The common medullary rays between dicot stem and root is

(1)primary medullary rays

(2)secondary medullary rays

(3)Both A and B

(4)None of the above

Secondary growth occurs in

(1)dicot root and stem of angiosperms

(2)dicot root and stem of gymnosperms

(3)monocot roots

(4)Both 1 and 2

Lenticels are present in

(1)stem only

(2)root only

(3)Both A and B

(4)root, stem and leaf

The more correct function of the medullary rays in dicot roots are

(1) water conduction only

(2)food conduction only

(3)food and water conduction

(4) food and water conduction in radial direction

Which of the following is known as living mechanical tissue

(1)parenchyma

(2)collenchyma

(3)sclerenchyma

(4)All of the above

Which one is true of collenchyma?

(1)forms the hypodermis of dicot stem

(2) present below epidermis in layers or patches

(3)thickened corners due to cellulose, hemicellulose, and pectin deposition

(4)All of the above

The main mechanical tissue of the plant is

(1)sclerenchyma

(2)collenchyma

(3)parenchyma

(4)Both B and C

Sclerenchyma is

(1) dead and lignified

(2)consists of long, narrow, thick walled cells

(3)may be in the form of fibres and sclereids

(4)All of these

Which one is true for sclereids

(1)highly thickened dead walls with narrow lumen

(2)present in fruit walls of nuts

(3)pulp of guava, pear, and sapots

(4)All of the above

Sclerenchymatous fibres are

1. thick walled, elongated and pointed cells

2. contains simple and bordered pits

3. smallest  cells in plant body

4. All of these