Given below are sets of five terms each. Rewrite the terms in correct order in a logical sequence beginning with the first word that is underlined.
ROOT HAIR, Endodermis, Epidermis, Xylem, Cortex.
Topic: Path of water into the root
Answer
Root hair → Epidermis → Cortex → Endodermis → Xylem
This traces water from outside the root inward to the transport tissue: ROOT HAIR — an outgrowth of an epidermal cell, where water enters by osmosis EPIDERMIS — the outermost layer of the root CORTEX — the broad zone of cells beneath it ENDODERMIS — the single layer bounding the vascular cylinder XYLEM — the vessels that carry water up the stem
THE ORDER IS SIMPLY OUTSIDE TO INSIDE, and the ENDODERMIS is the one whose position students misplace. Its name says where it is — ENDO means inner, so it is the innermost layer of the cortex, immediately around the xylem.
Water passes from cell to cell by a chain of osmotic gradients, each cell inward being slightly more concentrated than the one outside it.