Unit1:Biomolecules Flashcards

Question

What two monosaccharides form sucrose (table sugar)?

Answer 1

fructose and glc

Answer 2

i. Energy for cells Ø Glucose metabolism forms ATP (adenosinetriphosphate) ii. Structural component of other biomolecules (DNA & RNA) Ø E.g.1: DNA contains deoxyribose Ø E.g.2: RNA contains ribose iii. Structural component of cells – e.g. can be bound to lipids and proteins to form glycolipids and glycoproteins which have important roles in the structure and function of cell membranes.

Answer 3

Consist of C, H, and O, but in a different ratio than carbohydrates (less oxygen); some have N and P

Answer 4

Hydrophobic (insoluble in water)

Answer 5

- FA - glycerides - phospholipids -sphingolipids - steroids - eicosanoids

Answer 6

Ø Long hydrocarbon chains with 8-28.carbon Ø Has a carboxyl (-COOH) functional group (= acidic) - can be saturated or unsaturated

Answer 7

no double bonds between carbon atoms so forms a straight chain Solid at room temperature. E.g. palmitic acid (palm oil, butter, animal fats); stearic acid (butter, chocolate, lard); lauric acid (coconut oil).

Answer 8

has double bonds between carbon atoms

Answer 9

One double bond e.g. oleic acid (most common in nature, part of triglycerides and phospholipids that make cell membranes; olive oil).

Answer 10

Two or more double bonds e.g. linoleic acid (found in canola oil, sunflower oil, nuts, seeds); arachidonic acid The more double bonds, the less likely the fat is to be soluble at room temp

Answer 11

Formed from fatty acids and glycerol via dehydration synthesis (glycerol gives up the hydrogen atoms from its hydroxyl group, which combine with the -OH of the fatty acid carboxyl group to form water)

Answer 12

Ø Glycerol + 1 fatty acid

Answer 13

Glycerol + 2 fatty acids

Answer 14

Glycerol + 3 fatty acids are an important form of stored energy in the body (adipose/fat tissue).

Answer 15

Ø Derived from glycerides. Essentially a diglyceride to which a phosphate group (PO 4) and a variable R group have been added. Ø Glycerol + 2 fatty acids + PO 4 + variable R group Ø R group – Allows the formation of of different types of phospholipids. e.g -group = serine, forms phosphatidylserine, if R -group = choline, forms phosphatidylcholine.

Answer 16

Are amphipathic molecules – have both hydrophilic and hydrophobic regions. Polar heads (phosphate + R-group) are hydrophilic, and non- polar fatty acid tails are hydrophobic. Ø Phospholipids can arrange themselves into bilayers, micelles and liposomes. Polar heads face the ECF or ICF, non-polar tails towards each other

Answer 17

Ø Modified phospholipids. Ø Sphingolipids incorporate a sphingosine molecule instead of glycerol and have only 1 fatty acid. Ø form lipid rafts on cell membranes that may help to protect the cell surface.

Answer 18

a phospholipid with a carbohydrate group attached (usually a polysaccharide)

Answer 19

a sphingolipid with a carbohydrate group attached

Answer 20

Basic structure consists of three 6-carbon rings plus one 5 carbon ring (17 carbons total). Ø Many derived from cholesterol. Ø Different functional groups (R-groups) give steroids their different functions. Ø Play roles in communication (hormones) and cell structure Ø E.g.1: Cholesterol (stabilizes cell membranes) Ø E.g.2: Cortisol (stress hormone) Ø E.g.3: Testosterone & Estrogen (reproductive hormones)

Answer 21

Ø Polyunsaturated fatty acids with a length of 20 carbons (“eicos-” = Greek for 20) attached to a complete or partial carbon ring. Contains oxygen atoms. Ø Many derived from arachidonic acid or other unsaturated fatty acids. Ø Synthesized as needed (not stored) Ø Unlike most lipids, Eicosanoids are often able to cross cell membranes. Ø They Function in communication within and between cells. Ø E.g.1: Prostaglandins (help mediate inflammation and pain response during injury/infection among other roles) Ø E.g.2: thromboxane (important for blood clotting – specifically platelet aggregation

Answer 22

i. Cell structure – important components of cell membranes and organelles. ii. Energy source – e.g. triglycerides in adipose tissue of the human body is a large store of energy. iii. Communication (within and between cells

Answer 23

i. a 5-carbon sugar (ribose, deoxyribose) ii. a phosphate (PO4) group iii. A nitrogenous base (carbon-nitrogen ring structure) Ø Nitrogenous bases are either purines (2 rings) or pyrimidines (single ring). Ø Purines = adenine + guanine Ø Pyrimidines = Cytosine, Thymine, Uraci

Answer 24

re nucleotides minus the phosphate group.

Answer 25

Macromolecules that consist of C, H, O, N (and sometimes S (polymers of aa's )

Answer 26

monomers basic units of protein structure

Answer 27

central carbon atom to which is attached: Ø Carboxyl group (-COOH) Ø Amino group (-NH2) Ø R-group (functional group – determines the structure of the amino acid

Answer 28

Ø 9 are essential and we need to consume them in the foods we eat (e.g. leucine, tryptophan, valine, etc.) Ø 11 are non-essential, the body synthesizes them (e.g. tyrosine, glycine, etc.

Answer 29

joins aa's together thru a dehydration reaction

Answer 30

short chains of amino acids (oligopeptides = 2-9 amino acids; polypeptides = 10-100 amino acids)

Answer 31

long chains of amino acids (>100 aa

Answer 32

the sequence of amino acids in the chain

Answer 33

hydrogen bonds between adjacent amino acid chains or loops within the same chain create b-sheets and a-helices (helix = singular) respectively

Answer 34

a-helices and b-sheets combine to form globular or fibrous proteins. Globular proteins are usually soluble, while fibrous proteins are not.

Answer 35

multiple tertiary structures combine to form the finished protein (e.g. hemoglobin has 4 globular protein subunits)

Answer 36

n order for a protein to do something, it must interact with or bind to other proteins, molecules or ions

Answer 37

where the ligand binds

Answer 38

also known as substrate - Molecules that bind to protein binding sites.

Answer 39

ligands naturally present in body (e.g. hormones and neurotransmitters)

Answer 40

enter the body from the external environment and include drugs/toxins

Answer 41

a ligand that binds to a protein binding site and alters the state of the protein resulting in a biological response. E.g. a hormone, neurotransmitter, or drug

Answer 42

a ligand that reduces the action of an agonist (i.e. binds to the protein but causes no biological responses) Also called inhibitors, blockers

Answer 43

Ø Antagonists may be competitive: bind to the same binding site as the agonist. Ø Antagonists may be allosteric: bind to to a different site than the agonist, but this interaction inactivates the binding site.

Answer 44

– refers to strength of the binding between the protein and the ligand. Ø High affinity = protein binds the ligand strongly Ø Low affinity = protein binds the ligand weakly

Answer 45

isoforms – proteins whose structure and functions are similar, but that have different affinities for the same ligand. E.g. fetal hemoglobin has a higher affinity for oxygen than adult hemoglobin Activation/protein processing protein must be converted into its active form before any binding/activity can take place. Proteolytic activation Ø E.g. Pepsinogen in the stomach undergoes proteolytic activation by HCl, which converts it into its active form pepsin (pepsin is an enzyme involved in protein digestion) Cofactors ions (e.g. Ca++) or molecules that must attach to the protein in order for the binding site to become active. If no cofactor is present, binding/activity stops. Modulation Changes ability of protein to bind to the ligand or changes the response of the protein to the binding of the ligand Physical factors, like pH and temperature

Answer 46

antagonist binds to binding site and cannot be removed (even if the concentration of agonist increases)

Answer 47

antagonist binds reversibly to binding site. Level of activity/binding of agonist depends on relative concentrations of agonist and antagonist. More antagonist = more inhibition, less activity. More agonist = less inhibition, more activit

Answer 48

modulator binds to site other than agonist binding site. May cause inhibition or activation of agonist binding site.

Answer 49

atoms or functional groups (like phosphates) bond covalently to the protein altering its structure and changing its activity (increase or decrease) a) Phosphorylation and Dephosphorylation – addition or removal of a phosphate group changes the protein’s activity. Common action of protein kinases. b) Addition of a lipid or carbohydrate

Answer 50

Protein/enzyme activity depends on the amount of ligand present and the amount of protein present. Ø When concentration of ligand is higher than available protein binding sites can handle, binding sites are completely filled and saturation is reached. Ø Enzymes, membrane transporters, receptors, binding proteins, etc can all reach a saturation point (the point where addition of more ligand will not make any difference in activity because all binding sites on the proteins involved in the process are occupied). Figure 2.13

Answer 51

any substance dissolved in solvent

Answer 52

liquid into which solute dissolves

Answer 53

Ability of a solute to dissolve a solve

Answer 54

Ø dissociate in water releasing H+ ØHigher [H+] = lower pH ØE.g. hydrochloric acid (as produced by the stomach) has a pH of 2

Answer 55

Ø substances that bind free H+ ions in solution and so decrese [H+] in solution.. Ø Lower [H+] = higher pH

Answer 56

measure of the free H+ ion concentration in a solution. Ø pH = -log [H+] or pH = log (1/[H+]) ØpH >7 = alkaline (basic); pH < 7 = acidic Ø Log scale, so every time the pH sacel goes up or down by 1, this represents a 10X increase or decrease in the [H+].

Unit1:Biomolecules Flashcards

(80 cards)