Which of the following statements is NOT correct ?
- A.Hardy-Weinberg Principle says that allele frequencies in a population is unstable
- B.Branching descent and natural selection are the two key concepts of Darwinian Theory of evolution
- C.Lamarckism is based on inheritance of acquired character
- D.The concept of mutation, gene flow, genetic drift, gene recombination and natural selection affect Hardy-Weinberg equilibrium
Correct answer
Explanation
The correct answer is A. The Hardy-Weinberg principle states the opposite: allele frequencies in a population stay stable, that is constant, from generation to generation.
The principle, worked out by G. H. Hardy and Wilhelm Weinberg in 1908, applies to a large, randomly mating population with no outside disturbance. It is written as p² + 2pq + q² = 1, where p and q are the frequencies of two alleles. When observed frequencies differ from these expected values, it shows that the population is evolving.
Option B is a correct statement, so it is not the answer: Darwin's theory rests on branching descent, all life sharing common ancestors, and natural selection. Option C is also correct: Jean-Baptiste Lamarck proposed that characters acquired through use and disuse, as in his example of the giraffe's long neck, are passed on to offspring. Option D is correct as well, because mutation, gene flow, genetic drift, recombination and natural selection are the five factors that disturb Hardy-Weinberg equilibrium.
Exam tip: Hardy-Weinberg = genetic equilibrium (p² + 2pq + q² = 1); five disturbing factors cause evolution.
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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Liver cells turn the toxic ammonia released from the breakdown of amino acids into urea through the ornithine cycle, also called the urea cycle.
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
Show answer
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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It binds oxygen at its iron-containing haem groups and carries some carbon dioxide on its protein chains. Each haemoglobin molecule has four polypeptide chains and four haem groups, and each haem iron can hold one oxygen molecule, forming oxyhaemoglobin in the lungs.
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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