seeds and seed germination topic: 2014 sources: css 101 dr. foster, plant soil science, and...

Seeds and Seed Germination

Topic: 2014

Sources: CSS 101 Dr. Foster,Plant soil Science, and technology by Biondo and Lee

To Make a Seed• Pollination

– Transfer of pollen form male to female parts

• Self pollination– Pollen pollinates a flower of the same plant

• Cross pollination– Pollen pollinates a flower from a different plant

• Double fertilization– Sperm fuses with an egg making a zygote. A second

sperm– nuclei fuses with two nuclei in the embryo sac. It

develops into the endosperm (later).

What makes a Seed• Seed

– Embryo, (young plant) and a food source

• Seed coat– Protective shell around embryo and endosperm

• Embryo– Little complete pant inside seed

• Cotyledons– Leaves on embryo

• Endosperm– Plants energy source

What makes a seed• Hypocotyl

– The part of the axis of a plant embryo or seedling plant that is below the cotyledons

• Plumule– The rudimentary terminal bud of a plant embryo

situated at the end of the hypocotyl, consisting of the epicotyl and often of immature leaves.

• Epicotyl– The stem of a seedling or embryo located between

the cotyledons and the first true leaves.

• Radicle– The part of a plant embryo that develops into a root.

More seed parts

• Micropyle– A minute opening in the ovule of a seed plant

through which the pollen tube usually enters.

• Hilum– The scar on a seed, such as a bean, indicating

the point of attachment to the funiculus (A stalk connecting an ovule or a seed with the placenta)

Conditions for Seed Germination

• Water

• Favorable temperatures (40 degrees Feinheight to 104)

• Oxygen

• Light or darkness

Germination Steps1. Water absorbed by seed through seed coat or

micropyle2. Seed cell enlarges3. Seed respiration increases4. Metabolic rate increases5. Protien synthesis increases6. Enzymatic activity begins7. Enzymes convert starch to sugar8. Embyro ruptures seed coat9. Root and shoot elongation