Class 1

Question 1

4 classes of biological molecules

Answer 1

proteins
nucleic acids
carbohydrates
lipids

Question 2

what are proteins

Answer 2

they are linear polymers of L-amino acids that are joined by peptide bonds

Question 3

how are peptide bonds formed

Answer 3

they are formed though condensation reactions
- when the carboxyl group of one molecule reacts with the amino group of the other molecule, releasing a molecule of water (H2O)

Question 4

what are the functions of protein

Answer 4

regulation
signaling
transport
catalysis
movement
structure

Question 5

what are nucleic acids

Answer 5

the information molecules in the cell
- monomers
- phosphate group + sugar + base called a nucleotide
-DNA & RNA are the two main ones

Question 6

what is DNA

Answer 6

double helix made up of 2 strands that are polymers of deoxyribonucleotides

Question 7

what holds DNA together, what bases connect

Answer 7

non-covalent interactions between bases
A –> T
G –> C

Question 8

What is RNA

Answer 8

single- stranded polymer of ribonucleotides contains bases A,G,C and U (replaces T)

Question 9

nucleic acids are polymer of nucleotides that are joined together by…?

Answer 9

phosphodiester bonds (catalyzed by DNA or RNA polymerase)

Question 10

central dogma of molecular biology

Answer 10

information flows from DNA to RNA to protein

Question 11

DNA –> DNA

Answer 11

replication

Question 12

DNA –> RNA

Answer 12

transcription by RNA polymerase

Question 13

RNA – > Protein

Answer 13

Translation

Question 14

Carbohydrates are..?

Answer 14

linear or branched polymers of monosaccharides

Question 15

4 monosaccharide characteristics

Answer 15

1) can be classified according to the number of cartoon atoms
2) Most sugars are in the cyclic form(ring form), not in the open-chain (acrylic form)
3)they are join together to form di, olio, and poly saccharides
-onyl mono and di are sugars
4) There are thousands of different carbohydrates, which can be linked together in chains and form branches via glycosidic bonds (Glycogen or Starch synthase)

Question 16

what makes up lactose

Answer 16

galactose + glucose

Question 17

what makes up sucrose

Answer 17

glucose + fructose

Question 18

maltose

Answer 18

glucose + glucose

Question 19

what are the polysaccarides

Answer 19

branched glycogen(from animal)
starch (plant sources)
unbranched cellulose(plant sources

Question 20

some functions of carbohydrates

Answer 20

fuel source, glucose stored as glycogen in animals
structural molecules(cellulose)
signaling ( cell-cell recognition)
lubricants

Question 21

what are lipids

Answer 21

water-insoluble molecules that are highly soluble in organic solvents

Question 22

fatty acids

Answer 22

simplest form of lipid
long hydrocarbon chain +carboxyl group
most commonly used as fuel

Question 23

triglycerols

Answer 23

storage form of fatty acids

Question 24

Fats

Answer 24

consist of glycerol and 3 fatty acids
created via 3 condensation reactions creating ester linkages that connect carboxyl groups to the hydroxyl groups in glycerol

Question 25

membran lipids

Answer 25

phospholipids

Question 26

glycolipids

Answer 26

bound to carbohydrates, membrane components

Question 27

steroids

Answer 27

cholesterol is a steroid -4 fused hydrocarbon rings with a steroid at on end and a hydroxyl group on the other, cell membrane and hormone

Question 28

emphatic nature of lipid

Answer 28

hydrophilic head - can dissolve in water hydrophobic tails - cannot dissolve in water

Question 29

emphatic nature of lipid

Answer 29

hydrophilic head - can dissolve in water hydrophobic tails - cannot dissolve in water

Question 30

6 functions of lipids

Answer 30

• Major component of membrane (phospholipids) • Long term energy storage • Protection against heat loss (insulation) • Protection against physical shock • Protection against water loss • Chemical messengers (hormones)

Question 31

covalent bonds

Answer 31

bonds in which the electrons are shared by the participating amino acids

Question 32

peptide bond enzyme?

Answer 32

each amino acid is attached to another amino acid by a covalent bond enzyme: peptidyltransferase

Question 33

phosphodiester bond enzyme?

Answer 33

a covalent bond in RNA and DNA that holds na polynucleotide chain together by joining a phosphate group at position 5 in the pentose sugar of one nucleotide to the hydroxyl group at position 3 in the pentose sugar of the next nucleotide enzyme: DNA or RNA polymerase

Question 34

ester bonds enzyme?

Answer 34

triglycerides are lipids inciting of one glycerol molecule bonded with three fatty acids molecules. The bonds between the molecules are covalent and are called ester bonds enzyme: actyltransferase

Question 35

glycosidic bond enzyme?

Answer 35

carbohydrates are made up of monosaccharides linked together into polysaccharide chains by a type of covalent bond known as a glycosidic bond enzyme: glycogen synthase

Question 36

4 main types of non covalent bonds

Answer 36

1) hydrogen bonds 2) ionic bonds, or electrostatic interactions 3) van der Waals interactions 4) hydrophobic bonds

Question 37

why is water dipolar and cohesive

Answer 37

1) water is dipolar because it has an uneven distribution of electrons between the hydrogen and oxygen - oxygen nucleus attracts e- stringer than hydrogen resulting in unequal share and dipoles 2) it forms hydrogen bonds with each other and other polar molecules and acts as a solvent 3) cohesive bc the hydrogen bonds make water very attractive to each other

Question 38

what is a hydrogen bond -its property?

Answer 38

a hydrogen bond is an attractive force between a partially positive charged hydrogen and a partially negative charged atom (oxygen or nitrogen) -hydrogen bonds between two molecules are disrupted by water when water forms hydrogen bonds with these molecules -the polarity of water and its ability to form hydrogen bonds renders it a solvent for any charged or polar molecule

Question 39

Is water polar or non polar

Answer 39

polar solvent (solvent of life): dissolves charged or polar compounds by replacing solute-solute H-bonds with solute-water H-bonds

Question 40

hydrophilic

Answer 40

Compounds that dissolve easily in water are hydrophilic (water soluble).

Question 41

hydrophobic

Answer 41

Non-polar molecules such as lipids are hydrophobic; side chains of some amino acids are referred to as “hydrophobic”. (water insoluble)

Question 42

amphipathic

Answer 42

molecules have polar or charged regions, as well as non-polar regions.

Question 43

ionic bonds/electrostatic interactions

Answer 43

a weak interaction between ions having opposite charges. water weakens these

Question 44

van der Waals interactions

Answer 44

the attraction between two molecules based on the transient electron asymmetry around an atom that induced a complimentary asymmetry in a nearby molecule - short range, molecules are neither polar nor charged, very weak

Question 45

hydrophobic interactions

Answer 45

the process in which non polar molecule in aqueous solutions are driven together because of the resulting increase in entropy of water molecules -powers membrane formation and protein folding