Which of the following is not a component of phloem?

Articulated laticifers or latex vessels are prominent in

$A$ vascular bundle having phloem at the centre encircled by xylem is known as:

What are the specialized epidermal cells surrounding the guard cells called?

$A$ student observed grass and $Hibiscus$ plants in his garden during noon. To his surprise,only the leaves of grass were found rolled inwards. The reason could be

Which one of the following is not part of the Epidermal tissue system?