Lecture 2- Biomolecules

Question 1

what are the properties of ions and molecules that are essential for life? (4)

Answer 1

carbohydrates
nucleotides, nucleosides and nucleic acids
lipids
proteins

Question 2

what is an organic molecule?

Answer 2

a molecule that contains carbon

Question 3

what is a biomolecule?

Answer 3

organic molecule that is commonly associated with life (carbohydrates, nucleic acids, lipids, proteins)

Question 4

what is the general formula for carbohydrates?

Answer 4

CnH2n0n

Question 5

what are examples of carbohydrates?

Answer 5

glucose C6H12O6
ribose C5H10O5
cellulose
chitin

Question 6

what are 3 characteristics of carbohydrates?

Answer 6

most are hydrophilic
very abundant in nature
used for structure and energy

Question 7

what biomolecule can be added to a molecule to modify it?

Answer 7

carbohydrates

Question 8

how many carbons do glucose have?

Answer 8

6

Question 9

how many carbons does ribose have?

Answer 9

5

Question 10

how does the different number of carbons alter the molecule?

Answer 10

the number of structural monomers increases rapidly with the increase in carbons

Question 11

are carbohydrates monomers or polymers?

Answer 11

Carbohydrates are a biological polymer made of monomers called monosaccharides

Question 12

why are monosaccharides considered to be simple sugars?

Answer 12

because they are the building blocks for large complex carbohydrates or sugars

Question 13

why are we interested in nucleotides/ nucleosides?

Answer 13

because of their involvement in energy metabolism and signaling

Question 14

what does a nucleotide contain?

Answer 14

one or more phosphate groups
5- carbon sugar
carbon- nitrogen ring structure (nitrogenous base/ nucleobase)

Question 15

what is DNA made up of?

Answer 15

nitrogenous bases

Question 16

what are the 5 nitrogenous bases?

Answer 16

adenine
cytosine
guanine
thymine
uracil

Question 17

how is the nitrogenous base determined?

Answer 17

based on the structure

Question 18

what are examples of nucleotides?

Answer 18

adenosine
adenosine triphosphate
cyclic AMP
guanosine triphosphate
cyclic GMP

Question 19

what is adenosine?

Answer 19

a neurotransmitter

Question 20

what is adenosine triphosphate?

Answer 20

(ATP) basic molecule of energy storage in most organisms

Question 21

what is the function of cyclic AMP and cyclic GMP?

Answer 21

important signaling molecule within cells

Question 22

what is the function of guanosine triphosphate?

Answer 22

energy source in many physiological chemical reactions

Question 23

are lipids hydrophilic or hydrophobic?

Answer 23

hydrophobic molecules

Question 24

what do lipids contain?

Answer 24

mostly carbon and hydrogen
few oxygen
nitrogen
phosphorus

Question 25

what are examples of lipids? (5)

Answer 25

fatty acids glycerides phospholipids and sphingolipids steroids oxylipins

Question 26

what are the 3 roles of lipids?

Answer 26

structure of cells energy source communication (within cells and between cells)

Question 27

what is meant by lipids having a role in structure of cells?

Answer 27

lipids are in cell membrane (phospholipids) and membrane bound organelles

Question 28

why is it good that lipids are hydrophobic?

Answer 28

waterproof and thus keeps insides in and outsides out

Question 29

what do fatty acids consist of?

Answer 29

long unbranched hydrocarbon chain (8-28 carbons) has carboxyl functional group (ACIDIC)

Question 30

what is the difference between saturated fatty acids and unsaturated fatty acids?

Answer 30

saturated fatty acids have no double bonds and form a straight chain unsaturated fatty acids have double bonds and have a kink

Question 31

what does it mean if a fatty acid has more double bonds

Answer 31

its unsaturated and is less likely to be a solid at room temperature (it will remain an oil)

Question 32

what does a glyceride consist of?

Answer 32

fatty acid + glycerol (3 carbons)

Question 33

when a fatty acid and a glycerol make glyceride what happens?

Answer 33

looses a water (H2O) molecule

Question 34

what is the difference between a monoglyceride, diglyceride and triglyceride?

Answer 34

monoglyceride: glycerol + 1 fatty acid diglyceride: glycerol + 2 fatty acids triglyceride: glycerol + 3 fatty acids

Question 35

what does a phospholipid consist of?

Answer 35

diglyceride (glycerol + 2 fatty acids) phosphate variable "R" group

Question 36

is the variable "R" group in a phospholipid polar or non-polar?

Answer 36

polar group

Question 37

phospholipids are amphipathic, what does that mean?

Answer 37

hydrophilic and hydrophobic hydrophilic head hydrophobic tail

Question 38

is hydrophilic polar or nonpolar?

Answer 38

polar

Question 39

is hydrophobic polar or nonpolar?

Answer 39

nonpolar

Question 40

what are the 3 arrangements of phospholipids?

Answer 40

phospholipid bilayer micelles aqueous center (lecture 2, slide 22)

Question 41

what is the difference between a phospholipid and a sphingolipid?

Answer 41

sphingolipids have sphingosine phospholipids have glycerol (other than that this is the only difference)

Question 42

what is the difference between a phospholipid and a glycolipid/ glycophospholipid?

Answer 42

glycolipids have a carbohydrate attached to the "R" group phospholipids dont have a carbohydrate

Question 43

what does a glycosphingolipid consist of?

Answer 43

fatty acid sphingosine carbohydrate

Question 44

what is the basic structure of steroids?

Answer 44

3 six- carbon rings 1 five- carbon ring

Question 45

in steroids what do different "R" groups cause?

Answer 45

different function

Question 46

what do steroids do? what do they play a role in?

Answer 46

communication and cell structure

Question 47

what are oxylipins?

Answer 47

oxygenated metabolites of fatty acids

Question 48

where do eicosanoids originate from?

Answer 48

oxylipins (eicosanoids are a subset of oxylipins)

Question 49

what are eicosanoids?

Answer 49

polyunsaturated fatty acids have 20 carbon atoms!

Question 50

where are many oxylipins derived from?

Answer 50

fatty acid arachidonic acid (type of fatty acid) other unsaturated fatty acids

Question 51

are oxylipins stored?

Answer 51

not generally, but they are synthesized as needed

Question 52

what is the main function of oxylipins?

Answer 52

communication within cells and between cells

Question 53

what type of molecules are proteins?

Answer 53

macromolecules

Question 54

what are macromolecules?

Answer 54

Macromolecules are made up of single units known as monomers that are joined by covalent bonds to form larger polymers

Question 55

what are proteins made up of?

Answer 55

linear chains of amino acids

Question 56

how many amino acids are there?

Answer 56

20

Question 57

how many amino acids are essential?

Answer 57

9

Question 58

how do we gain these essential amino acids?

Answer 58

consume them

Question 59

why are 11 amino acids not essential?

Answer 59

we can synthesize them

Question 60

are amino acids diverse? why/

Answer 60

yes, because theres a lot of them and because some are acidic, basic, polar, non-polar, bulky or small

Question 61

what is a short chain of amino acids called?

Answer 61

a peptide

Question 62

what is a long chain of amino acids called?

Answer 62

proteins

Question 63

proteins have complex structures, what are the 4 structures?

Answer 63

primary secondary tertiary quaternary

Question 64

how is the structure of the amino acid determined?

Answer 64

by the sequence of amino acids that make them up (sequence is encoded in the genome)

Question 65

what is a primary structure?

Answer 65

sequence of amino acids

Question 66

what are two forms of the secondary structure?

Answer 66

alpha helix beta pleated sheets

Question 67

proteins are the tools of cells and are very versatile, in a given mammalian cell how many different proteins might be expressed?

Answer 67

10,000 - 15,000

Question 68

what is the difference between fibrous proteins and globular proteins?

Answer 68

fibrous proteins are insoluble globular proteins are soluble

Question 69

there are 7 categories of soluble proteins, what are they?

Answer 69

enzymes membrane transporters signal molecules receptors binding proteins regulatory proteins immunoglobulins

Question 70

function of enzymes

Answer 70

help speed up metabolism, or the chemical reactions in our bodies

Question 71

function of membrane transporters

Answer 71

catalyzes the translocation of solutes

Question 72

function of signal molecules

Answer 72

transmit information between cells

Question 73

function of receptors

Answer 73

detect the signals and then send them to the brain in the form of electrical signals

Question 74

function of binding proteins

Answer 74

regulate many cellular processes

Question 75

function of regulatory proteins

Answer 75

regulates other biological processes

Question 76

function of immunoglobulins

Answer 76

protecting against bacteria, viruses, and fungi (recognize parts inside our bodies that arent supposed to be there

Question 77

in order for a protein to do something, what does it need to interact with?

Answer 77

other proteins, molecules or ions by binding or interacting

Question 78

what is a molecule that binds to a protein binding site called?

Answer 78

ligand

Question 79

what is an endogenous ligand?

Answer 79

something natural in your body, example is hormone or neurotransmitter

Question 80

what would non- endogenous be?

Answer 80

a drug or toxin

Question 81

a protein binds a ligand with affinity, what would high and weak affinity mean?

Answer 81

high: binds strongly weak: weak binding

Question 82

what would the agonist (good guy) be in light of a ligand?

Answer 82

a ligand that binds to a protein binding site and alters the state of the protein ex. hormone or drug

Question 83

what would an antagonist (bad guy) be in light of a ligand?

Answer 83

a ligand that reduces the action of an agonist also called inhibitors or blockers

Question 84

agonists and antagonists may be competitive, what does that mean?

Answer 84

acts to block the agonist (good) at its normal binding site

Question 85

agonists and antagonists may be allosteric, what does that mean?

Answer 85

acts to block a competitive agonist by binding to the protein away from the binding site and inactivate the binding site

Question 86

what 5 factors alter protein binding?

Answer 86

isoforms cofactors activation/ protein processing physical factors (pH, temperature) modulation

Question 87

what are examples of covalent modification or modulation?

Answer 87

phosphorylation and dephosphorylation addition of lipid or carbohydrate agonist/ antagonist

Question 88

what is phosphorylation?

Answer 88

enzyme transfers (adds) a phosphate onto one of the amino acid side chains of a protein

Question 89

how was glycogen metabolism regulated?

Answer 89

by the addition or removal of a phosphate

Question 90

how many proteins in a mammalian cell are covalently bound to phosphate?

Answer 90

one third

Question 91

what charge do phosphates have?

Answer 91

negative

Question 92

what do phosphates being negatively charged have to do with their addition to a protein?

Answer 92

the negative phosphate will change the characteristics of the protein (causes the protein to change how it is structured)

Question 93

how can the transfer of phosphates onto proteins be catalyzed?

Answer 93

by a variety of enzymes called protein kinases

Question 94

what enzymes are responsible for the reverse reaction in which phosphates are removed from a protein?

Answer 94

protein phosphatases

Question 95

what are the 3 advantages of phosphorylation/ dephosphorylation of a protein as a control mechanism/

Answer 95

it is rapid does not require new proteins to be made or degraded easily reversible

Question 96

what does the reception of a signal on the surface of a cell result in?

Answer 96

the activation of kinases and phosphatases

Question 97

does phosphorylation cause activation or inhibition?

Answer 97

can cause both

Question 98

who won the nobel prize for discovering phosphorylation and dephosphorylation? (2)

Answer 98

edwin krebs and edmond fisher 1992