Pre –Exam Test (223, 224 PHL)
Question I: Choose ONE correct answer:
1- In starvation, which of the following is (are) false:
a) stored fat will be a major source of energy
b) anti-insulin hormones are released
c)
acetyl CoA carboxylase is inhibited
d) HSL is dephosphorylated
e) β-oxidation is inhibited
2- Which of the following concerning long chain fatty acids is True?
a) They are fatty acids that contain 10 carbon atoms or more
b) After their absorption into intestinal mucosa, they directly enter blood
c) Palmitic and stearic acids are examples of healthy unsaturated long chain fatty
acids
d) As all free fatty acids, they are transported in blood by albumin
e) They are activated and oxidized in mitochondrial matrix of liver, muscles and
adipose tissues
3- In carnitine shuttle, the transfer of acyl group from acyl carnitine to CoA is catalyzed by:
a) CAT-1 in cytoplasm
b) CAT-2 in cytoplasm
c) CAT-2 in mitochondria
d) Carnitine acylcarnitine translocase
4- The four carbon atoms produced in the first cycle of fatty acid synthesis are derived from:
a) Acetyl CoA
b) Acetyl CoA and malonyl CoA
c) Malonyl CoA
d) Malonyl CoA and CO2
5- One of the following fatty acid can’t be synthesized by elongation or desaturation of
palmitic acid in the mitochondria? Why?
a)
b)
c)
d)
Stearic acid
Oleic acid
Linolenic acid
Palmitoleic
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Question II: Give the name and Draw the structure of:
1- Active form of C16:0 fatty acid
2- Phospholipid that act as lung surfactant
Question III: explain why:
1-Weight loss in case of uncontrolled diabetes.
a-…………………………………
b-…………………………………
2- Heavy meal (high CHO and protein) leads to lipogenesis, while β-oxidation is inhibited
3- Glucagon, but not insulin, is important for HSL activation.
4- Malonyl CoA is essential in fatty acid synthesis. two reasons???
a…………………………………………………………………….
b-…………………………………………………………………….
5- citrate is also important in fatty acid synthesis. two reasons????
a)………………………………………………………………….
b)…………………………………………………………………..
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Question IV: Complete the following statements
1-
………………………………….is the precursor of fatty acid synthesis and is
derived from………………………………………………………………………..
2-
Pamitoyl
CoA, the end product
of fatty acid synthesis, is
formed
in……………….of the ………………. ……(name the organs). The pathway will
be then stopped because…………………………………………………………..
3-
The two sources of depot fat are…………………….and…………………………
4-
Chylomicron is a lipoprotein synthesized in……………………………….to carry
………………………………….from………………….to………………………
5-
In carnitin shuttle, the enzyme that present in both cytoplasm and mitochondrial
matrix is………………………………………………the functions of this enzyme
are…………………………………………………………………………………
…. …………….. …………………………………………………………………..
Question V:
Calculate the net energy (ATP) produced from oxidation of one molecule of lignoceric acid
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