Micro Chapter 12

Front 1

What is anabolism?

Back 1

The construction of molecules from carbon and inorganic sources.

Front 2

What is the relation between antibiotics and anabolism?

Back 2

Antibiotics block anabolic pathways.

Front 3

What is the pyramid for construction of cells?

Back 3

Carbon + inorganic --> precursors --> monomers--> macromolecules --> supramolecular systems --> organelles --> cells

Front 4

How is metabolism regulated?

Back 4

The rate of turnover is balanced with the rate of synthesis.

Front 5

What are the 6 principles of biosynthetic paths?

Back 5

1) macromolecules made from monomers 2) many enzymes do double function 3) anabolic paths function irreversibly in direction of biosynthesis (done by coupling breakdown of ATP to other reactions) 4) anabolic and catabolic paths are physically separated 5) anabolism takes a great deal of energy 6) anabolic and catabolic paths use different cofactors (catabolism makes NADH as electron carrier while anabolic uses NADPH)

Front 6

What are the 3 benefits of synthesizing macromolecules from monomers?

Back 6

1) saves energy 2) saves genetic storage capacity 3) saves biosynthetic raw material

Front 7

What are the 2 benefits of double duty enzymes?

Back 7

1) saves material and 2) energy

Front 8

What are used as starting substrates for the synthesis of monomers (precursor metabolites)? How many are precursor metabolites are there?

Back 8

Carbon skeletons. There are 12 precursor metabolites. Most of them make amino acids.

Front 9

How do chemoorganoheterotrophs get carbon for anabolism?

Back 9

They derive carbon from intermediates of the central metabolic pathways (versus fixing CO2).

Front 10

How do autotrophs get carbon for anabolism?

Back 10

They fixate CO2 using the Calvin Cycle, or 5 other pathways.

Front 11

Where does the calvin cycle occur in eukaryotes?

Back 11

In the stroma of chloroplasts.

Front 12

Where does the calvin cycle occur in cyanobacteria or other bacteria that can fix CO2?

Back 12

In carboxysomes.

Front 13

What must first be done to CO2 to use as carbon source?

Back 13

Must be converted to organic carbon.

Front 14

What are the 3 phases of the calvin cycle?

Back 14

1) carboxylation 2) reduction 3) regeneration

Front 15

Describe what happens during carboxylation.

Back 15

The rubisco enzyme adds CO2 to ribulose 1,5'-diphosphate. Then 2 molecules of 3-phosphoglycerate are made.

Front 16

Describe what happens during reduction phase.

Back 16

The 2 3-phosphoglycerate are reduced to glyceraldehyde 3-phosphate.

Front 17

Describe what happens during regeneration phase.

Back 17

Rubisco is reformed and the cycle repeats.

Front 18

How much ATP and NADPH is used in the incorporation of 1 CO2?

Back 18

3 ATP's and 2 NADPH's (for every 6 CO2, 18 ATP is used and 12 NADPH is used)

Front 19

What is gluconeogenesis?

Back 19

The synthesis of glucose and related sugars (fructose 6 phosphate and glucose 6 phosphate) from nonsugar molecules. The reverse of glycolysis.

Front 20

How does gluconeogenesis differ from glycolysis?

Back 20

They share 7 enzymes (7 steps in the Embden-Meyerhof path) but 4 are unique to gluconeogensis.

Front 21

What are monosaccharides? How are they synthesized?

Back 21

One sugar unit that is synthesized while attached to a nucleoside diphosphate.

Front 22

How are polysaccharides synthesized?

Back 22

From the activated forms of their monomers, often including nucleoside diphosphate.

Front 23

What is the sequence of steps for peptidoglycan synthesis?

Back 23

1) UDP derivatives of NAG and NAM are made (UDP NAG and UDP NAM) 2) Amino acids are added to UDP NAM to form NAM-pentapeptide 3) NAM-pentapeptide is transferred to bactoprenol phosphate 4) UDP transfers NAG to bactoprenol NAM-pentapeptide 5) NAG-NAM pentapeptide goes across membrane carried by bactoprenol 6) the NAG-NAM thing is added to growing chain of peptidoglycan 7) bactoprenol goes back across membrane, loses phosphate group, and can start cycle over again 8) Peptide cross links are formed by transpeptidation

Front 24

What is autolysis?

Back 24

The digestion of peptidoglycan so new can be formed-allows new material as well as cell division.

Front 25

What are 4 steps/methods part of amino acid synthesis?

Back 25

1) nitrogen assimilation 2) sulfur assimilation 3) AA synthetic paths 4) anaplerotic reactions and AA synthesis

Front 26

What are amino acids made of?

Back 26

carboxyl, amine, r group

Front 27

Where are most carbon skeletons needed for amino acids derived from?

Back 27

TCA or glycolysis

Front 28

What are the 3 potential sources of nitrogen (in order to make AA's)?

Back 28

ammonia, nitrate, nitrogen gas

Front 29

Why is ammonia the best source of nitrogen?

Back 29

It is more reduced than other inorganic forms of nitrogen

Front 30

What are the 3 enzymes that can directly incorporate nitrogen from ammonia?

Back 30

1) transaminase 2) glutamate hydrogenase 3) glutamine synthetase-glutamate synthase

Front 31

Which enzymes can transfer incorporated nitrogen to other skeletons?

Back 31

Transaminase

Front 32

What is assimilatory nitrate reduction? Who does it?

Back 32

Bacteria does it. It is reduction of nitrate to nitrite to ammonia. The opposite of dissimilatory nitrate reduction.

Front 33

Which enzyme turns nitrate into nitrite? Nitrite into ammonia?

Back 33

Nitrate reductase and nitrite reductase

Front 34

Why is nitrate converted to ammonia?

Back 34

Because ammonia is more reduced than nitrate and that makes it easier to convert to organic form

Front 35

What is nitrogen fixation? Who does it?

Back 35

fixing N2 gas to ammonia: only done by bacteria and archaea. It makes 2 NH3 for every N2.

Front 36

What enzymes performs nitrogen fixation?

Back 36

Nitrogenase. It is very sensitive to oxygen so bacteria use leghemoglobin to protect it.

Front 37

What is assimilatory sulfate reduction?

Back 37

When sulfate is reduced to H2S. This H2S makes cysteine (an amino acid). Then cysteine makes sulfur containing compounds.

Front 38

What are the most common sources of phosphate?

Back 38

inorganic phosphate and organic phosphate esters

Front 39

Which enzymes hydrolyzes organic phosphates to make inorganic phosphates?

Back 39

Phosphatase

Front 40

How is inorganic phosphate incorporated?

Back 40

Through the formation of ATP (oxidative phosphorylation, photophosphorylation, SLP)

Front 41

How is organic phosphate incorporated?

Back 41

1) environment 2) hydrolyzed by phosphatase

Front 42

What are the initial products in the synthesis of purines and pyrimidines?

Back 42

Ribonucleotides

Front 43

What is the structure of a purine? Pyrimidine? Nucleoside? Nucleotide?

Back 43

Purine (adenine or guanine) is 2 joined rings that form cyclic nitrogen bases. Pyrimidine is one ring that forms a cyclic nitrogenous base. Nucleoside is just a pentose sugar and a nitrogen base. Nucleotide is pentose sugar, n base, and a phosphate.

Front 44

What kind of lipids do fatty acids form?

Back 44

Phospholipids, triacylglycerols

Front 45

What are fatty acids synthesized from?

Back 45

acetyl cOa, malonyl co A, NADPH by FA synthase system

Front 46

What is self assembly?

Back 46

Construction of organized systems without outside help i.e. ribosomes

Front 47

What is one other pathway that fixes CO2?

Back 47

1) reductive TCA cycle...

Front 48

What 2 enzymes are specific to calvin cycle?

Back 48

rubisco and glyceraldehyde 3 phosphate

Front 49

What are nucleoside diphosphate sugars?

Back 49

activated forms of monosaccharides