Transformation of meristematic cells into specific permanent tissues occurs by the process of
- A.Cell differentiation.
- B.Cell division.
- C.Cell multiplication.
- D.Cell regeneration.
Correct answer
Explanation
The correct answer is A, Cell differentiation. Cells made by the meristem lose the ability to divide and take on a fixed shape, size and job, and this change is called differentiation.
Meristematic tissue is found at the tips of roots and shoots (apical meristem), at the base of leaves and internodes (intercalary meristem) and along the sides of stems and roots (lateral meristem, the cambium). Its cells are small, with dense cytoplasm and large nuclei, and they keep dividing. As the new cells move away from the growing region, they stop dividing and become permanent tissues such as parenchyma, collenchyma, sclerenchyma, xylem and phloem.
B, cell division, only increases the number of cells; it does not give them a special form or function.
C, cell multiplication, is another way of saying the cells grow in number, not that they change into permanent tissue.
D, cell regeneration, is the regrowth of lost or damaged parts, not the normal maturing of meristem cells.
Exam tip: meristem divides; permanent tissue forms by differentiation; apical meristem adds length, lateral meristem adds girth.
Practice Questions
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- A.Absorption
- B.Partition
- C.Solubility
- D.Volatility
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Read the full explanation →Which one of the following phenomena CANNOT be exhibited by sound waves ?
- A.Reflection
- B.Refraction
- C.Interference
- D.Polarisation
Show answer
Sound in air is a longitudinal wave, and only transverse waves can be polarised. Polarisation means restricting the vibrations of a wave to a single plane.
Read the full explanation →Which one of the following is NOT a luminous object ?
- A.Sun
- B.Electric lamp
- C.Candle
- D.Moon
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Read the full explanation →In experiment #1, a bar magnet is moved towards a conducting wire loop axially, with the magnet's north pole facing the loop. In experiment #2, the same process as in experiment #1 is repeated except that the south pole of the magnet faces the loop. Which one of the following statements is true in this context?
- A.The direction of current in the loop will be of opposite nature in both the experiments.
- B.The direction of current in the loop will be the same in both the experiments.
- C.No current will flow in either of the two experiments.
- D.More current will flow in the loop in experiment #1.
Show answer
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Read the full explanation →Which one of the following statements about classification of plants is correct?
- A.Thallophytes have well differentiated body design
- B.Funaria is a fungus
- C.All Pteridophytes are Phanerogams
- D.Vascular system is not found among Bryophytes
Show answer
Mosses and liverworts have no xylem or phloem, so water moves through them cell to cell. Bryophytes, such as Funaria (a moss) and Marchantia (a liverwort), are called the amphibians of the plant kingdom because they live on land but need water for fertilisation.
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