study guide

What is the key building block of cholesterol biosynthesis

isopentyl pyrophosphate

What is a typical cofactor for biosynthesis reactions

NADPH

What is the rate limiting enzyme of palmitate biosynthesis

Acetyl CoA Carboxylase

What is the rate limiting step of cholesterol biosynthesis

HMG CoA reductase

What is the correct order of the intermediates as they appear in the B-oxidation pathway

1. Acyl Coa

2. trans-enoyl coa

3. L-3-Hydroxyacyl Coa

4. 3-ketoacyl CoA

5. Acyl CoA + Acetyl CoA

Correct order of the enzymes at they appear in B-oxidation pathway

1. Acyl Coa dehydrogenase

2. Enoyl CoA Hydratase

3. Hydroxyacyl CoA dehydrogenase

4.8-ketothiolase

Which molecule in the above list is made from a reaction that requires the oxidant Flavin Adenine Dinucleotide?

trans -enoyl Coa

what structures is this ?

acyl coa

What is the underlying cause of Respiratory Distress Syndrome

• Starts b/c of insufficient generation of the surfactant dipalmitoyllecithin by type 2 cells in lung

• in premature infants: lack of type 2 maturation

• in adults : caused by chemotherapeutics that harm/kill type 2 cellls

What is the use of surfactant

• needed to prevent atelectasis

• Providing surfactant to the lung and in premature babies resolves over time as type 2 cells mature

what is atelectasis

Collapse of the alveolus in the lung due to water self-adhesion when the alveolus deflates during exhalation

What is the product of the non-enzymatically driven light-reaction that is one way on which humans photosynthesize

Previtamin D3

What enzymes consumes FAD during Beta-Oxidation

Acyl CoA dehydrogenase

Which enzyme consumes NAD+ in B-oxidation

L-3-hydroxyacyl CoA dehydrogenase

which enzyme consumes H2O IN B oxidation

enoyl coa hydratase

which enzyme consumes HS-CoA in b-oxidation

b-ketothiolase

What role does malate play in palmitate biosynthesis

• Is converted to pyruvate by malic enzyme

• produce NADPH

• CO2

What is the key building block of palmitate

Malonyl CoA

Which of the following molecule is immediate result of enzymatic oxidation -reduction

• acetyl coa

• hydroxyacyl coa

beta -oxidation occurs in what sub cellular compartment

matrix of the mitochondria

glycolysis occurs in what sub cellular compartment

cytoplasm of the cell

In palmitate biosynthesis what is the purpose of citrate

Transports acetyl CoA out of the matrix of the mitochondria into the cytosol

From the statement below, select if (1) or (2) or both or neither are false. ( A) Malonyl has 3 carbons , (B) therefore when malonyl (ACP) combines with acetyl (APC) in palmitate biosynthesis a four carbon chain is generated

true to both statements

When a triacylglyceride is broken down to glycerol, what happens to the glycerol

Glycerol is transported to the liver and becomes pyruvate via glycolysis or glucose gluconeogenesis

The enzyme acyl-CoA synthetase possesses an equilibrium constant of 1. What prevents the backwards reaction from ocurring

• Pyrophosphatase cuts PPi to prevent backflow

• Second enzyme removes key reactant

True or False; In both B-oxidation and Palmitate biosynthesis, the final enzymes use the energy of a thiol bond to release the product

True

what is the name of this intermediate

trans - enoyl CoA

what is the name of the intermediate

L-3-Hydroxyacyl CoA

What is this intermediate

3- ketoacyl Coa

What is this intermediate

acyl CoA (shortened by 2 carbons)

what is the intermediate

acetyl coa

Which primary building block is this

Malonyl CoA- palmitate

Which primary building block is this

isopentyl pyrophosphate - cholesterol biosynthesis

Assuming you have 3-isopentenyl-pyrophosphate, how many of the basic building block are needed to create cholesterol?

What are roles for cholesterol

• cell membranes, bile salts to dissolve fats (cell membrane), steroid hormones

• bile salts solubilize cholesterol

• protects gall bladder from bile salts

• disturbance in phospholipid metabolism results in gall stones

• immediate precursor to bile acids to absorb diet triacylglycerols and fat soluble vitamins

• precursor ro steroid hormones

• abundant in myelinated structures

List a combination that could result in squalene

• farnesyl pyrophosphate + farensyl pyrophosphate

Consider the iterative synthetic process for cholesterol.What is the primary energy source

Phosphoryl transfer/release

what role does malate play in gluconeogenesis

Carries OOA out of mitochondria, contributes to glucose-6-phosphate production