The primary driving force for the movement of substances in the phloem is:
Transpiration pull
Capillary action
Root pressure
A pressure gradient created by active loading and unloading of sugars
Related Questions
Damaged sieve tubes are sealed by deposition of
Pectin
Callose
Suberin
Lignin
Which type of complex tissue are involved in formation of jute fibres
bast fibres
cortical fibres
xylem fibres
pith fibres
Which of the following is NOT a characteristic of phloem sieve tubes?
Presence of a nucleus at maturity
Living cells
Presence of sieve plates
Transport of organic substances
Which cells provide metabolic support to sieve tube elements?
Parenchyma cells
Companion cells
Sclerenchyma cells
Collenchyma cells
I. Vessel, II. Tracheids, III. Companion cells
Which of the following is/are living cells?
I and II
Only III
II and III
Only I
If sap collected from a plant stem shows a positive result for a test indicating high sugar concentration, it is most likely from which tissue?
Xylem
Phloem
Cortex
Epidermis
The conducting cells in the phloem of gymnosperms are:
Sieve tubes
Companion cells
Sieve cells
Tracheids
The specific arrangement of sieve elements and companion cells in phloem tissue, where a single companion cell is associated with multiple sieve elements, is MOST characteristic of which plant group?
Angiosperms
Gymnosperms
Bryophytes
Pteridophytes
A new organism is produced from a single parent without the involvement of gametes. This type of reproduction is known as:
Sexual reproduction
Asexual reproduction
Vegetative propagation
Parthenogenesis
Jute, flax, hemp fibres are morphologically?
Pericyclic fibres
Xylem fibres
Phloem fibres
Medullary fibres
