Which one of the following statements about meristematic tissues in plants is correct ?
- A.These are dead tissues and form wood
- B.They provide flexibility to plant due to their thickened walls
- C.These are present in the bark of a tree only
- D.Growth occurs in plants due to division of cells of these tissues
Correct answer
Explanation
The correct answer is D, growth occurs in plants due to division of cells of these tissues. Meristems are groups of actively dividing cells, and all new plant tissue comes from them.
Meristematic cells are living, small and closely packed, with thin cellulose walls, dense cytoplasm, a large nucleus and few or no vacuoles. Apical meristem at the tips of stems and roots makes the plant longer. Lateral meristem, the cambium, adds girth to stems and roots. Intercalary meristem, found at the base of leaves and at the nodes of grasses, lets those parts grow back after cutting. Cells formed by meristems later lose the power to divide and become permanent tissues.
A is wrong because meristematic cells are alive; wood is dead xylem tissue.
B is wrong because meristem cells have thin walls; flexibility comes from collenchyma.
C is wrong because meristems occur at stem and root tips and other places, not only in the bark.
Exam tip: apical meristem adds length, lateral (cambium) adds girth, intercalary regrows grass after grazing.
Practice Questions
View allWhich one of the following can charge an insulator?
- A.Current electricity
- B.Static electricity
- C.Magnetic field
- D.Gravitational field
Show answer
An insulator is charged by friction: rubbing transfers electrons from one surface to another, and because electrons cannot move through an insulator, the charge stays where it is as static electricity.
Read the full explanation →A glass prism splits white light into different colours. This phenomenon is called dispersion of light by prism. Which one of the following statements is correct?
- A.Red light will deviate the most and it is because of the reflection of light.
- B.Violet light will deviate the most and it is because of the refraction of light.
- C.Red light will deviate the most and it is because of the refraction of light.
- D.Violet light will deviate the most and it is because of the reflection of light.
Show answer
In glass, violet light has the shortest wavelength and the highest refractive index, so it bends the most; dispersion is a result of refraction.
Read the full explanation →A 5 N force is defined when a mass of 10 kg is accelerated with
- A.5.0 cm/s²
- B.0.5 m/s²
- C.0.5 cm/s²
- D.5.0 m/s²
Show answer
By Newton's second law, F = m × a, so a = F ÷ m = 5 N ÷ 10 kg = 0.5 m/s².
Read the full explanation →The breakdown of glucose in cytoplasm results in the formation of
- A.pyruvate and energy
- B.pyruvate and carbon dioxide
- C.pyruvate and oxygen
- D.pyruvate and nitrogen
Show answer
In the cytoplasm, glucose is split by glycolysis into two molecules of pyruvate, releasing a small amount of energy as ATP.
Read the full explanation →Which one of the following is the correct sequence in increasing complexity?
- A.Protein - Organism - Tissue - Organ
- B.Protein - Organ - Tissue - Organism
- C.Protein - Organism - Organ - Tissue
- D.Protein - Tissue - Organ - Organism
Show answer
Living things are built up level by level: molecules such as proteins form cells, cells form tissues, tissues form organs, organs form organ systems, and these together make an organism.
Read the full explanation →