Ch 2. Biochem Simple

Front 1

Reducing agents

Back 1

Supply hydrogen atoms, or electrons in chemical agents.

Front 2

Oxidizing agents

Back 2

Receive hydrogen atoms or electrons.

Front 3

NADH, NADPH and FADH2 are all examples of? What are their individual functions?

Back 3

"Reducing agents" with reducing power. Thus, they can hydrogen.

Biosynthesized molecules become more reduced with synthesis, so the energy supplied by NADPH generally is used for a variety of biosynthesis (rather than ATP generation).

NADH and FADH2 are involved in ATP production, as we will learn in a discussion regarding oxidative phosphorylation.

Front 4

ATP, Creatinine-phosphate, UTP, and GTP transfer what groups in the energy delivery process?

Back 4

Phosphoryl groups.

Glucose + ATP--> Glucose 6-P + ADP

Creatining Phosphate + ADP --> Creatine + ATP

Front 5

NADH, NADPH, and FADH2 transfer what groups during energy transfer?

Back 5

Electrons, and hydrogen.

Pyruvate (CH3)CO(COOH) + NADH-->NAD + Lactate (CH3)(HCOH)(COOH)

Front 6

Biotin transfers what group during the energy transfer process?

Back 6

CO2

Pyruvate (CH3)(CO)(COOH) +Biotin-CO2 --> Biotin + Oxaloacetate (COOH)(CH2)(CO)(COOH)

Front 7

Acetyl CoA or CoA-SH transfers what energy group during the energy transfer process?

Back 7

Acyl group.

Acetyl CoA+ Oxaloacetate--> CoA-SH + Citrate

Front 8

Activated Tetrahydrofolate transfers what energy group during the energy transfer process?

Back 8

Single carbons

dUMP + THF-C --> DHF + TMP

Front 9

Thiamine pyrophosphate (Thpp) transfers what group during energy transfer?

Back 9

Aldehyde group.

Xylulose 5-P(C5) + Erythrose 4-P(C4) + Thpp--> Fructose 6-P (C6) + glyceraldehyde 3-P (CD)

Front 10

S adenosylmethionine transfers what group during energy transfer?

Back 10

Methyl group.

SAM (S-Adenosylmethionine + R) --> S-Adenosylhomocysteine + R-CH3

Front 11

Uridine Diphosphate glucose (UDP-Glucose) transfers what energy group during energy transfer?

Back 11

Glucose.

Amylose (glucose-gucose) + UDP-GLucose--> UDP + extended amylose (glucose-glucose-glucose)

Front 12

Hexokinase

Back 12

Hexokinase enzyme facilitates the rx. towards G6P (Glucose-6-phosphate or D2) from glucose.

Front 13

Glucose-6-phosphatase

Back 13

Facilitates the rx. towards glucose from glucose-6-phosphatase.

Front 14

Phosphofructokinase

Back 14

Phosphorylates Fructose 6-P to make Fructose 1,6-P2

Front 15

In regards to enzymes that catalyze reactions that proceed in opposite directions, do those reactions occur in the same location/simultaneously?

Back 15

No, if they did, the reactions would compete with one another, generating a continuous cycling that only wastes energy. This would produce heat and ATP (and may be involved in malignant hyperthermia).

These reactions are placed near each other on paper, yet are separated in the body--either various organelles or in different organs. (Ex: biosynthesis/biodegradation)

Front 16

How does the body prevent enzymes that catalyze reactions that proceed in opposite directions from acting concurrently?

Back 16

Negative and Positive Feedback Systems.

Front 17

Enzymes vs. Hormones

Back 17

Enzymes- control reaction rates

Hormones- directly/indirectly affect degree of enzyme synthesis/activation

Front 18

List the biochemical reactions that occur in the mitochondria

Back 18

1. Krebs cycle
2. Fatty Acid oxidation
3. Formation of Acetyl Coa
4. Part of the Urea Cycle
5. Part of gluconeogenesis
6. Part of Heme Synthesis

Front 19

List the biochemical reactions that occur in the golgi apparatus

Back 19

Synthesis and packaging of complex molecules including
1. glycolipids
2. glycoproteins
3. lipoproteins

Front 20

List the biochemical reactions that occur in the cytosol

Back 20

1. Glycolysis
2. HMP shunt
3. Protein Synteshsis
4. Fatty Acid Synthesis
5. Part of the Urea Cycle
6. Part of gluconeogesnsis
7. Part of Heme Synthesis

Front 21

List biochemical reactions that occur in (A) lysosomes and (B) peroxisomes

Back 21

They contain (A) Hydrolytic and (B) oxidative enzymes

Front 22

List biochemical reactions that occur in the nucleus

Back 22

DNA and RNA Synthesis

Front 23

Major sites in the body where fatty acid synthesis occurs?

Back 23

Liver and Fat Cells

Front 24

Main sites in the body where gluconeogenesis occurs?

Back 24

Liver and Kidney cells

Front 25

Main sites in the body where Heme synthesis occurs?

Back 25

Bone marrow

Front 26

Main sites in the body where HMP Shunt rx. occurs?

Back 26

Liver, fat cells, adrenal cortex, mammary gland, and red blood cells

Front 27

Main sites in the body where aminoi acid synthesis and breakdown occurs?

Back 27

Liver

Front 28

Major sites in the body where Urea synthesis occurs?

Back 28

Liver

Front 29

Main sites in the body where cholesterol and bile acid synthesis occurs?

Back 29

Liver

Front 30

Main sites in the body where steroid hormone synthesis occurs?

Back 30

Adrenal cortex and Gonads

Front 31

In the Krebs cycle, intramitochondrial NADH and FADH2 yields how many ATPs?

Back 31

3 ATPs for NADH

2 ATPs for FADh2

Front 32

In the Krebs cycle, Extramitochondrial NADH (generated in the cytosol "main hallway") yields how many ATPs?

Back 32

2 ATPs (this is because NADH cannot pass through mitochondrial membrane--it requires Glycerol-3-P (Glycerol Phosphate Shuttle)

Front 33

In the Kreb's cycle, one GTP produces:

Back 33

1 ATP

Front 34

Cytochromes

Back 34

Heme-containing proteins that participate in electron transport through valence changes in heme iron.

Front 35

In what chemical form do carbons enter the krebs cycle? What are the carbon end protects of krebs cycle?

Back 35

For every 2 carbons that get on the krebs cycle as acetyl CoA, two carbons get off as CO2 (of course they aren't the exact same 2 carbons, but that's another matter and is beside the point).

Degredation of two carbons to form CO2 releases energy that is captured to form ATP.

Front 36

Acetyl CoA that enters the krebs cycle can be replinished via what mechanisms?

Back 36

1. glucose breakdown
2. fatty acid degradation (fatty acid ox)
3. amino acid transformation

Front 37

The molecules of the actual krebs cycle are replinished how?

Back 37

Certain amino acids that can convert into Krebs cycle intermediates.

Front 38

Pyruvate from glycolysis can enter DIRECTLY into the krebs cycle how?

Back 38

Biotin catalyzes a reaction in which pyruvate (C3) becomes oxaloacetate, and direct entry into the Krebs cycle can occur.

Front 39

What other 6-carbon sugar can be split and used as fuel for glyolysis?

Back 39

Fructose

Front 40

What substrate is required for the Krebs cycle to opreate?

Back 40

Oxygen. Most ATP is produced during Krebs cycle rx. (especially during ox. phos)

Front 41

Describe energy production in the absence of oxygen?

Back 41

Anaerobic glycolysis can occur (in the main hallway) with SOME ATP production.

Normally, G3P makes it all the way to the pyruvate via several reactions that cause loss of NAD+. In the presence of oxygen, more NAD+ is lost to produce Acetyl-CoA.

In the absence of molecular oxygen (ie. during vigorous exercise) pyruvate actually restores NAD+ consumed by using NADH formed in previous reactions to form Lactate and NAD+ from pyruvate.

Front 42

NADH, FADH2, and GTP which are produced during the Krebs cycle supply electrons that are passed along a brigade of molecules that ends w/ O2 and the release of energy that changes ADP-->ADP

Back 42

Oxidative phosphorylation

Front 43

Oxidative Phosphorylation

Back 43

Oxidation by a series of reactions necessitating O2 in the final step, phosphorylation of ADP to ATP in the same chain.

Oxidation and phosphorylation are coupled (oxidative processes occur concurrently with ATP production)

Front 44

What molecule, when present, stimulates oxidation (and slows oxidation when absent)?

Back 44

ADP.

1. When ADP is high (and ATP low) ox. phos is stimulated.

When ADP is low and ATP high (ox phos is slowed)

This is a control mechanism.

Front 45

How can lipids contribute to glycolysis?

Back 45

After a short period of fasting, triglycerides (in storage) provide glycerol to the glycolysis pathway.

Front 46

How can carbohydrate storage contribute to glycolysis?

Back 46

Carbohydrate storage (glycogen which breaks down to glucose) only has enough stores to last about a day.

Front 47

How do amino acids contribute to glycolysis?

Back 47

During periods of starvation, amino acids can be converted to glycolysis pathway molecules (but it really doesn't like to do this, since it doesn't really have a nice convenient storage room, and we don't want to break down important proteins to get them. Why waste resources?)

Front 48

Functions of the "main powerhouse" or gluconeogenesis and glycolysis reactions?

Back 48

Important not only for ATP generatoin (carbohydrates, fatty acids and amino acids as fuel), but also is a source for molecules that generate:

1. carbohydrates (gluconeogenesis)
2. Lipids (lipogenesis)
3. Amino acids

Front 49

Succinyl CoA (used for the Krebs cycle) is also an important entry point into what other important synthetic pathway?

Back 49

Glycine is added to Succinyl CoA to form 2-amino-3-ketoadipate (C6) which is important for entry into the porphyrin synthetic pathway that makes Heme, cytochromes, peroxidases, catalases, bilirubin, etc.

Front 50

During anaerobic glycolysis, pyruvate transformation to lactate replinishes what?

Back 50

NAD+.

Front 51

If we ingest ethanol, we can handle it by transforming it to what compound?

Back 51

acetyl CoA (thus alcohol can be used as fuel). Thus alcohol ingestion can lead to weight gain, as acetyl CoA connects directly with lipid synthesis (the roller coaster of lipid land).

Front 52

How many ATPs result from the splitting of one glucose molecule?

Back 52

36. This is the net ATPs produced by glycolysis (cytosol), the krebs cycle/ox. phos (mitochondria) and G3P shuttle (Mitochondria)

2 from glycolysis, 30 from the Krebs Cycle, and 4 from the G3P shuttle = 36

Front 53

Gluconeognesis

Back 53

While glycolysis occurs almost universally in the body, gluconeognesis occurs predominantly in the liver and only slightly in the kidney.

Ex: Lactate formed from pyruvate during exercise must leave the muscle, travel to bloodstream where it can enter the liver (site of gluconeogenesis).

Once in the liver, the following enzymes begin acting on the lactate to convert it back into glucose:

1. Pyruvate carboxylase (Pyruvate-->Oxaloacetate).
Then oxaloacetate converts to PEP via phosphoenolpyruvate carboxykinase (PEP-CK).

2. Fructose bisphosphatase changes fructose 1,6-P2 to fructose 6-P.

3. Glucose 6-phosphatase is absent in muscle, but is present in liver. It catalyzes glucose-6-P to glucose!

Front 54

Pyruvate Carboxylase enables

Back 54

Pyruvate to become Oxaloacetate

Front 55

PEP-Carboxykinase converts:

Back 55

Oxaloacetate to PEP

Front 56

Fructose bisphosphatase

Back 56

fructose 1,6-P2 --> Fructose 6-P

Front 57

Glucose 6-phosphatase

Back 57

Absent in muscle. Converts Glucose 6-P to Glucose.

Front 58

Glycolysis may provide lipid land with what to aid in the formation of lipids?

Back 58

Acetyl CoA and Glycerol.

Front 59

Lipids provide what molecules to the main powerhouse (glycolysis) which converts it into other types of molecules or uses it as fuel?

Back 59

Acetyl CoA and Glycerol.

Front 60

Non-essential amino acids can be formed directly by what mechanism?

Back 60

Directly or indirectly, these amino acids can be formed from glycolysis pathway molecules.

Front 61

In starvation periods, what molecules can be shuttled into gluconeogenic pathways?

Back 61

Amino acids

Front 62

Succinyl CoA formed from the Krebs cycle is a precursor of:

Back 62

porphyrins and their derivates such as Heme

Front 63

Nucleic acids can be broken down and contribute to:

Back 63

molecules that indirectly transform into glycolysis/gluconeogenic pathway molecules.