Which of the following is made up of dead cells?

1. Collenchyma

2. Phellem

3. Phloem

4. Xylem parenchyma

Cortex is the region found between

(1) Epidermis and stele

(2) Pericycle and endodermis

(3) Endodermis and pith

(4) Endodermis and vascular bundle

The balloon-shaped structures called tyloses

(1) Original in the lumen of vessels

(2) characterise the sapwood

(3) are exetentions of xylem parenchyma cells into vessels

(4) are linked to the ascent of sap through xylem vessels

Specialised epidermal cells surrounding the guard cells are called ?

1. subsidiary cells

2. bulliform cells

3. lenticels

4. complementary cells