Download 2- All essential amino acids are glucogenic. False

Protein sheet
‫ هذا النموذج من األسئلة هو مجرد استرشاد لنظام أسئلة االمتحان فى جزء البروتين يمكن‬:‫ملحوظة عامة‬
‫االستفادة منه عن طريق عمل تباديل لالسئلة من خالل األجوبة المطروحة‬
1- The free ammonia produced from glutamate by:
A.
Glutamate transaminase
B.
Glutamate synthetase
C.
Glutamate dehydrogenase √
2- The nitrogen atoms which form urea comes from:
A. Two ammonia molecules
B. Ammonia and aspartate √
C. Ammonia and glutamate
3- Transamination is the transfer of an amino group
A. from a carboxylic acid to ammonia
B.
from an amino acid to α- keto acid √
C. from α- keto acid to amino acid
4- Lysine is degraded to acetoacetyl CoA and is described as a
A. ketogenic amino acid √
B. glucogenic amino acid
C. keto-gluco amino acid
5- A ketogenic amino acid is one which degrades to
A. either acetyl CoA or acetoacetyl CoA √
B. pyruvate or citric acid cycle intermediates
C. multiple intermediates including pyruvate or citric acid cycle intermediates
and acetyl CoA or acetoacetyl CoA
6- Carbamoyl Phosphate adds with Ornithine to form
A. Citrulline √
B. Arginine
C. Aspartate
7- The cofactor required for phenyl alanine hydroxylase reaction is:
A. Tetrahydrofolate
B. Ascorbate
C. Tetrahydrobiopterin √
8- Urea is synthetized in:
A. Cytoplasm
B. Mitochondria
C. Both cytoplasm and mitochondria√
9- In mammalian cells, serine is a precursor of which amino acid:
A. Methionine
B. Glycine √
C. Arginine
10- What is the product P in the following reaction?
α-ketoglutarate + alanine → pyruvate + P
A. Glutamate √
B. Glutamine
C. Aspartate
11- Which of the following amino acid is produced from phenylalanine?
A. Tryptophan
B. Leucine
C. Tyrosine √
12- Which two non-essential amino acids can be synthesized from glutamate?
A. Alanine and arginine
B. Arginine and proline √
C. Tyrosine and phenylalanine
13- Amidation of aspartate yields:
A. Glutamine
B. Asparagine √
C. Glutamate
14-
3-phosphoglycerate can be used to synthesize which amino acid?
A. Serine √
B. Glutamine
C. Tyrosine
15- In most of reactions the methyl group carrier and donor is:
A. SAM √
B. THF
C. BH4
Use the following Urea Cycle diagram to answer this
question. Which compound is derived from a
condensation of ornithine and compound E? Draw the
structure of either of: ornithine, compound E or the
resulted product.
The product is compound A which is citrulline
The structure of ornithine is:
The structure of compound E (Carbamoyl phosphate):
The structure of citrulline is:
True or False with explanation:
1- An increase in gluconeogenesis from amino acids results in a
decrease in urea formation.
False
An increase in the availability of gluconeogenic amino acids from
the catabolism of body protein is associated with increased
ammonia and results in increased urea production.
2- All essential amino acids are glucogenic.
False
The essential amino acids leucine and lysine are ketogenic.
3- Ornithine and citrulline are found in tissue proteins.
False
Ornithine and citrulline are amino acids that are intermediates in
the urea cycle, but are not found in tissue proteins because there are
no codons for them.
4- Cysteine is an essential amino acid in individuals consuming
a diet severely limited in methionine.
True
Methionine is the precursor of cysteine.
5- In the presence of adequate dietary sources of tyrosine,
phenylalanine is not an essential amino acid.
False
Phenylalanine is essential regardless of the level of tyrosine.