Molecules to Metabolism

Question 1

what is molecular biology

Answer 1

chemistry of living organisms

Question 2

what is metabolism

Answer 2

web of all enzyme-catalysed reactions in a cell or organism

Question 3

what are the three factors that determine whether a collision leads to a chemical reaction

Answer 3

identity of colliding molecules
orientation of colliding molecules
speed of molecules upon collision

Question 4

what are enzymes

Answer 4

protein molecules that have a specific shape in which a reactant can fit

Question 5

list five examples of metabolism

Answer 5

replication of dna for cell division
synthesis of rna for chemical communication between nucleus and cytoplasm
synthesis of protein (bonding of one amino acid to another)
cell respiration (nutrients -> atp)
photosynthesis (light -> carbohydrates)

Question 6

what is metabolism made up of

Answer 6

metabolism = catabolism + anabolism

Question 7

what is catabolism

Answer 7

break down of complex molecules into simpler molecules

• releases water when bonds are broken (exergonic)
• uses water
• typically involves oxidation
• hydrolysis of macromolecules into monomers
• > lactose + water –> glucose + galactose
• > starch + (many) water –> (many) glucose
• > protein + (many) water –> (many) amino acids
• > triglyceride + 3 water –> glycerol + 3 fatty acids

Question 8

what is anabolism

Answer 8

synthesis of complex molecules from simpler molecules

• uses energy to construct new bonds (endergonic)
• typically involves reduction
• condensation of monomers into macromolecules (opposite of hydrolysis)
• > amino acids –> protein + (many water)
• > water molecules are products rather than reactants

Question 9

what is a condensation reaction

Answer 9

creates water when bonds joining molecules are formed

Question 10

what is a hydrolysis reaction

Answer 10

requires water to break the bonds between molecules

Question 11

list the four common carbon compounds

Answer 11

carbohydrates (monosaccharide)
- source of energy/short term storage/structural component (dna/rna)
lipids (fatty acids)
- cell membranes/long term energy storage
proteins (amino acids)
- regulatory molecules involved in catalysis/structural molecules
nucleic acids (nucleotides)
- dna (code for protein assembly)/rna (code for protein synthesis)

Question 12

how many covalent bonds does carbon form

Answer 12

4

Question 13

list 4 monosaccharides

Answer 13

glucose
galactose
fructose
ribose

Question 14

list 3 disaccharides

Answer 14

maltose
lactose
sucrose

Question 15

list 3 polysaccharides

Answer 15

starch
glycogen
cellulose

Question 16

list 2 polypeptides (proteins)

Answer 16

enzymes

antibodies

Question 17

what are some characteristics of lipids

Answer 17

insoluble in water
contains:
triglycerides
phospholipids
steroids
fatty acids
waxes

Question 18

what are nucleic acids

Answer 18

chains of nucleotides
contains:
dna
rna
atp

Question 19

what is vitalism

Answer 19

belief that living organisms and inanimate things differed fundamentally because living organisms contained a non-physical or vitalistic element and were subject to different principles of nature
- organic molecules (urea) of living organisms can only be synthesised by living organisms

Question 20

what does vitalism state about urea

Answer 20

urea cannot be produced outside of the body

Question 21

how was vitalism disproved

Answer 21

friedrich wohler mixed cyanic acid and ammonium to create urea crystals in 1828
- urea is produced in the body as a waste product of nitrogen metabolism and is eliminated by the kidneys in mammals

Question 22

what are some common biochemical substances

Answer 22

beta-d-glucose
alpha-d-glucose
generalised fatty acid
generalised amino acid
saturated fatty acids
- monounsaturated
- polyunsaturated

Question 23

how to distinguish between carbs/proteins/lipids

Answer 23

proteins contain CHON sometimes S (carbon hydrogen oxygen nitrogen) (sometimes sulfur)
carbs and lipids never contain N or S
carbons H:O is close to 2:1
lipids contain a lot less O