Which of the following statements is NOT true of Meiosis?
- A.As a consequence of Meiosis, the number of chromosomes is doubled in the resulting cells.
- B.Meiosis takes place in gonads for production of gametes.
- C.Meiosis takes place in two phases.
- D.During Meiosis, the genes of the parent cells are mixed in the resulting cells.
Correct answer
Explanation
The correct answer is A, that meiosis doubles the number of chromosomes, because meiosis does the opposite. It is a reduction division: one parent cell with the full, diploid set gives four cells with half the number of chromosomes, the haploid set. That halving is what keeps the chromosome number of a species steady, since a sperm and an egg each bring half and the fertilised egg is back to the full number. The other three statements are true. It takes place in the gonads, the testes and the ovaries, to make gametes. It runs in two rounds, meiosis I and meiosis II, with only one copying of the DNA. And during meiosis I the chromosomes of the two parents exchange segments by crossing over, so the genes are mixed and no two gametes are alike. B, C and D are therefore not the answer. Exam tip: mitosis keeps the number, meiosis halves it.
Practice Questions
View allThe fact that the planets move around the Sun, not in circles but in ellipses, was first demonstrated by
- A.Galileo
- B.Martin Luther
- C.Johannes Kepler
- D.Copernicus
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In 1609 Kepler showed that the planets move around the Sun in elliptical orbits, with the Sun at one focus of the ellipse.
Read the full explanation →Which one of the following statements is correct?
- A.Urea is produced in liver.
- B.Urea is produced in blood.
- C.Urea is produced from digestion of starch.
- D.Urea is produced in lung and kidney.
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Read the full explanation →Which one of the following is the correct sequence of passage of light in a compound microscope?
- A.Condenser-Objective lens-Eyepiece-Body tube
- B.Objective lens-Condenser-Body tube-Eyepiece
- C.Condenser-Objective lens-Body tube-Eyepiece
- D.Eyepiece-Objective lens-Body tube-Mirror
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Light passes through the condenser to the specimen, is picked up by the objective lens, travels up the body tube and reaches the eye through the eyepiece.
Read the full explanation →Which one of the following statements regarding haemoglobin is correct?
- A.Haemoglobin present in RBC can carry only oxygen but not carbon dioxide.
- B.Haemoglobin of RBC can carry both oxygen and carbon dioxide.
- C.Haemoglobin of RBC can carry only carbon dioxide.
- D.Haemoglobin is only used for blood clotting and not for carrying gases.
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Read the full explanation →Which one of the following statements regarding histone proteins is correct?
- A.Histones are proteins that are present in mitochondrial membrane.
- B.Histones are proteins that are present in nucleus in association with DNA.
- C.Histones are proteins associated with lipids in the cytosol.
- D.Histones are proteins associated with carbohydrates in the cytosol.
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They are the proteins around which DNA winds to form chromatin in the nucleus of eukaryotic cells. Histones are small basic proteins, rich in the positively charged amino acids lysine and arginine, which attract the negatively charged phosphate groups of DNA.
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