Sieve Tube Elements
Trending Questions
- Companion cells
- Sieve tube elements
- Tracheids
- Transfusion tissue
Sieve tube cell is
Uninucleate
Multinucleate
Enucleate
Dead
Reason: Mature sieve tubes have parietal cytoplasm and perforated sieve plates.
- If both assertion and reason are true and the reason is a correct explanation of the assertion
- If both assertion and reason are true but the reason is not a correct explanation of the assertion
- If the assertion is true but the reason is false
- If both the assertion and reason are false
- Albuminous cells and sieve cells
- Companion cells only
- Both sieve tubes and companion cells
- Sieve tubes only
Seive tubes are characterized by
Absence of septa
Peripheral cytoplasm
Perforated longitudinal walls
Simple oblique septa
While xylem is always open and used for transport of water, phloem is open only when the food needs to be transported. Which of the following reasons supports this statement?
Sieve tubes have companion cells that control their activity. Xylem vessels have no such cells.
The sieve tube opening can be closed by callus, that can be dissolved when not needed.
Sieve tubes have valves that can open and close when needed
Sieve tubes have a large vacuole, no nucleus and a peripheral cytoplasm
Callose plugs are formed during winter in _________.
The end walls of tracheids
The walls of vessels
Sieve tube elements
The walls of sclereids
- enucleated
- nucleated
- multinuclated
- dead cells