Plants having little or no secondary growth are
- Cycads
- Grasses
- Conifers
- Deciduous angiosperms
The Correct Option is B
Solution and Explanation
Top Questions on Secondary Growth
Identify the correct statements:
A. Lenticels are the lens-shaped openings permitting the exchange of gases.B. Bark formed early in the season is called hard bark.C. Bark is a technical term that refers to all tissues exterior to vascular cambium.D. Bark refers to periderm and secondary phloem.E. Phellogen is single-layered in thickness.Choose the correct answer from the options given below:
- NEET (UG) - 2023
- Biology
- Secondary Growth
- Match List - I with List - II.Choose the correct answer from the options given below.
List - 1 List - 1 a Lenticels i Phellogen b Cork cambium ii Suberin deposition c Secondary cortex iii Exchange of gases d Cork iv Phelioderm - NEET (UG) - 2021
- Biology
- Secondary Growth
- Secondary xylem and phloem in dicot stem are produced by
- NEET (UG) - 2018
- Biology
- Secondary Growth
- The vascular cambium normally gives rise to :
- NEET (UG) - 2017
- Biology
- Secondary Growth
- The secondary wall material Suberin is deposited on the walls of
- KCET - 2017
- Biology
- Secondary Growth
Questions Asked in NEET exam
A bob of heavy mass \(m\) is suspended by a light string of length \(l\). The bob is given a horizontal velocity \(v_0\) as shown in figure. If the string gets slack at some point P making an angle \( \theta \) from the horizontal, the ratio of the speed \(v\) of the bob at point P to its initial speed \(v_0\) is :
- NEET (UG) - 2025
- Pendulums
A full wave rectifier circuit with diodes (\(D_1\)) and (\(D_2\)) is shown in the figure. If input supply voltage \(V_{in} = 220 \sin(100 \pi t)\) volt, then at \(t = 15\) msec:
- NEET (UG) - 2025
- Semiconductor Diode
- The correct order of the wavelength of light absorbed by the following complexes is:
A. $[ \text{Co(NH}_3\text{)}_6]^{3+}$
B. $[ \text{Co(CN)}_6]^{3-}$
C. $[ \text{Cu(H}_2\text{O)}_4]^{2+}$
D. $[ \text{Ti(H}_2\text{O)}_6]^{3+}$
Choose the correct answer from the options given below:- NEET (UG) - 2025
- Coordination chemistry
- A uniform rod of mass 20 kg and length 5 m leans against a smooth vertical wall making an angle of \(60^\circ\) with it. The other end rests on a rough horizontal floor. The friction force that the floor exerts on the rod is (take \(g = 10\) m/s\(^2\)):
- NEET (UG) - 2025
- Common forces in mechanics
A constant voltage of 50 V is maintained between the points A and B of the circuit shown in the figure. The current through the branch CD of the circuit is :
- NEET (UG) - 2025
- Current electricity
Concepts Used:
Secondary Growth
Secondary growth is an increase in girth of thickness of the axis due to activity of lateral meristem. The tissues involved in secondary growth are two lateral meristems are vascular cambium and cork cambium.
Secondary Growth in Stem:
Formation of Cambium Ring-
- The cambium present between the xylem and phloem in vascular bundles is called Fascicular or Interfascicular cambium.
- In secondary growth, few medullary ray cells that are located between vascular bundles also become meristematic, and it is known as Interfascicular cambium.
Formation of the secondary tissues-
- The cambium ring cuts off cells on both sides. It produces secondary phloem outwardly and secondary xylem inwardly.
- The amount of secondary xylem cut off is more than the secondary phloem.
Secondary Growth in Root:
Vascular Cambium-
- The cambium is absent initially but develops later at the time of secondary growth.
- The pericycle cells lying outside the protoxylem and the conjunctive parenchyma cells on the lateral side of the phloem bundle become meristematic to form many cambial strips.
Cork Cambium-
- The cork cambium develops because of the tangential division of cells of the pericycle.
- The activity of cork cambium is like that found in the dicot stem, so it produces cork cells or phellem towards the outside and phelloderm or secondary cortex towards the inside.
Abnormal secondary growth:
- Due to absence of the cambium in monocots, monocots don’t show secondary growth and the vascular system is totally composed of primary tissues.
- The vascular bundles are irregularly scattered in the ground tissues, such that the cortex and other ground tissues can’t be differentiated.
- Dracaena, Yucca, Agave are examples of monocots that exhibit a peculiar type of secondary growth in thickness.