Biological molecules

Question 1

What are the four main categories of biological molecules?

Answer 1

→carbohydrates
→proteins
→lipids
→nucleotides

Question 2

What is the general composition of a cell?

Answer 2

→water 70%
→macromolecules 26%
→small organic molecules 3%
→inorganic ions 1%

Question 3

What are the functions of carbohydrates?

Answer 3

→ an energy storage
→a fuel
→a metabolist
→a structural element

Question 4

What is the difference between D and L configuration in monosaccharides?

Answer 4

In the Fischer projection,
→if the OH on the chiral carbon furthest from the C=O group is pointed right it is D configuration
→ If it is pointed to the left it’s the L configuration.

Question 5

What is the difference between α and β glucose?

Answer 5

→ α the OH group on C1 is pointing downwards.

→ β the OH on C1 is pointing upwards

Question 6

What is the difference between glucopyranose and glucofuranose?

Answer 6

→In glucopyranose - 6 C atoms in the ring. →glucofuranose - 5 C atoms in the ring.

Question 7

What monosaccharides are sucrose and lactose made up of?

Answer 7

→SUCROSE: - α-D-glucose - β-D-fructose

→LACTOSE: - α-D-glucose - β-D-galactose

Question 8

What is the difference between the bonds in cellulose and starch/glycogen?

Answer 8

→ cellulose has β-1-4 glycosidic bonds between glucose monomers,

→starch/glycogen has α-1-4 glycosidic bonds between glucose monomers.

Question 9

Describe starch and glycogen

Answer 9

→Starch is made up of Amylose and Amylopectin.

→amylose : glucose is linked by 1-4 glycosidic bonds which make it unbranched.

→ amylopectin : glucose is linked by 1-4 and 1-6 glycosidic bonds, making it a branched chain.

→Glycogen is similar to amylopectin but with more frequent branching.

Question 10

list the 4 blood types with the antibodies and the antigens present on them

Answer 10

→GROUP A: Anti-B antibodies and A antigens

→GROUP B: Anti-A antibodies and B antigens

→Group AB: no antibodies and both A and B antigens

→Group O: both Anti-A and Anti-B antibodies and no antigens

Question 11

what are two examples of nucleotides that are important on their own?

Answer 11

→ATP - energy unit

→cAMP - second messenger

Question 12

what are two examples of amino acids that are important on their own?

Answer 12

→Tyrosine forms adrenaline, which triggers glycogen breakdown.

→ Histidine transforms into histamine - a vasodilator.

Question 13

What is the difference between cis and trans-unsaturated fatty acids?

Answer 13

→Trans has the H atoms on opposite sides around the double bond
→cis has them on the same side.

Question 14

Describe the structure of phospholipids

Answer 14

→ Phospholipids are made of up hydrophobic tails and hydrophilic heads.
→The heads are made up of glycerol,a phosphate group and choline.

Question 15

Describe cholesterol

Answer 15

→steroid that can intercalate into the membrane.
→the OH group interacts with the polar lipid heads
→ its steroid scaffold interacts with the fatty acids