Transcript Figure 38.2 Review of an idealized flower
Figure 38.2 Review of an idealized flower Pistil Objective: You will be able to identify and give the function of the parts of a flower. Do Now: • Read pages 612 and 613 • For each part of the flower, write its function • This will take you a few minutes Male parts • Male part is called the stamen • The stamen consist of the anther and filament • Anther – Carries out meiosis to make pollen – Sperm cells are inside the pollen • Filament – Holds the anther into the air Female parts • Female part is called the pistil • The pistil is made of the stigma, style and ovary • Stigma is sticky to capture the pollen • Style is a passageway to the ovary • Ovary – Carries out meiosis to make eggs – The eggs are found within ovules Objective: You will be able to describe the events of pollination and fertilization. Do Now: • Read page 616 • What two things form from fertilization? Figure 38.5 Pollen grains have tough, ornate, and distinctive walls Pollination • Pollination is the transfer of the pollen from the anther to the stigma • If the pollen lands on a flower on the SAME plant it is called self-pollination – If it lands on a different individual then it is called cross-pollination • Pollinators are used to move the pollen Figure 38.3d1 Pollination modes Figure 38.1 Simplified overview of angiosperm life cycle Fertilization • Fertilization occurs within the ovule • There are actually two sperm cells • The first will fertilize the egg and form a zygote – This zygote will undergo cleavage to from an embryo Fertilization • The second sperm will fertilize a 2n cell and form a 3n cell called the endosperm – The endosperm is the food source for the embryo • This concept of two fertilizations is called double fertilization • It is unique to flowering plants. After Fertilization • The ovule itself will harden and become a seed • The ovary itself will change and become a fruit – The fruit is used for seed dispersal Figure 38.12 Development of a pea fruit (pod) Objective: You will be able to identify and describe the parts of a seed. Do Now: • Read page 618 • Give examples of fruits that everyone thinks are vegetables. Figure 38.11 Seed structure Seed Structure • The embryo consists of the hypocotyl and the epicotyl – Hypocotyl becomes the root – Epicotyl becomes the leaves and upper part of stem • Cotyledon is used as a food source • The seed coat protects the seed Seed germination • Once proper conditions are met, the seed will start to germinate. • Seed germination depends on water, oxygen and temperature • Why not light?