Which of the following is a characteristic of permanent tissue?
- A.Cells divide repeatedly
- B.Inorganic inclusions are absent
- C.Intercellular spaces are present
- D.Vacuoles are absent
Correct answer
Explanation
The correct answer is C, Intercellular spaces are present. Permanent tissues are made of cells that have stopped dividing and have taken on a fixed shape, size and function, and in simple permanent tissues such as parenchyma the loosely packed cells leave clear intercellular spaces through which gases can move. Permanent tissue is formed when cells produced by meristematic tissue undergo differentiation; the simple kinds are parenchyma, collenchyma and sclerenchyma, while xylem and phloem are the complex kinds. Such cells are usually large, with a big central vacuole and a thin lining of cytoplasm. A is wrong because repeated division is the mark of meristematic tissue, not of permanent tissue. B is wrong because permanent cells often hold inorganic inclusions such as crystals of calcium oxalate. D is wrong because large vacuoles are typical of permanent cells, while it is meristematic cells that lack them. Exam tip: meristematic - small cells, dense cytoplasm, no vacuole, no intercellular spaces; permanent tissue is the opposite on every count.
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
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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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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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