Lecture 2 - Biomolecules

Question 1

What are carbohydrates?

Answer 1

• organic molecules

- Carbon, Hydrogen, Oxygen

Question 2

What is the formula of a carbohydrate?

Answer 2

CnH2nOn

Question 3

What does the suffix -ose mean?

Answer 3

sugar molecule

Question 4

What are the 3 structural isomers of carbohydrates?

Answer 4

glucose, galactose, & fructose

Question 5

How are disaccharides joined together?

Answer 5

Covalently

Question 6

glucose + fructose =

Answer 6

sucrose

Question 7

glucose + galactose =

Answer 7

lactose

Question 8

2 glucose molecules =

Answer 8

maltose

Question 9

What are two examples of a polysaccharide?

Answer 9

Starch & Glycogen

Question 10

Cellulose has what type of glycosidic bond?

Answer 10

Linear

Beta-1,4 glycosidic bonds

Question 11

Starch has what type of glycosidic bonds?

Answer 11

lightly branched
amylose (alpha-1,4 glycosidic bond)
amylopectin (alpha-1,4 & alpha-1,6 glycosidic bonds)

Question 12

Glycogen has what type of glycosidic bonds?

Answer 12

alpha-1,4 & 1,6 glycosidic bonds

Question 13

What are some examples of disaccharides?

Answer 13

sucrose, lactose, maltose

Question 14

What are some examples of monosaccharides?

Answer 14

Glucose, fructose, galactose

Question 15

T or F: During fasting or long-lasting exercise, the liver cannot add glucose to the blood through hydrolysis of its stored glycogen.

Answer 15

False

Question 16

Lipids: The longer the chain and fewer double bonds mean what for solubility?

Answer 16

Lower solubility in water

Question 17

What are Triglycerides composed of?

Answer 17

1 glycerol + 3 fatty acids

- Unsat. & Sat. fatty acids

Question 18

Why do we use triacylglycerols for stored fuels instead of polysaccharides?

Answer 18

1. Lipids has 2x more energy

2. Triacylglycerols are hydrophobic vs polysaccharides that has 2g of water per gram (extra weight)

Question 19

What percentage should be limit saturated & trans fats?

Answer 19

Saturated fat: 7%

Trans fat: 1%

Question 20

Trans fats raise and lower what?

Answer 20

Raise LDL (bad cholesterol) & triacylglycerol levels and lowers HDL (good cholesterol)

Question 21

LDL is what type of cholesterol

Answer 21

bad cholesterol

Question 22

HDL is what type of cholesterol?

Answer 22

Good cholesterol

Question 23

What are ketone bodies?

Answer 23

4 carbon acidic molecules (acetoacetic acid & beta-hydroxybutyric acid) and acetone (formed by release of CO2 from acetoacetic acid)

Question 24

Lipid into ketone bodies occurs when …

Answer 24

there’s a rapid breakdown of fat from a strict low carb diet (starvation) & uncontrolled diabetes (causes ketoacidosis)

Question 25

What are major components of the cell membrane?

Answer 25

Phospholipids

Question 26

What does a Glycerophospholipid consist of?

Answer 26

glycerol, 2 fatty acids, phosphate group & other molecules (like alcohol)

Question 27

What do Sphingolipids consist of?

Answer 27

- Fatty acid + phosphate group + Choline | - Fatty acid + Mono or oligosaccharide

Question 28

What are PAFs?

Answer 28

Platelet activating factor | - lipid mediator of inflammation

Question 29

What is the precursor for the steroidal molecules in our body?

Answer 29

Cholesterol

Question 30

Cholesterol serves as an precursor for what?

Answer 30

bile salts & vitamin D3

Question 31

Biosynthetic Pathway of Steroids: Cholesterol turns into Pregnenolone by what?

Answer 31

Cytochrome P450scc

Question 32

What are Eicosanoids?

Answer 32

Paracrine hormones, involved in inflammation, fever, & pain associated with injury or disease

Question 33

What is an Arachidonic Acid?

Answer 33

20-carbon polyunsaturated fatty acid

Question 34

Cox-1 is constitutive or inducible?

Answer 34

constitutive

Question 35

Cox-2 is constitutive or inducible?

Answer 35

Inducible

Question 36

Cox-1 involves what reactions?

Answer 36

Gastric protection & platelet function

Question 37

Cox-2 involves what reactions?

Answer 37

Pain, bone formation, & fever

Question 38

What are the regulatory functions of prostaglandins?

Answer 38

- regulation of blood vessel diameter - ovulation - uterine contraction during labor - inflammation reactions - blood clotting

Question 39

What is Thyrotropin?

Answer 39

Releasing hormone that is 3 AAs long

Question 40

What is the primary protein structure?

Answer 40

basic sequence of AAs

Question 41

What is the secondary protein structure?

Answer 41

alpha helix or beta pleated sheet formed as a result of H-bonds between the H of an amino group and the O of a nearby AA

Question 42

What is tertiary protein structure?

Answer 42

3D structure formed as a result of ionic bonds, H-bonds, or VDW between R groups of nearby AAs - polypeptide chains bend & fold

Question 43

What is quaternary protein structure?

Answer 43

multiple polypeptide chains covalently bounded together

Question 44

What are some functions of a protein?

Answer 44

- Structure of different tissues (collagen & keratin) - Enzymes - Antibodies - Synthesizing & repairing DNA - Transporting materials across the cell - Receiving & sending chemical signals - Responding to stimuli

Question 45

What are some examples of conjugated proteins?

Answer 45

Glycoproteins & Lipoproteins

Question 46

What are Glycoproteins conjugated with?

Answer 46

Carbohydrates (certain hormones & proteins in the cell membrane)

Question 47

What are Lipoproteins conjugated with?

Answer 47

Lipids (cell membranes & in the plasma)

Question 48

What are some proteins that are conjugated with pigment molecules?

Answer 48

Hemoglobin & Cytochromes (uses oxygen for energy production)

Question 49

What are two examples of FDA-approved PCSK9 inhibitors?

Answer 49

alirocumab (Praluent) & evolocumab (Repatha)

Question 50

Clinical Aspect: LDL & PCSK9

Answer 50

- LDL receptors remove LDL from the bloodstream - PCSK9 binds & destroys the LDLR with the LDL particle. - If PCSK9 is inhibited, the receptor returns to the surface of the cell and remove more cholesterol

Question 51

Nucleotides are bounded together by what synthesis?

Answer 51

Bonded together in dehydration synthesis rxns to form polynucleotide chains

Question 52

What are nucleotides composed of?

Answer 52

5-carbon pentose sugar, phosphate group, & nitrogenous base (pyrimidines/purines)

Question 53

What is the basis for the genetic code and is the largest molecule in the cell?

Answer 53

DNA

Question 54

What type of sugar does DNA have?

Answer 54

deoxyribose sugar

Question 55

What are the base pairings for DNA? (Law of complementary base pairing)

Answer 55

Adenine -> Thymine (2 H-bonds) | Guanine -> Cytosine (3 H-bonds)

Question 56

What type of bond allows the base to produce a double-stranded DNA molecule?

Answer 56

H-bonding

Question 57

What type of sugar does RNA have?

Answer 57

ribose sugar

Question 58

What are the base pairings in RNA?

Answer 58

adenine -> URACIL

Question 59

RNA is composed of what kinds of strand?

Answer 59

Single stranded

Question 60

What are the 3 major type of RNA molecules in the cytoplasm of cells?

Answer 60

mRNA, rRNA, tRNA

Question 61

T or F: All 3 types of RNA are made within the cell nucleus by using info. contained in DNA as a guide.

Answer 61

True

Question 62

What other roles do purine-containing nucleotides have?

Answer 62

- roles as energy carriers (ATP & GTP) - regulation of cellular events (cAMP) - coenzymes (NAD & FAD)