May you please help me with a short answers please. Also I dont need explanation
ID: 199259 • Letter: M
Question
May you please help me with a short answers please. Also I dont need explanation for the answer. Thank you. Pine Trees The pine tree is the dominant sporophyte generation (Fig. 15.4) in the life cycle of a pine. Vascular tissue extends from the roots, through the stem, to the leaves. Pine tree leaves are needlelike, leathery, and covered with a waxy, resinous cuticle. The stomata, openings in the leaves for gas exchange, are sunken. The structure of the leaf and the leaf's internal anatomy are adaptive to a drier climate. In pine trees, the pollen sacs and ovules are located in cones. Pollen sacs on pollen cone scales contain cells which undergo meiosis to produce microspores. Microspores (n) become sperm-bearing male gameto- phytes (pollen grains). Seed cone scales bear ovules where cells undergo meiosis to produce megaspores. A megaspore (n) becomes an egg-bearing female gametophyte Pollination occurs when pollen grains are windblown to the seed cones. After fertilization, the egg becomes a sporophyte (2n) embryo enclosed within the ovule, which develops a seed coat. The seeds are winged and are dispersed by the wind. 1. Which part of the pine life cycle is the sporophyte? 2. Which part of the pine life cycle is the male gametophyte? The female gametophyte? 3. Where does fertilization occur and what structure becomes a seed?Explanation / Answer
Pine trees are conifers and carry both male and female sporophylls on the same mature sporophyte. Therefore, they are monoecious plants.
1. The part of the pine life cycle is an adult sporophyte- Diploid
The dominant mature sporophyte generation is - pine tree
2. Haploid
3.Pine tree is a conifer. The Pollen grains are produced by the male cone. A grain of pine pollen contains all the genetic information from the pine tree on which it hangs. The grain of pollen finds its way to a receptive female cone, which acts as the female reproductive organ in pine plant. Once the pollen lands on the cone, it grows a long thin tube into the center of the cone where the egg is located. There, the genetic information in the pollen grain is combined with the genetic information in the egg, and a fertilized embryo results.The embryo in the pine plant grows into a seed and the cone becomes brown and develops scales.