is the purpose of waxy coatings in nature?
In nature, they help repel water and prevent water loss from structures, such as hair for feathers and leaves.
Which are the main two nucleic acids?
DNA and RNA.
What are the monomer for nucleic acids called?
They are called nucleotides.
What do nucleotides consist of?
A pentose sugar, a phosphate group and a nitrogen containing base.
What is the backbone of DNA and RNA?
It is phosphate groups bonded by phosphodiester linkages.
How many H-bonds can the A-T pair in DNA form?
2
How many H-bonds can the G-C pair in DNA form?
5
What are the bases for DNA?
They are adenine, cytosine, guanine, and thymine.
True or False. The two strands of DNA run in the same direction.
False, they run in opposite directions. They are anti-parallel.
The sequence of bases for DNA form a primary structure. However if two strands of DNA molecule come together, which structure do they form?
They form a secondary structure in the shape of a double helix.
What are the four bases for RNA?
they are adenine, cytosine, guanine and uracil.
What is the “replicator first” hypothesis?
It suggests that RNA must’ve come before DNA since DNA needs RNA to reproduce, but RNA can reproduce on its own.
Where is the information stored for DNA?
it is stored in the order of the four different bases.
Where does DNA send the order of their basis to next?
They send this order to RNA molecules, which then send the order to amino acids in proteins.
Which is the other species that have the closest DNA similarity to humans?
chimpanzees
