All Free Biology MCQs with Answers
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19844 questions · page 668 of 1985
6671. What is the correct location of ATP synthase in mitochondria?
- A. Mitochondrial matrix
- B. Inner mitochondrial membrane
- C. Outer mitochondrial membrane
- D. Inter-membrane space
Explanation: F1 particles are located on cristae, the infoldings of the inner mitochondrial membrane. F1 particle are usually ATP synthases which play an important role in the synthesis of ATP through chemiosmosis.
Correct answer: Inner mitochondrial membrane6672. Which of the following structures is involved in oxidative phosphorylation?
- A. Inner mitochondrial membrane
- B. Mitochondrial matrix
- C. Outer mitochondrial membrane
- D. Thylakoid membrane
Explanation: Electron transport chain (ETC) occurs on inner mitochondrial membrane which provides the site for pumping of protons across it. Oxidative phosphorylation is associated with ETC.
Correct answer: Inner mitochondrial membrane6673. Which of the following eukaryotic organelles has a symbiotic origin with bacteria?
- A. Endoplasmic reticulum
- B. Chloroplast
- C. Lysosomes
- D. Golgi apparatus
Explanation: Both chloroplasts and mitochondria are thought to be originated from prokaryotes and are explained with the help of the endosymbiotic hypothesis.
Correct answer: Chloroplast6674. Chlorophyll molecule resembles:
- A. Carotenoids
- B. Xanthophylls
- C. Globin chains of haemoglobin
- D. The haem part of haemoglobin
Explanation: Chlorophyll molecule reselmbles haem group of heamoglobin. The only difference between chlorophyll and haemoglobin is that chlorophyll has Mg+2 while haem has Fe+2 as the central atom.
Correct answer: The haem part of haemoglobin6675. Which of the following organelle has a continuous connection with the nuclear membrane?
- A. Golgi apparatus
- B. Lysosomes
- C. RER
- D. SER
Explanation: The RER has a continous connection with the nuclear membrane.
Correct answer: RER6676. What is the function of the nucleolus?
- A. Formation and breakdown of nuclear envelope
- B. Formation of centromere
- C. Formation of ribosomes
- D. Organization of spindle during nuclear division
Explanation: Nucleolus is the darkly stained area within the nucleus and without any membranous boundary to separate it from the rest of the nuclear material. These are said to be the factory of ribosomes while ribosomes are said to be the factory of protein synthesis.
Correct answer: Formation of ribosomes6677. Which of the following has 40 chromosomes?
- A. Corn
- B. Sugarcane
- C. Frog
- D. Mouse
Explanation: Mouses, corns, sugarcanes and frogs have 40, 20, 80 and 26 chromosomes in their diploid cells, respectively.
Correct answer: Mouse6678. A group of ribosomes attached to messenger RNA is known as a?
- A. Ribosome
- B. Lysosome
- C. Nucleosome
- D. Polysome
Explanation: A polysome is a cluster of ribosomes held together by a strand of messenger RNA which each is translating.
Correct answer: Polysome6679. What is the wall strenghtening material in the prokaryotic cell wall?
- A. Cellulose
- B. Silica
- C. Chitin
- D. Peptidoglycan
Explanation: Bacterial cell wall is composed of peptidoglycan also called murein, which is made from polysaccharide chains cross-linked by short peptides. Bacterial cell walls are different from the cell walls of plants and fungi which are made of cellulose and chitin, respectively.
Correct answer: Peptidoglycan6680. The interior of the chloroplast is divided into a heterogeneous structure, embedded in the matrix. This structure is known as?
- A. Grana
- B. Stroma
- C. Thylakoids
- D. Cisternae
Explanation: Thylakoids are flattened vesicles which arrange themselves in the form of grana and inter-granum. Grana are piled up in the form of coins.
Correct answer: Grana