Group Four Seeded, vascular plants (ex: angiosperm)

carpel style stigma ovary stamen filamentanther petal sepal Sepals and petals are modified leaves. Sepals are outermost layer that protects developing flower Petals can help to attract animal pollinators A stamen is the male structure of the flower Anther produces pollen grains Filament supports the anther The innermost layer of a flower is the female carpel. Stigma is sticky tip Style is tube leading from stigma to ovary Ovary produces female gametophyte

Flowering plants can be pollinated by wind or animals Wind pollinated flowers have small flowers and large amounts of pollen. Animal pollinated flowers have larger flowers and less pollen. Many flowering plants are pollinated by animal pollinators. – Pollination occurs as animal feeds from flower to flower – Animal pollination more efficient than wind pollination

Fertilization Takes Place Within The Flower Male gametophytes (pollen grains) are produced in the anthers. –Male spores produced in anthers by meiosis –Each spore divides by mitosis to form two haploid cells –Two cells form a single pollen grain Pollen grain Anther Stamen Filament Cell that will divide & become the pollen tube Cell that will divide & become 2 sperm

Many cells can be made in the ovule One cell becomes the egg One cell becomes 2 polar nuclei The rest die One Female Gametophyte Can Form In Each Ovule of A Flower’s ovary Ovule (Egg) 2 Polar Nuclei (Each = 1n) [

1. Pollen sticks to animal or is released into wind. Angiosperm Life Cycle

1. Pollen sticks to animal or is released into wind.

2. Animal finds new flower to feed on & pollen grains land on the stigma (pollination) 3. Pollen tube grows towards the egg and 2 nuclei transfer down into the ovule egg.. Let’s zoom in

4. Angiosperms go through the process of double fertilization. 1 sperm fuse with the egg = zygote 1 sperm fuse with the polar nuclei = triploid (3n) endosperm Endosperm(3n)Endosperm(3n) Z y g o t e Double Fertilization

Endosperm Seed Coat Embryo Endosperm provides food supply for embryo 5. Each ovule becomes a seed. 6. The surrounding ovary grows into a fruit.

7. Flower dries up and fruit falls to ground.

8. Animals eat fruit….seeds come out the other end…

9. Seeds get dispersed. 10. Seed germinates (sporophyte), and the cycle starts over. Ground

Plant typeSporophyteGametophyteDominant Phase? MossStalk with cup at tip, which is where spores are produced. More familiar, carpet-like plant that produces specialized gametes XX - Archegonium XY - Antheridium GAMETOPHYTE FernMore familiar, leafy plant with clusters of spore producing sacs (sori) Haploid plant body is size of a finger nail, produces both male and female parts SPOROPHYTE Conifer (Gymnosperm) More familiar - like pine trees, produces male and female cones that produce spores Male gametophytes are pollen grains  sperm Female gametophytes are microscopic  eggs SPOROPHYTE Flowers (Angiosperm) More familiar - apple tree, peach tree, zucchini, berries, etc. Contain flowers that produce male and female spores Pollen grains are male gametophytes  2 haploid cells = pollen tube + sperm Female gametophyte in ovule  egg + 2 polar nuclei SPOROPHYTE