Reproduction in Plants

Sexual Reproduction in Angiosperms Reproduction takes place in the flower. During reproduction, there is a mixing of male & female genetic material (in angiosperms & gymnosperms). The mixing results in offspring having slightly different genetic material makeup from each other & from their parent plants (in angiosperms & gymnosperms).

Flowers A flower has 4 main parts: 1. sepals 2. petals 3. stamens-male part of the flower 4. carpels-female part of the flower

Parts of a Flower

Sepals Located on the outside of the plant Green & leaf-like Protects the flower

Petals Lie inside the sepals Protect the male & female parts of the plant (stamens & carpels)

Stamens Male part of the flower that forms a ring around the female parts. Produce pollen (dust like powder)

Carpels Female part of the flower Each carpel has an ovary & a stigma Inside the ovary are ovules that contain the female egg cells

Pollination & Fertilization 1. Pollen is transferred from the stamen (male part) to the carpel (female part) by wind, gravity, water currents or animals. 2. After pollination, the male part travels down to the ovule & fertilizes the egg. 3. a zygote is formed (first stage of seed development) 4. The zygote develops into an embryo (the baby plant).

5. After the embryo stage, the ovary dies & a fruit is formed with the seed inside. 2 parts of a seed: 1. seed coat-protects the seed 2. cotyledon-place where food for the seed is stored

6. Seeds are dispersed by animals, wind, water, people or explosions (not fiery ones). 7. Once it is dispersed, it is time for the seed to germinate (grow) into a whole new plant/tree.

Life Cycle of an Angiosperm

Reproduction in Gymnosperms Reproduction takes place in the cones. 1. female cone produces an ovule where the egg is made 2. male cone produces pollen 3. pollen falls or is carried into the female cone 4. pollen travels down to the egg (pollination) & the sperm is released

5. egg is fertilized & becomes a zygote 6. as the zygote develops, it turns into an embryo (seed) that is protected by a seed coat 7. seed falls to the ground & grows into a new tree (or it is dispersed)

Life Cycle of a Gymnosperm