Bioch 11,12,13,14,15...Q - maryam2009

[ArchivalUser]

11. In a sedentary fasting state, skeletal muscle spares blood glucose. All of the following are important in this process EXCEPT
a. By using mostly fatty acid, muscle needs less glucose for energy production
b. At low insulin levels, fatty acid mobilization is increased
c. At low insulin levels, acetyl CoA carboxylase is activated
d. The more energy produced from fatty acids, the less glucose needs to be oxidized
e. in a sedentary fasting state, most of the glut4 transporter have been removed from the muscle cell membrane

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12. 1. Which of the following is False?
a. Glycerol released into the blood can be converted into PGAL and go onto glycolytic and gluconeogenic pathways
b. Monoacylglycerol lipase cleaves fatty acid off carbon 2 in the adipose tissue
c. Hormonal sensitive lipase is active when phosphorylated
d. Hormonal Sensitive lipase cleaves fatty acid off carbon 1 in the blood
e. Monoacylglycerol and hormonal sensitive lipase are enzymes that cleave ester linkages off the glycerol backbone

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13. The blood of a person who consumes large amounts of animal fat would most likely contain
a. increased levels of chylomicrons
b. increased levels of VLDL
c. increased levels of HDL
d. increased levels of LDL
e. decreased levels of cholesterol

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14. . All of the following statements about the regulation of fatty acid mobilization (release from adipose) are true EXCEPT
a. The control enzyme is called hormone sensitive lipase
b. Insulin activates a protein phosphatase that removes a phosphate from hormone sensitive lipase
c. Cortisol inhibits hormone sensitive lipase using the cAMP cascade
d. Epinephrine activates hormone sensitive lipase using the cAMP cascade
e. Glucagon activates hormone sensitive lipase using the cAMP cascade

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15. where is cholesterol synthesis pathway
a. cytosol
b. mitochondria
c. endoplasmic reticulum
d. nucleus
e. both mitochondria and cytosol

[ArchivalUser]

11. C
12. C
13. B
14. C
15. A

[ArchivalUser]

11-d
12-a
13-a
14-c
15-b
???

thanks

[ArchivalUser]

11.C
12.D
13.A
14.C
15.A


I know some of those Qs wrer not easy,and I think a small amount of exposure to them is beneficial.

Good job.
Thank you

Hormonal Sensitive lipase :
HSL functions to hydrolyze the first fatty acid from a triacylglycerol molecule, freeing a fatty acid and diglyceride. It is also known as triglyceride lipase, while the enzyme that cleaves the second fatty acid in the triglyceride is known as diglyceride lipase, and the third enzyme that cleaves the final fatty acid is called monoglyceride lipase. Only the initial enzyme is affected by hormones, hence its hormone-sensitive lipase name. The diglyceride and monoglyceride enzymes are tens to hundreds of times faster, hence HSL is the rate-limiting step in cleaving fatty acids from the triglyceride molecule

HSL is activated when the body needs to mobilize energy stores, and so responds positively to catecholamines, ACTH, and negatively to insulin. Previously, glucagon was thought to activate HSL, however the removal of insulin's inhibitory effects ("cutting the brakes") is the source of activation. The lipolytic effect of glucagon in adipose tissue is minimal in humans.

Another important role is the release of cholesterol from cholesterol esters for use in the production of steroids


Wikipedia

[ArchivalUser]

I know some of those Qs were not easy,and I think a small amount of exposure to them is beneficial.

Good job.
Thank you

[ArchivalUser]

thank u so much ,
we wii get benifit from this type of quetions