In grasses, intercalary meristem is usually located at
- A.root tip
- B.lateral sides of stem
- C.base of leaves
- D.shoot tip
Correct answer
Explanation
The correct answer is C, base of leaves. In grasses the intercalary meristem lies at the base of the leaf blades and internodes, between tissues that are already mature.
A meristem is a group of cells that keeps dividing. Apical meristems at the tips of the root and shoot make a plant longer, and lateral meristems on the sides make it thicker. The intercalary meristem is a third kind, found in grasses and other monocots. Because it sits low down at the base of the leaf, the growing part is left untouched when an animal grazes or a lawn is mown, and the leaf grows back from below. That is why grass recovers so quickly after cutting.
Option A is wrong because the root tip has the apical meristem of the root. Option B is wrong because the sides of the stem hold the lateral meristem, which adds girth. Option D is wrong because the shoot tip has the apical meristem of the shoot.
Exam tip: Apical at tips, lateral on sides, intercalary at the base of leaves and internodes in grasses.
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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