AP BIOLOGY

Detailed explanation-1: -The female sex organ is usually a flask-shaped structure called the archegonium. The archegonium contains a single egg enclosed in a swollen lower portion that is more than one cell thick. The neck of the archegonium is a single cell layer thick and sheathes a single thread of cells that forms the neck canal.

Detailed explanation-2: -Each archegonium holds one egg (in a swollen section called the venter) and the sperm enter through the channel in the narrower, tubular section (or neck). On the side of the venter opposite of the neck is the foot which anchors the archegonium to the gametophyte. Hence the correct option is C.

Detailed explanation-3: -Antheridium and archegonium are the male and female reproductive organs in bryophytes respectively.

Detailed explanation-4: -archegonium, the female reproductive organ in ferns and mosses. An archegonium also occurs in some gymnosperms, e.g., cycads and conifers. A flask-shaped structure, it consists of a neck, with one or more layers of cells, and a swollen base-the venter-which contains the egg.

Detailed explanation-5: -Bryophytes and gymnosperm have archegonia(plural form). Pteridophytes have also archegonium but are highly reduced.