REPRODUCTION in Flowering Plants
I. FLOWERS Are the organs of reproduction in anthrophytes (flowering plants)
PARTS of the flower include: Sepals: enclose the flower bud and protect it until it opens Petals: attract pollinators
More flower parts- Pistil: female reproductive organ; ovules contain the female gametophyte generation, located inside the ovary at the base of the pistil Stamen: male reproductive organ, pollen grains contain male gametes and form inside the anther
II. POLLINATION A. Anther splits open when the pollen are mature B. Pollen are carried to the stigma by wind, water, or animals. THIS is pollination C. Plant reproduction is most successful when pollination rates are high Pollination is part of - D. Sexual reproduction, which results in greater genetic diversity (good for the species survival)
III. FERTILIZATION A. Pollen is carried to the stigma in pollination B. A pollen grain grows a tube down the style to the ovary C. Two sperm travel down the tube D. In a process called double fertilization, one of the sperm fertilizes the egg and the other unites with the central cell, forming an endosperm (which becomes food storage tissue)
FERTILIZATION IS THE UNITING OF THE SPERM AND EGG NUCLEI, CREATING A ZYGOTE.
IV. FRUITS AND SEEDS A. Following fertilization, the ovary develops into a fruit with seeds inside, while the rest of the flower dies B. Fruits help protect the seeds until they mature and help scatter seeds into new habitats -Fruits are the part of the plant that contains seeds: cucumbers, maple “helicopters”, green peppers, squash are all fruits.
FRUITS AND SEEDS, cont’d C. One or two cotyledons forms, which form leaves that will be used by the germinating seedling D. Food is derived from the endosperm E. Thus, the seed is an undeveloped plant embryo with stored food and protective coats
V. GERMINATION A. At maturity, seed coat dries and hardens, enabling it to survive harsh conditions B. Once conditions are favorable, seed germinates (develops into an embryo) and grows into a new plant.