DHN 311 EXAM 3 EXAM COMPLETE
QUESTIONS AND CORRECT DETAILED
ANSWERS (VERIFIED ANSWERS)
Describe two different functions of the pentose phosphate pathway (PPP) (e.g.
synthesis of molecules for other pathways, events). - Answer -1. it generates NADPH
2. it generates ribose 5-phosphate
Why would the PPP be important in rapidly dividing cells? - Answer -Because ribose is
needed in nucleic acid synthesis and the PPP produces ribose
Pentose phosphate pathway (PPP) occurs in the ____ of the cell. - Answer -cytosol
The major catabolic fate of most of the ______ in a cell ends up in cellular respiration,
but the PPP is another fate. - Answer -glucose 6-phosphate
what are some of the things the PPP generates? - Answer -1. metabolites used in
glycolysis
2. precursors for nucleotide synthesis
3. nucleic acids
4. fatty acids
5. antioxidants
Glucose is the preferred energy source of the _____ and necessary for red blood cells
which have no _____ - Answer -brain
mitochondria
Three sources of blood glucose include what 3 things - Answer -1. diet
2. degradation of glucose
3. gluconeogenesis
what sources does the body get cholesterol from? - Answer -1. diet
2. denovo synthesis
how is cholesterol made? - Answer -cholesterol is synthesized from acetyl CoA
what is the rate limiting enzyme in the production of cholesterol? - Answer -the rate
limiting enzyme is HMG CoA reductase
How is cholesterol synthesis regulated? - Answer -as total body cholesterol increases,
synthesis rate decreases
, How is cholesterol synthesis regulated hormonally? - Answer -the activity of the HMG
CoA reductase is controlled hormonally. it increases with insulin and decreases with
glucagon
the activity of HMG CoA reductase increases with ____ and decreases with ___ -
Answer -insulin
glucagon
How does negative feedback regulate cholesterol synthesis primarily in the liver? -
Answer -cholesterol synthesis is regulated by negative feedback because the synthesis
is suppressed by dietary cholesterol in the LIVER
The starting molecule used to generate cholesterol (denovo synthesis) is _____which
will eventually form Beta-hydroxy-beta-methylglutaryl-CoA (_____) after several
enzymatic steps. - Answer -acetyl CoA
HMG CoA
One source of the acetyl CoA that is used to make cholesterol was from excess _____
that was converted to acetyl CoA. - Answer -glucose
Cholesterol is made in nearly all tissues of the body with a good bit of it being generated
by the ____. - Answer -liver
Cholesterol is derived from two sources, de novo synthesis and _____. - Answer -diet
Humans do not need to eat dietary cholesterol because..... - Answer -our tissues can
make enough to meet our bodies needs
the balance in cholesterol influx and efflux do not always balance which leads to
deposition of cholesterol in the ______ ______ of blood vessels . - Answer -endothelial
lining
Cholesterol falls under the classification of _____ because it is a very _____ compound
that consists of four fused carbon rings (A-D), which contain many _____. - Answer -
lipids
hydrophobic
carbons
Cholesterol esters have a _____ _____ attached to the third carbon of ring A. - Answer
-fatty acid
Adding the fatty acid to cholesterol makes the cholesterol molecule... - Answer -.....more
hydrophobic than non-esterified cholesterol
________ is the major enzyme control point for cholesterol biosynthesis. - Answer -
HMG CoA reductase
QUESTIONS AND CORRECT DETAILED
ANSWERS (VERIFIED ANSWERS)
Describe two different functions of the pentose phosphate pathway (PPP) (e.g.
synthesis of molecules for other pathways, events). - Answer -1. it generates NADPH
2. it generates ribose 5-phosphate
Why would the PPP be important in rapidly dividing cells? - Answer -Because ribose is
needed in nucleic acid synthesis and the PPP produces ribose
Pentose phosphate pathway (PPP) occurs in the ____ of the cell. - Answer -cytosol
The major catabolic fate of most of the ______ in a cell ends up in cellular respiration,
but the PPP is another fate. - Answer -glucose 6-phosphate
what are some of the things the PPP generates? - Answer -1. metabolites used in
glycolysis
2. precursors for nucleotide synthesis
3. nucleic acids
4. fatty acids
5. antioxidants
Glucose is the preferred energy source of the _____ and necessary for red blood cells
which have no _____ - Answer -brain
mitochondria
Three sources of blood glucose include what 3 things - Answer -1. diet
2. degradation of glucose
3. gluconeogenesis
what sources does the body get cholesterol from? - Answer -1. diet
2. denovo synthesis
how is cholesterol made? - Answer -cholesterol is synthesized from acetyl CoA
what is the rate limiting enzyme in the production of cholesterol? - Answer -the rate
limiting enzyme is HMG CoA reductase
How is cholesterol synthesis regulated? - Answer -as total body cholesterol increases,
synthesis rate decreases
, How is cholesterol synthesis regulated hormonally? - Answer -the activity of the HMG
CoA reductase is controlled hormonally. it increases with insulin and decreases with
glucagon
the activity of HMG CoA reductase increases with ____ and decreases with ___ -
Answer -insulin
glucagon
How does negative feedback regulate cholesterol synthesis primarily in the liver? -
Answer -cholesterol synthesis is regulated by negative feedback because the synthesis
is suppressed by dietary cholesterol in the LIVER
The starting molecule used to generate cholesterol (denovo synthesis) is _____which
will eventually form Beta-hydroxy-beta-methylglutaryl-CoA (_____) after several
enzymatic steps. - Answer -acetyl CoA
HMG CoA
One source of the acetyl CoA that is used to make cholesterol was from excess _____
that was converted to acetyl CoA. - Answer -glucose
Cholesterol is made in nearly all tissues of the body with a good bit of it being generated
by the ____. - Answer -liver
Cholesterol is derived from two sources, de novo synthesis and _____. - Answer -diet
Humans do not need to eat dietary cholesterol because..... - Answer -our tissues can
make enough to meet our bodies needs
the balance in cholesterol influx and efflux do not always balance which leads to
deposition of cholesterol in the ______ ______ of blood vessels . - Answer -endothelial
lining
Cholesterol falls under the classification of _____ because it is a very _____ compound
that consists of four fused carbon rings (A-D), which contain many _____. - Answer -
lipids
hydrophobic
carbons
Cholesterol esters have a _____ _____ attached to the third carbon of ring A. - Answer
-fatty acid
Adding the fatty acid to cholesterol makes the cholesterol molecule... - Answer -.....more
hydrophobic than non-esterified cholesterol
________ is the major enzyme control point for cholesterol biosynthesis. - Answer -
HMG CoA reductase
