Question

Interfascicular cambium is situated
A) In between the vascular bundles
B) Inside the vascular bundles
C) Outside the vascular bundles
D) In pith

Answer 1

Hint:Cambium is a thin strip of primary meristem present between the xylem and phloem in dicot stems. Cambium is absent in the monocotyledons. The cambium is responsible for the secondary growth in the plants. It is a meristematic tissue present between the permanent tissues (xylem and phloem).

Complete answer:
The meristematic tissue is the tissue in the active region of cell growth. The lateral meristem is made up of three types of cambium:
Fascicular vascular cambium : It is the meristematic tissue which develops within the vascular bundles. It is also called interfascicular vascular cambium.
Interfascicular cambium : The meristematic tissue which develops between the vascular bundles is called interfascicular cambium.
Cork cambium : This lateral meristem forms the cork, a tough protective material during the secondary growth.
Hence, lateral meristems are secondary meristems on the basis of origin (except interfascicular cambium) and lateral on the basis of location.

Now let us gather information about given options :
A) In between the vascular bundles : interfascicular cambium is secondary in origin that is not present during early stages of growth so it is formed later and is present in between the vascular bundles that is xylem and phloem
B) Inside the vascular bundles : it is a kind of primary meristem that appears early in the plant. So it is present inside vascular bundles that are xylem and phloem as it is present from the starting.
C) Outside the vascular bundles : during secondary growth a lateral meristem forms the cork that is present outside the vascular bundles that is xylem and phloem. It is tough protective material during the secondary growth.
D) In pith: it is made up of soft and spongy cells. It is made up of vascular cambium. It is present in the centre. It is made up of parenchymatous cells with a smaller number of intercellular spaces. And is absent in the root of dicots.

Hence the correct answer is option ‘B’ that is Inside the vascular bundles.

Note:When there is no cambium present between the xylem and phloem elements. The bundle is said to be closed. Such vascular bundles because of the absence of cambium do not possess the ability to form secondary xylem and phloem tissues. Hence, they are called closed vascular bundles as they are 'closed' for the secondary growth. e.g., Monocot.