Lecture 2

Question 1

What is most of the cell

Answer 1

Water

Question 2

How is the DNA arranged in the cell

Answer 2

Wrapped around histones

Question 3

What are the two types of chromatin

Answer 3

Euchromatin - Less condensed

Heterochromatin - Highly condensed

Question 4

How many bonds are there between AT and GC and what does this mean?

Answer 4

2 bonds between A and T and 3 bonds between G and C therefore, more energy is required to break GC than AT

Question 5

What are the five types of chemical bonds?

Answer 5

1. Hydrogen bonds - N, O or F attract H and between dipoles of water
2. Ionic interactions - Electrical attractions - Metal and Non metals
3. Covalent bonds - two NON metals
4. Van der Waals
5. Hydrophobic interactions

Question 6

What is special about covalent bonds

Answer 6

They have a precise 3D structure and are defined by bond angles and bond lengths

Question 7

What is special about C-C and C=C?

Answer 7

C-C allows rotation whereas C=C does not allow any rotation

Question 8

What is Novichok

Answer 8

Novichok inhibits acetylcholinesterase - Nervous inhibitor

Question 9

Whats the phrase about dissolving

Answer 9

Like dissolves like therefore water will dissolve polar molecules but will not dissolve non-polar molecules

Question 10

What are the main polymers found in cells

Answer 10

1. Polysaccharides
2. Fats/Lipids
3. Nucleic acids
4. Proteins - polymers of 20 different amino acids in specific sequences

Question 11

Sugars

1. What is the simplest form of a sugar
2. What is the formula for a sugar
3. What are three sugars
4. What are disaccharides?
5. What is the rhyme?
6. What is lactose made of?
7. What type of bonds are between polysaccharides?
8. What is glycogen made of?
9. What is an oligosaccharide?
10. What are the functions of a glycoprotein?

Answer 11

1. Monosaccharides
2. (CH20)n
3. Glucose, Mannose and Galactose (all isomers)
4. Simple polysaccharides
5. My Great Granny Sucks Fruit Gums
   Maltose = Glucose + Glucose
   Sucrose = Glucose + Fructose
6. Lactose = Glucose + Galactose
7. Glycosidic bonds
8. Glucose
9. Short chain polysaccharides
10. -Prevent blood cells sticking together
    - Cell communication
    - Cellular identity

Question 12

Fatty acids

1. What is palmitic acid?
2. Draw a fatty acid
3. How are fatty acids stores in the cytoplasm
4. What are the two types of fats?
5. Whats special about fatty acids?
6. What’s another lipid?
7. What are the four functions of membrane bound proteins

Answer 12

1. Amphipathic - both hydrophobic and hydrophilic
2. Carboxyl group at the head which behaves as an acid - hydrophilic and long hydrocarbon chain - hydrophobic
3. Triacylglycerol
4. Saturated - No double bonds, from meat and dairy
   Unsaturated - Double bonds, from plant based products
5. They can be metabolised to generate energy by entering at different points in aerobic respiration
6. Phospholipids
7. Transporters, Anchors, Receptors and Enzymes

Question 13

Nucleic acids

1. What are three functions of nucleotides?

Answer 13

1. • Carry chemical energy in the easily hydrolysed phosphoanhydride bonds
     - Combine with other groups to form coenzymes
     - Used as signalling molecules in the cell

Question 14

Amino acids / Proteins

1. What is the general formula for an amino acid and what does it exist as
2. What is a zwitterion
3. What are amino acids in acid
4. What are amino acids in neutral
5. What are amino acids in alkaline
6. What are proteins?
7. How are peptide bonds formed?
8. Give the four types and an explanation of protein structure
9. What happens when protein assembly goes wrong?

Answer 14

1. In notes and it exists as a zwitterion
2. A compound with no overall charge, but which contains separate parts which are positively and negatively charged
3. They are pronated which means its NH3 and COOH
4. Zwitterions
5. All depronated which means NH2 and COO-
6. Amino acid chains joined together by peptide bonds
7. Condensation reactions
8. 1) Primary - Amino acid sequence - Covalent bonds
   2) Secondary - Alpha helix and Beta pleated sheet - H bonds
   3) Tertiary - 3D structure - Hydrophobic bonds
   4) Quaternary - Multi protein complex
9. Cystic fibrosis - mutations in Cl- protein channel

Question 15

Aspartic acid

Answer 15

Asp - D - Negative

Question 16

Glutamic acid

Answer 16

Glu - E - Negative

Question 17

Arginine

Answer 17

Arg - R - Positive

Question 18

Lysine

Answer 18

Lys - K - Positive

Question 19

Histidine

Answer 19

His - H - Positive

Question 20

Asparagine

Answer 20

Asn - N - Uncharged polar

Question 21

Glutamine

Answer 21

Gln - Q - Uncharged polar

Question 22

Serine

Answer 22

Ser - S - Uncharged polar

Question 23

Threonine

Answer 23

Thr - T - Uncharged polar

Question 24

Tyrosine

Answer 24

Tyr - Y - Uncharged polar

Question 25

Alanine

Answer 25

Ala - A - Non polar

Question 26

Glycine

Answer 26

Gly - G - Non polar

Question 27

Valine

Answer 27

Val - V - Non polar

Question 28

Leucine

Answer 28

Leu - L - Non polar

Question 29

Isoleucine

Answer 29

Ile - I - Non polar

Question 30

Proline

Answer 30

Pro - P - Non polar

Question 31

Phenylalanine

Answer 31

Phe - F - Non polar

Question 32

Methionine

Answer 32

Met - M - Non polar

Question 33

Tryptophan

Answer 33

Trp - W - Non polar

Question 34

Cysteine

Answer 34

Cys - C - Non polar