Question

Bordered pits are very common among tracheids of
A) Monocotyledons
B) Dicotyledons
C) Pteridophytes
D) Gymnosperm

Answer 1

Bordered pits are referred as cavities that are important components in the water-transport mechanism of higher plants in the lignified cell walls in xylem conduits.

Complete answer:
First we should know about bordered pits to answer this question. Lignin deposition includes the entire primary cell wall of Tracheid during cell wall thickening, with the exception of openings called bordered pit-pairs.

Now, let us find the solution from the options-
-> As the name suggests, the monocots or monocotyledons in their seeds possess a single cotyledon, or embryonic bud. Thus, option A is not the correct option.
-> Dicotyledon is any representative of the flowering plants, or of the angiosperms, possessing in the seed embryo a set of leaves, or cotyledons. Thus option B is not the correct option.
-> Pteridophytes seem to be the first vascular plants with less advanced bordering pits as compared to gymnosperms, they have less developed. Thus, option C is not the correct option.
-> A pit pair shares a similar primary wall and middle lamella membrane and acts as a border with the elevated wall across the pit aperture. The appearance of bordered pits is known to be a primitive character that has developed as seen in flowering plants into lateral, alternate pits. Gymnosperm is basic to angiosperms, but they have more plentiful boundary pits.

Thus, the correct answer is option (D) Gymnosperms.

Note: The composition of pits differs dramatically among organisms, with the porosity and hardness of pit membranes exhibiting significant variations. Since higher porosity decreases hydraulic strength but raises embolism susceptibility, variations in pit structure are anticipated to correspond with trade-offs among water transport capacity and protection.