Term 1: Week 4 - Amino Acids (Instructor Handout)

What is the molecular weight of Glycine? A. 75 g•mol−1 B. 80 g•mol−1 C. 90 g•mol−1 D. 95 g•mol−1

A 75 g•mol−1

What is the maximum wavelength that Tryptophan and tyrosine absorb? A. 280nm B. 260nm C. 257nm D. 230nm

A. 280nm

1. What is the composition of hemoglobin A. A-alpha-beta, A2 alpha delta, F alpha gamma B. A-alpha-beta, A2 alpha, F gamma C. A-alpha, A2 delta, F alpha gamma D. A-alpha-beta, A2 delta, F alpha

A. A-alpha-beta, A2 alpha-delta, F alpha-gamma

he two amino acids having R groups with a negative net charge at pH 7.0 are A. Aspartate and glutamate B. Arginine and histidine C. Cysteine and methionine D. Proline and valine

A. Aspartate and glutamate

Which of the following amino acid is sweet in taste? A. Glycine B. Alanine C. Glutamic acid D. None of these

A. Glycine

Which among the following is both glucogenic and ketogenic? A. Isoleucine B. Leucine C. Lysine D. Histidine

A. Isoleucine

Which of these are used to measure optical activity? A. Polarimeter B. Planometer C. Psychrometer D. Photometer

A. Polarimeter

Which of the following is an example of a bioplastic? A. Polyaspartate B. Polyglutamate C. Poly-L-lysine D. All of these

A. Polyaspartate

Which of the following amino acid will be absent in the α (alpha) helix structure of a protein? A. Proline B. Glycine C. Galine D. Glutamic acid

A. Proline

Which of the following is not an essential amino acid? A. Proline B. Histidine C. Leucine D. Methionine

A. Proline

Which among the following is a non-essential amino acid? A. Serine B. Threonine C. Lysine D. Histidine

A. Serine

What is this type of molecule (amino acid at physiological pH) called? A. Zwitterion B. Leucine C. Glycine D. Histidine

A. Zwitterion

Acidic side chains can act as a: A. proton donors B. proton acceptors C. protein donors D. protein acceptors

A. proton donors

Which amino acid can form disulfide bonds? A. Lysine B. Cysteine C. Proline D. Alanine

B. Cysteine

Which is the smallest amino acid? A. Isoleucine B. Histidine C. Leucine D. Glycine

D. Glycine

Which of these amino acids are not optically active? A. Cysteine B. Lysine C. Arginine D. Glycine

D. Glycine

Histones are rich in__________. A. Lysine B. Arginine C. Histidine D. Lysine and Arginine

D. Lysine and Arginine

Which of the following is an essential amino acid? A. Cysteine B. Asparagine C. Glutamine D. Phenylalanine

D. Phenylalanine

How many different amino acids are found in mammalian cells? A. 20 B. 30 C. 40 D. 50

A. 20

Identify the amino acids containing nonpolar, aliphatic R groups A. Phenylalanine, tyrosine, and tryptophan B. Glycine, alanine, leucine C. Lysine, arginine, histidine D. Serine, threonine, cysteine

B. Glycine, alanine, leucine

How is the secondary structure of a protein stabilized? A. Van der wall forces B. Hydrogen bonding C. Covalent bond D. Hydrophobic bond

B. Hydrogen bonding

What are the amino group and the carboxyl group (that are attached to the alpha-carbon) charges at physiological pH? A. NH2+ and COO- B. NH3+ and COO- C. NH+ and COO- C. NH3+ and COO+

B. NH3+ and COO-

Bacteria prefer to use the codon CGA instead of AGA to code for Arginine. This is an example for _____. A. Second genetic code B. Nullomers C. Transcriptional decoding D. Allomers

B. Nullomers

Which of the following amino acid act as excitatory neurotransmitter? A. Glutamate B. Aspartate C. Cysteine D. All of these

D. All of these

Which of the following amino acids act as an inhibitory neurotransmitter? A. Glycine B. Alanine C. GABA D. All of these

D. All of these

Which of the following is a true statement? A. Tryptophan and tyrosine are significantly more polar than phenylalanine B. Leucine is commonly used as an ingredient in the buffers of the SDS page C. Aspartate is an essential amino acid D. Lysine is a non-essential amino acid

A. Tryptophan and tyrosine are significantly more polar than phenylalanine

What does it mean that amino acid is chiral? A. When a carbon atom has four different constituents. B. When a carbon atom has six different constituents. C. When a carbon atom has eight different constituents. D. When a carbon atom has ten different constituents.

A. When a carbon atom has four different constituents.

Amino acids can be classified into four general groups based on the properties of the "R" group in each amino acid. Amino acids can be: A. polar, nonpolar, negatively charged, or negatively charged. B. polar, nonpolar, positively charged, or negatively charged. C. polar, positively charged, or negatively charged. D. nonpolar, positively charged, or negatively charged.

B. polar, nonpolar, positively charged, or negatively charged.

Basic side chains can act as a: A. proton donors B. proton acceptors C. protein donors D. protein acceptors

B. proton acceptors

What different roles can amino acids have? A. Fuel B. Conversion to other molecules building blocks of proteins C. All of the Above D. None of the Above

C. All of the Above

The amino acid is commonly used as an ingredient in the buffers of SDS PAGE. A. Aspartic acid B. Glutamic acid C. Glycine D. Aspartic acid and Lysine together

C. Glycine

In which amino acid Imidazole group, is an aromatic ring found? A. Lysine B. Arginine C. Histidine D. Glutamate

C. Histidine

The general structure of all amino acids are same except for ___________ A. Lysine B. Glycine C. Proline D. Alanine

C. Proline

Which amino acid differs from the others by carrying an imino group and causes kinks in the polypeptide chain? A. Lysine B. Glycine C. Proline D. Alanine

C. Proline

Which of the following is an imino acid? A. Alanine B. Glycine C. Proline D. Serine

C. Proline

Among the 20 standard proteins coding amino acids, which one is least occurs in proteins? A. Glycine B. Alanine C. Tryptophan D. Methionine

C. Tryptophan

Which of these are rare amino acids in a protein? A. Leucine and serine B. Lysine and glutamic acid C. Tryptophan and methionine D. Leucine and lysine

C. Tryptophan and methionine

What is the basic structure of an amino acid? A. beta carbon, carboxyl group, amino group, oxygen, side chain (R) B. alpha carbon, carboxyl group, amino group, oxygen, side chain (P) C. alpha carbon/carboxyl group/amino group/hydrogen/side chain (R) D. alpha carbon/carboxyl group/amino group/hydrogen/side chain (P)

C. alpha carbon/carboxyl group/amino group/hydrogen/side chain (R)

How are amino acids acquired? (3 possibilities) A. Made in the body B. Made from other aa C. Acquired through diet D. All of the above E. none of the above

D. All of the above

Which amino acid act as the precursor of nucleotide biosynthesis? A. Aspartate B. Glycine C. Glutamine D. All of these

D. All of these

What is the characteristic of alpha-carbon? A. The carbon is alpha because it is equal to the carboxyl group. B. The carbon is alpha because it is the same as the carboxyl group. C. The carbon is alpha because it is adjacent to the carboxyl group. D. The carbon is alpha because it is opposite to the carboxyl group.

D. The carbon is alpha because it is adjacent to the carboxyl group. It determines whether the aa is in L or D form.

What is a desmosine bond? A. positional isomer that crosslinks tropoelastin fibers within elastin B. a protein that is abundant in the lung. C. Polar amino acids have "R" groups that are hydrophilic, meaning that they seek contact with aqueous solutions. D. no positional isomer that crossings tropoelastin fibers within elastin E. A, B, C F. B, C, D

E. A, B, C

Name 4 characteristics of elastin: A. 700 aa long polypeptide-tropoelastin B. Proline, lysine rich C. Desmosine bonds D) Cross links between side chains gives connective tissue its elasticity E. All of the Above F. None of the Above

E. All of the Above

Name 4 characteristics of collagen: A. Triple stranded helix B. Held together by hydrogen bonds C. Hydroxyproline, hydroxylysine, proline and glycine common aa, D. despite common basic structure many different forms and functions in the body-can be divided into fibril forming, network forming, fibril associated. E. all of the above F. none of the above

E. all of the above

Where are polar vs. non-polar amino acids found: - in a nonsoluble protein polar on the surface of the protein True or False

False - in a soluble protein polar on the surface of the protein

Mutation of the CF gene. Many have been described BUT 60% of cases share the same mutation at position 408 deleting one aa and leading to the complete absence of the ion transporter the gene encodes for causes the problems associated with cystic fibrosis. True or False

False, Mutation of the CF gene. Many have been described BUT 70% of cases share the same mutation at position 508 deleting one aa and leading to the complete absence of the ion transporter the gene encodes for causes the problems associated with cystic fibrosis.

Mutations in the genes involved in the alpha hemoglobin subunit causes the problems associated with beta-thalassemia. True or False

False, Mutations in the genes involved in the beta hemoglobin subunit causes the problems associated with beta-thalassemia.

Scurvy is associated with collagen malformation because Vitamin E is necessary for hydroxylation of proline and lysine. True or False

False, scurvy is associated with collagen malformation because Vitamin C is necessary for hydroxylation of proline and lysine.

Three amino acids and what other molecules they can be converted into: -Tyrosine -Tryptophan -Leucine True or False

False: -Tyrosine -Tryptophan -Histidine

A one aa substitution gluàval in the beta hemoglobin subunit causes the problems associated with sickle cell disease. True or False

True

A variety of mutations in the genes encoding alpha hemoglobin causes the problems associated with alpha thalassemia. Severity depends on how many alpha genes that are affected causes the problems associated with alpha thalassemia. True or False

True

Anemia associated with Thalassemia. The RBC are defective and phagocytosed faster than new cells can be produced. True or False

True

Name diseases associated with loss of collagen: brittle bone disease, Ehler-Danlos. True or False

True

Name the 3 groups of collagen types: fibril forming, network forming, fibril associated True or False

True

Name the 9 essential amino acids: histidine, isoleucine, leucine, lysine, methionine, valine, phenylalanine, threonine, tryptophan True or False

True

No Answer - Discussion (Check - True) - All answers are true. Name 7 Characteristics of an Amino Acid -Amino acids are basic units of protein. -All amino acids have at least one acidic carboxylic acid (-COOH) group and one basic amino (-NH2) group. -Amino acids are colorless, crystalline solid -They are soluble in water and insoluble in an organic solvent Only the L-Form of amino acids is found in Proteins in the human body. -If D-Form is present, it is converted into L-form by enzymes in the liver. -More than 300 amino acids are found in nature but only 20 amino acids are standard and present in protein because they are coded by genes. -Other non-standard amino acids are modified amino acids and called non-protein amino acids. True or False

True

Proteins can either be synthesized by free ribosomes in the cytoplasm or by ribosomes stuck to the ER. True or False

True

The Henderson-Hasselbalch equation applies to amino acids because: -the acid-base properties of basic structure and of side chains -the charges/dissociation on amino and carboxyl groups -the side chains will differ depending on the surrounding pH and the pKa for each group. True or False

True

The theory behind the fact that sickle cell disease more commonly affects individuals of African descent is because cells with sickle hemoglobin are phagocytosed faster, the RBC life span is not long enough for the Malaria parasite Plasmodium falciparum to complete the human part of its reproduction cycle, so it is protective against Malaria to carry sickle cell trait. True or False

True