Practice question · Select all that apply
Which statements about phloem are correct?
Hints
- Three describe phloem correctly; one confuses it with xylem.
- Sugars move to wherever they are needed, which can be up or down.
Show the answer
- A. Sieve-tube elements lose their nucleus at maturity
- B. It transports sugars from source to sink
- C. Companion cells maintain the sieve-tube elements
Why
Phloem moves sugars from source to sink, in whichever direction that requires, down to roots, up to fruits, or both at once in different tubes. Only xylem is strictly unidirectional.
Practise Plant Ground and Vascular Tissues
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