Which of the following cells regulates the cellular function of sieve tube cells?
Companion cells
Sieve tube cells (sieve tube elements) are the food-conducting cells of phloem. At maturity they lose their nucleus and most organelles, so they cannot control their own cellular activities.
Each sieve tube element has a closely associated companion cell, which has a nucleus and dense cytoplasm and is connected to it by plasmodesmata. The companion cell carries out the metabolic work and regulates the functions of the sieve tube cell, including the loading and unloading of food.
Xylem vessels are dead cells that conduct water and minerals. Phloem fibres are thick-walled sclerenchyma cells that give mechanical support, and phloem parenchyma stores food and other substances; none of these controls the sieve tube cells.
Hence, Companion cells.
Which feature helps pteridophytes survive better than bryophytes in places with limited moisture?
Which tissue can be found in a fern stem cross-section, but is missing in Bryophyta and Thallophyta?
The seeds of gymnosperms are considered 'naked' as:
______ vascular tissue in plants contains specialised cells called sieve tube elements, and ______ is their primary function.
Which of the following is NOT a part of Xylem tissue?
Which of the following characteristics helps gymnosperms survive in cold and dry regions?
Which condition is most favorable for the growth of fungi?
A plant grows mainly in water and has a body that is not differentiated into true roots, stems, and leaves. To which group does it belong?
Which meristem is located at the base of certain plants and helps them regenerate after cutting?
Which of the following plant groups includes a green mat-like plant growing on a damp wall that lacks true roots and vascular tissues?
Which of the following is a type of nutrition?
I. Heterotrophic
II. Autotrophic
Part of N 2cycle that is opposed to N 2fixation is:
Which among the following is the reproductive part of a plant?
Fibres (Adventitious) roots are found in :
In which Part of the flower does Meiosis take place ?