AP BIOLOGY

Detailed explanation-1: -Conifers, which are monoecious plants, produce both male and female cones. Known as pollen cones, the male cones produce microspores, which result in pollen grains, also known as male gametes. The sperm cells will eventually enter the egg cells through a pollen tube.

Detailed explanation-2: -All conifers produce male and female cones. Sometimes on the same tree, sometimes not. The pinecones we see are only the female cones. The male cones are much smaller and not showy.

Detailed explanation-3: -In gymnosperms, a leafy green sporophyte generates cones containing male and female gametophytes; female cones are bigger than male cones and are located higher up in the tree. A male cone contains microsporophylls where male gametophytes ( pollen ) are produced and are later carried by wind to female gametophytes.

Detailed explanation-4: -The female cone (megastrobilus, seed cone, or ovulate cone) contains ovules which, when fertilized by pollen, become seeds. The female cone structure varies more markedly between the different conifer families, and is often crucial for the identification of many species of conifers.

Detailed explanation-5: -In pines, pollen is produced in staminate (male) cones, which is wind-blown to young female cones. After fertilization, scales develop on the cone. Generally, two seeds develop on the upper surfaces of each scale of the female cone.