Tag: bio-chemistry

Quizzes (82) Questions (1918)

Questions Related to bio-chemistry

Multiple choice bio-chemistry carbohydrate metabolism energy output living organisms and energy production respiration in cell

In prokaryotic cells, the number of ATP generated form one glucose molecule is _______

  1. $36$
  2. $38$
  3. $34$
  4. $32$
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

In the eukaryotic ell, the aerobic respiration occurs in mitochondria as well as the cytoplasm. The Electron Transport Chain (ETC) that yields the maximum ATPs is located in the inner membrane of the mitochondria. So, the NADH made during the glycolysis in cytoplasm have to be transferred to the mitochondria using the shuttle system and for this, 2 ATPs are consumed. However, in the bacterial cell, since there is no mitochondria, the whole process of respiration occurs within the cytoplasm so no ATP is consumed in transporting across the organelle. Therefore, 38 ATPs are made form one glucose in bacteria while 36 are made in an eukaryotic cell.

Hence, the correct answer is '38'

Multiple choice bio-chemistry carbohydrate metabolism energy output living organisms and energy production respiration in cell

Energy released by oxidation of one molecule of glucose is -

  1. 800 K.cal

  2. 695 K. cal

  3. 686 K.cal

  4. 700 K.cal
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

When 1 mol (180 g) of glucose reacts with oxygen under standard conditions, 686 kcal of energy is released. 36 ATP synthesised in aerobic respiration. Total free energy stored as high energy phosphate bonds in ATP is therefore 252kcal. The remaining energy is lost. So, the correct option is '686 K.cal'.


Multiple choice bio-chemistry carbohydrate metabolism energy output living organisms and energy production respiration in cell

The energy stored in one molecule of NADPH and one molecule of ATP are ....... and ...... respectively.

  1. 52 kcal, 7 kcal

  2. 520 kcal, 70 kcal

  3. 150 kcal, 22 kcal

  4. 650 kcal, 90 kcal
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

Nicotinamide adenine dinucleotide phosphate is abbreviated as NADP, is a cofactor used in anabolic reactions, such as lipid and nucleic acid synthesis, which require NADPH as a reducing agent. It produces 52 kCal of energy from one molecule. Adenosine triphosphate used in cells as a energy currency, often called the molecular unit of currency of intracellular energy transfer. ATP is therefore continuously recycled in organisms: the human body, which on average contains only 250 grams of ATP.  One molecule of ATP produces 7kCal of energy.

Multiple choice bio-chemistry carbohydrate metabolism energy output living organisms and energy production respiration in cell

How many ATP are synthesized per sucrose molecule(gross synthesis) in aerobic respiration through substrate level phosphorylation?

  1. $10$
  2. $12$
  3. $30$
  4. $76$
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

C- In substrate-level phosphorylation, 2 ATP are synthesized from glycolysis and 2 ATP from Krebs cycle Oxidative phosphorylation that is, 2 × 1.5 ATP or 2 × 2.5 ATP (in malate-aspartate shuttle). Thereby, from the oxidative decarboxylation of pyruvate there shall be 2 NADH+H+ and 6 from Krebs cycle making it – (a) 8 × 2.5 ATP & 2 FADH2 from the Krebs cycle, (b) 2 × 1.5 ATP; thus summing it up to 4 + 3 (or 5) + 20 + 3 = 30 (or 32) ATP per molecule of glucose.

Multiple choice bio-chemistry carbohydrate metabolism energy output living organisms and energy production respiration in cell

The radiant energy is stored in the form of chemical energy in

  1. NADP

  2. Stored food

  3. RNA

  4. DNA
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

Photosynthesis is an energy conversion process. During photosynthesis green plants trap solar energy and synthesize sugars. Thus light energy present in photons is converted to chemical energy, which is trapped in the bonds of sugar molecules.

Multiple choice bio-chemistry carbohydrate metabolism energy output living organisms and energy production respiration in cell

Complete oxidation of 1 gm mol of glucose gives rise to ................. calories.

  1. 6860000

  2. 686000

  3. 68600

  4. 6860

Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

At pH 7.0 and temperature 298 K, the standard free energy change of oxidation of glucose is -686 Kilocalories per mole or -2840 Kilojoules per mole. The negative values indicate that oxidation of glucose is an exergonic or energy releasing process.

Multiple choice bio-chemistry carbohydrate metabolism energy output living organisms and energy production respiration in cell

Common immediate source of energy for cellular activity is

  1. Glucose.

  2. Aldohexose.

  3. ATP.

  4. NAD.
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

Adenosine triphosphate (ATP) is a nucleotide with three phosphates. It is the universal energy currency for all cellular metabolic processes. Endergonic processes are driven by energy input using hydrolysis of ATP. Exergonic processes are coupled to ATP synthesis. 

Multiple choice bio-chemistry carbohydrate metabolism energy output living organisms and energy production respiration in cell

What is the energy coin of a cell?

  1. DNA

  2. RNA

  3. ATP

  4. Minerals
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation
  • During cellular metabolism, energy is frequently exchanged between endergonic and exergonic reactions and molecules.
  • The ATP is a universal energy currency, which is used in these cellular energy exchanges.
  • The reason has been that is ATP can be formed easily by the process of phosphorylation of ADP as suggested by the chemiosmotic theory.
  • Further, one molecule of ATP has two terminal high energy acid anhydride bonds, which can break easily to provide energy. 
  • Therefore, ATP can be both formed easily as well as broken easily. 

    Hence, correct option is C.