Exam(s) MCQ Deck

Question 1

In coordination chemistry the donor atom of a ligand is___________

Answer 1

the atom in the ligand that shares an electron pair with the metal

Question 2

The biological functions of carbonic anhydrase and alcohol dehydrogenase, respectively are__________.

Answer 2

Hydration of CO2 to bicarbonates, alcohols, and aldehydes

Question 3

The active sites of carboxypeptidase A contain _______ and catalyze ________ .

Answer 3

Zn(II); the hydrolysis peptide bonds

Question 4

Which of the following represents the correct set of essential elements?

Answer 4

Fe, Na, K, Zn

Question 5

The amino acid side chain with high affinity for Ca2+ and Cu2+ in metallo-proteins is __________.

Answer 5

Carboxylate from glutamate for Ca2+ and imidazole from histidine for Cu2+

Question 6

Which biologically active species control important cellular processes such as hydrolysis?

Answer 6

Metallo-proteins

Question 7

How is acid-base catalysis accomplished in biological processes?

Answer 7

Through metal ion built-in protein structures

Question 8

The magnesium-containing 1,5-biphosphate enzyme (ribusco enzyme) is of great interest because_________.

Answer 8

It removes CO2 gas in the atmosphere and fixing it into other products

Question 9

What are Arginases?

Answer 9

Arginases are Mn(II) containing metalloenzymes that catalyze the hydrolysis of nitrogen-containing proteins to produce urea as the byproduct.

Question 10

Zinc finger motifs are particular characteristics of proteins that function as

Answer 10

Gene regulators

Question 11

Metallothioneins are _________

Answer 11

cysteine-containing ligands that bind mainly soft metal ions

Question 12

In biological systems, the metal ion involved in O2 transport besides Fe is___________.

Answer 12

Cu (copper)

Question 13

Which biomolecules are prone to the irreversible oxidative damage caused by reactive oxygen species (ROS)_________.

Answer 13

DNA, Lipids, Proteins, Carbohydrates

Question 14

The number of O2 molecules that hemoglobin can transport is ___________.

Answer 14

Four

Question 15

The amino acid side chains that act as ligands for the binding of Fe3+ in transferrin are ___________.

Answer 15

Tyrosine, histidine, and aspartate

Question 16

Which one of the following is not the direct reduction products of O2, which are commonly known as reactive oxygen species (ROS)___________?

Answer 16

O3

Question 17

The ligand system found in hemoglobin and myoglobin is__________.

Answer 17

Porphyrin

Question 18

The biological function of Myoglobin is___________.

Answer 18

None of the above
Myoglobin stores oxygen!

Question 19

The proteins which act as oxygen transport in small organisms are __________.

Answer 19

Hemocyanin and hemerythrin

Question 20

Which one of the following is NOT the essential function of calcium in biological systems?

Answer 20

Transport of dioxygen
Important Functions: Nerve signaling, enzyme catalysis, structural support in proteins, muscle movement

Question 21

The toxic exposure of children to mercury and cadmium contamination is treated by chelation therapy mainly using amino acid ligands that contain ________ residue

Answer 21

Cysteine

Question 22

Iron-Sulfur clusters in biological systems are involved in__________.

Answer 22

Electron transfer

Question 23

Superoxide dismutase contains the metal ions________.

Answer 23

Cu(II) and Zn(II)

Question 24

A well-known naturally occuring organometallic compound is________

Answer 24

Vitamin B12 coenzyme

Question 25

The main biological function of cytochrome-c oxidase is __________.

Answer 25

Reduction of O2 to water

Question 26

Cytochrome-C is __________.

Answer 26

Heme protein

Question 27

What is the molecular basis of the mode of action for Pt(II) chemotherapy agents?

Answer 27

Formation of a stable complex between DNA and Pt(II) resulting in the bending of DNA helix and partial unwinding

Question 28

The active site of oxygen atom transfer enzymes contain________.

Answer 28

Mo (molybdenum)

Question 29

Which one of the following complex/s shows activity against cancerous cells?

Answer 29

All complexes are active agents