Question
Question: In which portion of Cycas diploxylic vascular bundles are found? A. Root B. Stem C. Leaflet...
In which portion of Cycas diploxylic vascular bundles are found?
A. Root
B. Stem
C. Leaflet
D. Rachis and leaflet
Solution
Diploxylic means an arrangement of vascular bundle, where two types of xylem are present. These are the centripetal xylem and centrifugal xylem.
Complete answer:
In Cycas, rachis and leaflets have a diploxylic arrangement in vascular bundles.
Here, two types of xylem are found, usually at the stem cortex:
Centrifugal xylem that is present towards the centre.
It is seen in the leaf trace.
As the leaf-traces enter the leaf and rachis separate, centripetal xylem can be found.
It is present towards the outside.
So, the correct option is D. Rachis and leaflet.
Note: Vascular bundle is a transport system in the vascular plants that are made up of two forms of vascular tissue – xylem and phloem.
Xylem mainly transports water and few nutrients while phloem transports certain organic compounds.