Question

An aphid pierces its proboscis into _______to get plant juices
A. Xylem
B. Phloem
C. Cambium
D. Vascular bundle

Answer 1

Hint: An aphid pierces that plant which has easily available plant juices, plus Aphids generally suck sap from the stem part. Xylem and phloem are the conducting tissue i.e. these cells are involved in the transport of water and food in the plant.

Complete answer: An aphid pierces its proboscis into phloem to get plant juices. Xylem and phloem are conducting tissue, which transports water and food across the plant part respectively. Plant juices are plant food produce at the leaf which is transported to different plant parts by phloem. Similarly Xylem transport water from root to different plant parts.
-Cambium: It is a layer of undifferentiated cells present between the xylem and phloem. During secondary growth, it produces secondary xylem inside and secondary phloem outside. The activity of the cambium is responsible for the annual ring in the tree.
-Vascular bundle: The vascular bundle consists of xylem and phloem. In the dicot plant cambium is present between xylem and phloem and hence the vascular bundle is called open. Whereas in monocot, cambium is absent hence the vascular bundle called closed.
Hence, the correct answer is Option B
Additional information:
Both xylem and phloem are complex tissue i.e., they are formed of more than one type of cell. Some cells are dead i.e., without protoplast and some are living.
-Xylem: It is consists of four types of cells in Angiosperms i.e. Tracheids, Vessels, Xylem parenchyma, and Xylem fibers.
-Phloem: It also consists of four types of cells in Angiosperms i.e. Sieve tube elements, Companion cells, Phloem parenchyma, and Phloem fibers.

Note: Xylem, phloem, and cambium constituent of the vascular bundle. The plant juices are present in the vascular bundle but specific to its phloem, constituent of the vascular bundle which contains the plant juices.