All Free Biology MCQs with Answers
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19844 questions · page 680 of 1985
6791. The peptidoglycan cell wall is present in:
- A. Penicillium
- B. Adiantum
- C. Bacterium
- D. Polytrichum
Explanation: Option C is correct because bacterium has a cell wall and is made of peptidoglycan.
Correct answer: Bacterium6792. Which of the following function is not performed by the cell membrane of a plant cell?
- A. Regulation of material
- B. Active transport
- C. Recognition of substances outside the material
- D. Phagocytosis
Explanation: In phagocytosis, specialized cells called phagocytes, such as macrophages and neutrophils, recognize and engulf large particles, such as bacteria, cellular debris, or other foreign invaders.
Correct answer: Phagocytosis6793. Which organelle in eukaryotic cells functionally resembles mesosomes of prokaryotic cells?
- A. Golgi apparatus
- B. Cell membrane
- C. Endoplasmic reticulum
- D. Mitochondria
Explanation: Mitochondria functionally resemble mesosomes as they are involved in respiration like mesosomes.
Correct answer: Mitochondria6794. Which type of molecule will make channels for the movement of neutral substances down the concentration gradient?
- A. Phospholipids
- B. Nucleic acid
- C. Protein
- D. Carbohydrates
Explanation: Carrier-proteins are integral protein particles having a certain affinity for specific solutes. As a result, they facilitate the transport of molecules across the membrane.
Correct answer: Protein6795. Under which of the following conditions,you can find predominance of free ribosomes?
- A. A cell that is secreting proteins
- B. A cell that digests food particles
- C. A cell producing cytoplasmic enzymes
- D. A cell that enlarges its vacuole
Explanation: Free ribosomes are mainly responsible for synthesizing proteins of different organelles like the nucleus, mitochondria, peroxisome, and other important cytosolic proteins. So the correct answer is c a cell that is producing cytoplasmic enzymes.
Correct answer: A cell producing cytoplasmic enzymes6796. Mitochondria have enzymes for all of these processes except:
- A. Replication of DNA
- B. Fatty acid metabolism
- C. Krebs cycle
- D. Fermentation
Explanation: Fermentation is a metabolic process that does not occur in the mitochondria. Instead, it takes place in the cytoplasm of cells. Fermentation is an anaerobic process that occurs when oxygen is not available or limited. It involves the partial breakdown of glucose or other organic molecules to produce energy in the form of ATP (adenosine triphosphate) without the involvement of the mitochondria. Common examples of fermentation include lactic acid fermentation and alcoholic fermentation.
Correct answer: Fermentation6797. Which of the following feature is common between prokaryotes and eukaryotes?
- A. A membrane-bounded nucleus
- B. A cell wall made up of cellulose
- C. Presence of ribosomes
- D. Linear genome
Explanation: Ribosomes are membraneless so they are present in both prokaryotes and eukaryotes.
Correct answer: Presence of ribosomes6798. Water-soluble pigments found in plant cell vacuoles are
- A. Xanthophylls
- B. Carotenoids
- C. Chlorophylls
- D. Anthocyanin
Explanation: Anthocyanins are the water soluble pigments present in the plant cell vacuoles. These vacuoles appear in different colours like red, blue or purple. Anthocyanins are extracted from edible plants for various purposes.
Correct answer: Anthocyanin6799. Different cells have different sizes. Arrange the following cells in ascending order of their size. Choose the correct option among the followings: (i) Mycoplasma(ii) Ostrich eggs(iii) Human RBCs(iv) E. coli
- A. (i), (iv), (iii) and (ii)
- B. (ii), (i), (iii) and (iv)
- C. (i), (ii), (iii) and (iv)
- D. (iii), (ii), (i) and (iv)
Explanation: The smallest cell is mycoplasma (0.1-0.5 µm). The bacterial cell measures 3-5 µm in length. Erythrocytes are 6-8 µm in diameter. So, the correct option is (i)-(iv)-(iii)-(ii).
Correct answer: (i), (iv), (iii) and (ii)6800. Which of the following is derived from the cell membrane?
- A. Plasmid
- B. Mesosome
- C. Nucleosome
- D. All A, B, C
Explanation: Mesosome is a convoluted membranous structure formed in a prokaryotic cell by the invagination of the plasma membrane.
Correct answer: Mesosome