Free Bioenergetics MCQs with Answers
1,378 Bioenergetics MCQs from Biology, each with the correct answer and a written explanation of why it is correct. Free and unlimited, with no account needed.
Cellular respiration explains how cells release energy from glucose through glycolysis, the link reaction, Krebs cycle and electron transport chain. It includes ATP production, substrate-level and oxidative phosphorylation, aerobic versus anaerobic respiration, and the roles of mitochondria, oxygen and fermentation in energy transfer.
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Read the Bioenergetics notesFree MDCAT chapter notes with key terms1,378 questions · page 53 of 69
- A. Photometer
- B. Light meter
- C. Spectrometer
- D. Spectrophotometer
Explanation: A spectrophotometer is used to measure relative abilities of different pigments to absorb different wavelengths of light.
Correct answer: Spectrophotometer- A. Hydrophobic head of chlorophyll
- B. Hydrophilic tail of chlorophyll
- C. Hydrophobic tail of chlorophyll
- D. Hydrophilic head of chlorophyll
Explanation: The head of chlorophyll is hydrophilic but tail of chlorophyll is hydrophobic. Head consists of four pyrrole rings.
Correct answer: Hydrophilic head of chlorophyll- A. Four joined porphyrin rings
- B. Four Joined tetrapyrrole rings
- C. Four joined pyrrole rings
- D. Two joined pyrrole rings
Explanation: It is tetrapyrrole means four pyrrole rings, however collectively four pyrrole rings constitute a porphyrin.
Correct answer: Four joined pyrrole rings- A. Carbon of each pyrrole ring
- B. Hydrogen of each pyrrole ring
- C. Nitrogen of each pyrrole ring
- D. Methyl of each pyrrole ring
Explanation: An atom of magnesium is present in the centre of porphyrin ring and is coordinated with the nitrogen of each pyrrole ring.
Correct answer: Nitrogen of each pyrrole ring- A. α - chain
- B. β - chain
- C. Haem group
- D. Protein
Explanation: This is homology between hemoglobin and chlorophyll.
Correct answer: Haem group- A. Iron as central atom
- B. Magnesium as central atom
- C. Four pyrrole rings
- D. Central atom coordinated with nitrogen of each pyrrole ring
Explanation: Haem have iron as central atom whereas porphyrin of chlorophyll have magnesium as central atom.
Correct answer: Iron as central atom- A. Hydrocarbon tail
- B. Phytol
- C. Phytol or hydrocarbon tail
- D. Hydrophilic tail
Explanation: It is a hydrocarbon tail also called phytol.
Correct answer: Phytol or hydrocarbon tail- A. Atoms
- B. Elements
- C. Functional groups
- D. Carbon atoms
Explanation: It is methyl (CH3) for chl. a and carbonyl (CHO) for Chl. b.
Correct answer: Functional groups- A. Two more hydrogen atoms
- B. One less oxygen atom
- C. Two less hydrogen atoms and one more oxygen atom
- D. Two more hydrogen atom and one less oxygen atom
Explanation: Chlorophyll a and chlorophyll b differ from each other in only one of the functional groups bonded to the porphyrin; the methyl group…
Correct answer: Two less hydrogen atoms and one more oxygen atom- A. Two more hydrogen atoms
- B. One less oxygen atom
- C. Two less hydrogen atoms
- D. Two more hydrogen atom and one less oxygen atom
Explanation: Chlorophyll a have methyl group (-CH3) whereas chlorophyll b have carbonyl group (-CHO).
Correct answer: Two more hydrogen atom and one less oxygen atom1051. Due to slight difference in their _, the chlorophyll a and chlorophyll b show slightly different _.
- A. Structure, Absorption spectra
- B. Structure, Molecular formula
- C. Absorption spectra, Structure
- D. Absorption spectra, Molecular formula
Explanation: Option A is correct.Due to a slightly different chemical structure, the chlorophyll a and chlorophyll b show slightly different absorption…
Correct answer: Structure, Absorption spectra- A. Increase the range of light wavelengths being absorbed
- B. Decrease the range of light wavelengths being absorbed
- C. Have no effect on range of light wavelengths being absorbed
- D. Have no effects on the color of pigment
Explanation: Option A is correct.Yes, the difference in structure of different pigments can increase the range of light wavelengths being absorbed.
Correct answer: Increase the range of light wavelengths being absorbed- A. Carotenes
- B. Chlorophylls
- C. Xanthophylls
- D. All of these
Explanation: Yes, carotenoids,xanthophylls and chlorophylls are accessory pigments. Accessory pigments are pigments that are not directly involved in…
Correct answer: All of these- A. Blue part of spectrum
- B. Red part of spectrum
- C. Blue and Red parts of spectrum
- D. White and red part of spectrum
Explanation: Option C is correct.The absorption spectrum for chlorophyll indicates that absorption is maximum in the blue and red parts of the…
Correct answer: Blue and Red parts of spectrum- A. Two peaks
- B. Two peaks, one valley
- C. Two valleys
- D. One peaks, two valleys
Explanation: Option B is correct.An absorption spectrum of chlorophylls has two peaks and one valley.
Correct answer: Two peaks, one valley- A. Absorption spectrum of chlorophyll a
- B. Absorption spectrum of carotenoids
- C. Absorption spectrum of chlorophyll b
- D. All have broadest peaks
Explanation: Option D is correct.The absorption spectrum of chlorophyll a has two peaks and one valley.
Correct answer: All have broadest peaks- A. 430 - 670 nm
- B. 440 - 480 nm
- C. 460 - 640 nm
- D. 420 - 610 nm
Explanation: Option B is correct.The absorptive peaks in the absorption spectrum of chlorophyll b are almost at the wavelength of 450-475 nm.
Correct answer: 440 - 480 nm- A. Two phases
- B. Four phases
- C. Three phases
- D. Many phases
Explanation: Option A is correct.The reactions of photosynthesis consist of two phases, the light-dependent reactions and the Calvin…
Correct answer: Two phases- A. Dark reaction
- B. Light reaction
- C. Calvin cycle
- D. Oxidation phosphorylation
Explanation: Option B is correct.The reducing power and assimilatory power are synthesized during the light-dependent reactions of photosynthesis.
Correct answer: Light reaction- A. Enzymes
- B. Co-enzymes
- C. Energized electrons
- D. Both B and C
Explanation: Option B and C are correct.NADPH provides energized electrons for the synthesis of sugar by reducing CO2.
Correct answer: Both B and C