Lecture 1 & 2 Chemical components of the cell

Question 1

Polymers of Nucleotides:

Answer 1

DNA, RNA

Question 2

Polymer of Amimo acids:

Answer 2

Proteins

Question 3

Polymer of Fatty Acids:

Answer 3

Lipids

Question 4

Polymer of Sugars:

Answer 4

Polyssacharides

Question 5

Nucleotides are the building bloks for what?

Answer 5

DNA

Question 6

What are nucleotides composed of?

Answer 6

phosphate group, deoxyribose (5 carbon sugar), Nitrogen-containing base (adenine, thymine, guanine, cytosine)

Question 7

Deoxyribose sugar has what element missing?

Answer 7

Oxygen missing from the 2’ of sugar

Question 8

How are nucleotides bonded together?

Answer 8

covalently linked via a sugar phosphate backbone to form nucleotides (phosphodiester bonds), following from the 5’ phosphate to 3’ hydroxyl end

Question 9

How is DNA formed to make it double stranded?

Answer 9

antiparallel chains, stuctured by the sugar-phosphate backbone and held together by hydrogen bonding between complimentary base pairs

Question 10

Number of H bonds between A and T?

Answer 10

2

Question 11

Number of H bonds between G and C?

Answer 11

3

Question 12

What is the relation of the two antiparallel strands to one another? What does this allow?

Answer 12

Reverse compliments of eachother, which allows for DNA replication with one strand acting as a template to another

Question 13

What does DNA code for?

Answer 13

RNA

Question 14

Replication -> ………….. -> …………..

Answer 14

Replication -> Transcription -> Translation

Question 15

3 differences of RNA from DNA:

Answer 15

ribose replaces deoxyribose

uracil replaces thymine

RNA is single stranded

Question 16

4 types of RNA and functions:

Answer 16

mRNA - translated into proteins in rER

rRNA - structural rna which is important for making proteins from rna molecules

tRNA - delivers aa for translation

microRNA - regulates expression of other mRNA (targets mRNA to degrate or blok translation)

Question 17

mRNA is translated into proteins by what?

Answer 17

ribosomes

Question 18

In translation, how are the codes read?

Answer 18

In triples: codons

Question 19

What is the number of possible combinations for aa?

Answer 19

64

only 24 aa present - mulitiple codons code for same aa, stop codons, regulatory codons

Question 20

AA are the building bloks for what?

Answer 20

Proteins

Question 21

AA are composed of what?

Answer 21

H group

Carbonyl group

R group

Amino group

Question 22

How are aa bonded together?

Answer 22

condensation reactions in the ribosome (release of H₂O)

Peptide bond formed by the carbonyl and amino group

Question 23

How do AA vary from one another?

Answer 23

R groups

side chains affect the behaviour of the protein

Question 24

Non-polar side chains in AA - properties:

Answer 24

unreactive side chains (no H bonding)

hyrdrophobic side chains

Question 25

Non-polar side chains in AA - **alphabet:**

Answer 25

Gly, Ala, Val, Leu, Ile, Met, Phe, Trp, Pro

Question 26

Polar side chains in AA - **properties**

Answer 26

reactive side chains hydrophillic side chains accept/donate H bonds

Question 27

Polar side chains in AA - **alphabet:**

Answer 27

Ser, Thr, Cys, Tyr, Asn, Gln

Question 28

Charged side chains in AA - **properties:**

Answer 28

(theres postive and basic) Salt bridges H bonding Hydrophillic

Question 29

Charged side chains in AA - **alphabet:**

Answer 29

Negative/acidic: Asp, Glu Positive/basic: Lys, Arg, His

Question 30

**1^°**protein stucture:

Answer 30

the sequence of aa in a protein Mutation: sickle cell anemia (Glu6Val Hb), change in aa of the sequence E6V

Question 31

**2^°**protein stucture:

Answer 31

the local fold of a protein dependent on H bonds (stability) - alpha helix - beta sheet

Question 32

**3^°**protein stucture:

Answer 32

3D shape of a protein with the interactions between different domains/ side chains Interactions: - van der waals interactions - disulfide bridges - salt bridges - H bonding

Question 33

**4^°**protein stucture:

Answer 33

interations between two or more polypeptide chains to form a protein complex - collagen - haemoglobin

Question 34

What type of bonds are present in **fully saturated** fatty acids?

Answer 34

single bonds - palmitic acid - stearic acid

Question 35

What is the enzyme which transforms Stearic acid (saturated) to Oleic acid (unsaturated)?

Answer 35

desaturase - binds to one of the long ends of the fatty acid and removes H bonds from carbon to form double bond

Question 36

What is a monounsaturated acid?

Answer 36

one double bond (oleic acid)

Question 37

What does *cis* mean?

Answer 37

H on the same side

Question 38

What does *trans* mean?

Answer 38

H on oppostie sides

Question 39

What is a polyunsaturated acid?

Answer 39

many double bonds (linoleic acid - 2 double bonds = omega6) (alpha-linoleic acid - 3 double bonds = omega3)

Question 40

What is the effect on the fact that saturated and unsaturated fatty acids pack differently in membranes?

Answer 40

they change the fluidity and premeability

Question 41

Creation of mediators of inflammation, pain, fever, etc. with **Omega6**:

Answer 41

membrane phospholipids --(phospholipidase)--\> omega6 --(elongases desaturases)--\> archidonic acid --(cyclo-oxygenase 2, cox-2)--\> paracrines, leukotrienes, prostaglandins --\> mediators of inflammation, pain, fever, etc

Question 42

What are fatty acids primarily stored as?

Answer 42

Triglycerides

Question 43

What are triglycerides composed of?

Answer 43

3 glycerols bonded to fatty acids through ester bonds

Question 44

Comparison of energy storage in fat and glycogen:

Answer 44

more energy stored in fat takes longer to produce ATP from fat

Question 45

What type of molecule is glycogen?

Answer 45

Storing molecule for sugar and fatty acids

Question 46

Glycine

Answer 46

Gly, G

Question 47

Alanine

Answer 47

Ala, A

Question 48

Valine

Answer 48

Val, V

Question 49

Leucine

Answer 49

Leu, L

Question 50

Isoleucine

Answer 50

Ile, I

Question 51

Methionine

Answer 51

Met, M

Question 52

Trytophone

Answer 52

Trp, T

Question 53

Proline

Answer 53

Pro, P

Question 54

Serine

Answer 54

Ser, S

Question 55

Threonine

Answer 55

Thr, T

Question 56

Cysteine

Answer 56

Cys, C

Question 57

Tryosine

Answer 57

Tyr, Y

Question 58

Asparagine

Answer 58

Asn, N

Question 59

Glutamine

Answer 59

Gln, Q

Question 60

Aspartic

Answer 60

Asp, D

Question 61

Glutamic acid

Answer 61

Glu, E

Question 62

Lysine

Answer 62

Lys, K

Question 63

Arginine

Answer 63

Arg, R

Question 64

Histidine

Answer 64

His, H