Question

_{Be prepared for a short answer/essay type question similar to the following: Angiosperms (flowering plants) have wide distribution in the biosphere and the largest number of species in the plant kingdom. d. Discuss the function of FOUR structures for reproduction in angiosperms and the adaptive (evolutionary) significance of each. e. Mosses (bryophytes) have not achieved the widespread terrestrial success of angiosperms. Discuss how the anatomy and reproductive strategies of mosses limit their distribution.}

Answer 1

Angino sperms that contains both male and female gametophytes with in the same flower are called complete and are considered to be androgynous or hermaphroditic.The flower has main four parts that is calyx(sepals),corolla(petals),androecium(male reproductive structure),and gynoecium(female reproductuve structure)

sepals:The outer most whorl of the flower has green,leafy structures known as sepals.Which are collectively called calyx and its help to protect the unopened bud.The calyx is commonly pesistent and the evident when the fruit matures in contrast to more- short lived petals and stamens

corolla:The second whorl is comprised of flowers,usually brightly colored collectively called the corolla.It attracts insects and birds for pollination.and petals also produce sugar containing compounds ,and also produce fragrance for attracting pollinators.petals often developed into a nectar-containing extension of a tubular corolla called a spur..

The androecium has stamens with anthers that contain the microsporangia,The innermost structure in the flower is gynoecium it consist of stigma style and ovary. Androecium produce pollen,there are generally contain two spore sacs durimg maturation the partion between the adjacent microsporangia of a pair breaks down.So that they only containing two pollen sacs at that time stamen release the pollen

BRYOPHYTES:These plants are classified accoding to their sexual system monoicous and dioicous.Sexual system in bryophytes are apparently related to breeding system with out crossing occuring in dioicous species and self fertilization in monoicous once.dioicous species are associated with low frequncy of fertilization and rarity of sporophytes.