Explanation

Pteridophytes are the first terrestrial plants to possess vascular tissue.

A pteridophyte is a vascular plant (with xylem and phloem) that reproduces by means of spores.

Because pteridophytes produce neither flowers nor seeds,

They are sometimes referred to as "cryptogams", meaning that their means of reproduction is hidden.

Explanation

Wind-pollinated flowers have a large, feathery stigma in order to trap the airborne pollen grains.

Examples of plants that participate in wind pollination are wheat, rice, corn, and barley.

Explanation

Plants in the Solanaceae family have an obligately superior ovary.

In the Solanaceae family, the ovary is oblique in position due to the tilting of posterior carpels to the right and anterior carpels to the left at an angle of 45 degrees.

The ovary is superior, bilocular with many ovules on swollen axile placentation.

Explanation

Tyloses are outgrowths from xylem parenchyma cells

They grow into the lumen of tracheary cells through pits, balloon out, and occlude the cell interior.

Tyloses are typically associated with the process of defense against pathogens

They are commonly found in the xylem of certain trees and plants.

Explanation

Natural resistance refers to an organism's inherent ability to resist diseases or pests due to genetic factors.

Explanation

The "eyes" on potato tubers are nodes where buds can develop into new shoots.

Explanation

Soil pollution can be caused by various factors including acid rain, ozone, and aerosols.

Explanation

The prothallus of Nephrolepis (a type of fern) is haploid.

The prothallus is haploid, since it grew from a spore which had been formed by meiosis.

It does not have any vascular tissue and uses small rhizoids to anchor it to the ground.

On the underside of the prothallus the sex organs form.

Explanation

Excessive irrigation can lead to the accumulation of salts in the soil, causing salinity.

Salinity causes salt stress in plants.

Prolonged liberal irrigation results in nutrient depletion in the soil so that the plants do not grow properly.

Explanation

In gymnosperms, the ovule is covered by an integument, which is a protective layer.