BIOL 1010 Biology 1 Molecular and Cellular Systems TERM TEST

BIOL 1010 Biology 1: Molecular and Cellular Systems TERM TEST 2 QUESTION BOOKLET Multiple Choice Questions (50 questions) Answer all 50 questions Read all questions carefully Choose the one best answer for each of the following questions. Mark answer in Question Booklet (as insurance in case of damaged scantron ONLY! Mark the appropriate letter on your Scantron IN PENCIL. Only answers recorded on the Scantron will be marked! 1. How is the ATP made during glycolysis generated? A. By substrate-level phosphorylation B. By electron transport C. By photophosphorylation D. By chemiosmosis E. By the reduction of NAD to NADH H 2. How many reduced dinucleotides would be produced with four turns of the citric acid cycle? A. 1 FAD and 4 NAD B. 4 FAD and 12 NAD C. 2 FADH2 and 8 NADH H D. 4 FADH2 and 12 NADH H* E. 1 FADH2 and 4 NADH H 3. As a research scientist, you measure the amount of ATP and NADPH H consumed by the Calvin Cycle in 1 hour. You find 30,000 molecules of ATP consumed, but only 20,000 molecules of NADPH. Where did the extra ATP molecules come from? A. photosystem B. non-cyclic electron flow C. chlorophyl D. cyclic electron flow E. photosystem II

Solution

Ans 1: Glycolysis is the metabolic pathway that converts glucose C₆H₁₂O₆, into pyruvate, CH₃COCOO + H⁺. The free energy released in this process is used to form the high-energy molecules ATP (adenosine triphosphate) and NADH (reduced nicotinamide adenine dinucleotide).Therefore ATP is generated by reduction of NAD+ to NADH + H+.

Ans 2: One complete cycle of Kreb cycle or citric acid cycle generate wo molecules of carbon dioxide, one guanosine triphosphate molecule (GTP), and enough electrons to generate three molecules of NADH and one molecule of FADH2. so four turn of citric acid cycle generate 4 FADH2 and 12 NADH+H+.

Ans 3: Three turns of the Calvin cycle are needed to make one G3P molecule that can exit the cycle and go towards making glucose. Let’s summarize the quantities of key molecules that enter and exit the Calvin cycle as one net G3P is made. In three turns of the Calvin cycle:

Carbon. 3 Co2 combine with 3 RuBP acceptors, making 6 molecules of glyceraldehyde-3-phosphate (G3P).

1 G3P molecule exits the cycle and goes towards making glucose.

5 G3P molecules are recycled, regenerating 3 RuBP acceptor molecules.

ATP. 9 ATP are converted to 9 ADP (6 during the fixation step, 3 during the regeneration step).

NADPH. 6 NADPH are converted to 6 NADP+ + start superscript, plus, end superscript (during the fixation step).

A G3P molecule contains three fixed carbon atoms, so it takes two G3Ps to build a six-carbon glucose molecule. It would take six turns of the cycle, or 6CO2t, 18ATP, and 12 NADPH, to produce one molecule of glucose. so, Photosystem-II generate extra ATP which is light dependant rection center present in thylakoid membrane.