MDS PREP
The principal role of Vitamin E in the prevention of oxidative damage is to
1. oxidize metals to their less reactive state.
2. potentiate the action of superoxide dismutase.
3. reduce Vitamin C to its active oxidation state.
4. terminate free radical chain reactions in lipid bilayers.
Biochemistry
Answer: 2
The principal role of Vitamin E in the prevention of oxidative damage is to potentiate the action of superoxide dismutase
Which of the following enzymes is active in adipocytes following a heavy meal?
1) Glycogen phosphorylase
2) Glycerol kinase
3) Hormone-sensitive triacylglyceride lipase
4) Phosphatidate phosphatase
Biochemistry Answer: 4
The enzyme phosphatidate phosphatase converts phosphatidic acid to diacylglycerol during synthesis of triacylglycerides.
The function of adipose tissue is the storage of fatty acids as triacylglycerols in times of plenty and the release of fatty acids during times of fasting or starvation.
Fatty acids taken in by adipocytes are stored by esterification to glycerol-3-phosphate. Glycerol-3-phosphate is derived almost entirely from the glycolytic intermediate dihydroxyacetone phosphate through the action of glycerol-3-phosphate dehydrogenase. Glycolytic enzymes are active in adipocytes during triglyceride synthesis, but those of glycogen degradation (low levels in adipocytes) and gluconeogenesis (ie, glucose-6-phosphatase) are not.
Glycerol kinase is not present to any great extent in adipocytes, so that glycerol freed during lipolysis is not used to reesterify the fatty acids being released.
The enzyme triacylglyceride lipase is turned on by phosphorylation by a cyclic AMP-dependent protein kinase following epinephrine stimulation.
The immunoglobulin secreted in Bile is
1. IgG
2. 1gM
3. IgA
4. IgE
Biochemistry
Answer: 3
The immunoglobulin secreted in Bile is IgA
.Glucose can be synthesised from all of the following except
1. amino acids 2.Glycerol
3. Acetoacetate 4.Lactic acid
Biochemistry
Answer: 1
Glucose can be synthesised from Glyerol, Acetoacetate, Lactic acid
A component of the coenzyme required in a transamination process is
1. Thiamine
2 Folic acid
3 Pyridoxine
4 Riboflavin
Biochemistry
Answer: 3
A component of the coenzyme required in a transamination process is Pyridoxine
After fasting for 24 hours, the major source of glucose for the whole body is
1. amino acids from muscle protein degradation.
2. ketone bodies from muscle triglycerides.
3. glycogen stored in the muscle.
4. creatine phosphate
Biochemistry Answer: 4
Creatine Phosphate is the major source of glucose for the whole body during starvation
Aromatic amino acid is:
1. Tyrosine 2. Histidine
3. Arginine 4. Lysine
Biochemistry
Answer: 1
Tyrosine is Aromatic amino acid
Glutamate-pyruvate trans-aminase is predominantly present In:
1. Skeletal muscle
2. Cardiac muscle
3. Brain
4. Liver
Biochemistry
Answer: 4
Glutamate-pyruvate trans-aminase is predominantly present In Liver