Tag: root

The adventitious roots found in the epiphytes are known as the epiphytic root. These roots hang freely in the air and absorb the moisture from the air by a special type of tissue called as velamen. Epiphytic plants are sometimes called as air plants because they do not have roots in the soil. For example, Vanda.

In plants like Arceuthobium, Rajflesia, Sapria, Podostemon, shoot develops for flowering otherwise roots form main part of the plant.

Passage cells are endodermal cells of older monocot roots, which have retained thin walls and casparian strips. They are not suberized and waterproof. They allow symplastic flow of solutes, such as calcium and magnesium into the stele.

Calyptrogen is a histogen which produces the root cap.
Thus, the correct answer is option A.

The thick waxy layer covers the surface of aerial organs is termed as Cuticle. It is composed of a waxy substance called cutin. It is thin in mesophytes and extremely thick in xerophytes. The cuticle is absent in hydrophytes and underground organs and young roots. Other three options the bearing Cuticle.

So, the correct option is 'Young roots'.

The correct option is B.

A quiescent centre is a small group of cells with low mitotic activity (no cell division). Quiescent centre is to be found at the tips of growing roots, in the root meristem and are surrounded by groups of dividing cells.
So, the correct answer is 'Root tip'.

The external protective layer in dicot root is called as epiblema or piliferous layer. The cells of epidermis extend into unicellular root hairs. In the root cap there is no root hair present. In absence of root hairs water absorption is not possible. So, the correct answer is option B.