seed germination

Seed

Juvenile embryo in suspended state with necessary nutrients to begin growth

Do seeds need nutrients to start growing?

No

Germination

Series of biochemical events leading to the seed becoming an active plant

How many phases in germination?

3

Phase 1

1.) water enters the seed

2.) seed water content increases rapidly

3.) existing RNA translated to new protein

4.) mitochondria in cells are repaired

Phase 2

1.) water uptake slows and stops

2.) DNA is transcribed to make new RNA which then translates to make new protein

3.) hormones are made

4.) new mitochondria are made

5.) endosperm is weakened and food is released to support embryo

6.) embryo starts growing

7.) testa (skin) of seed degrades and is about to rupture

Phase 3

1.) testa ruptures

2.) radicle (seed root) emerges

3.) endosperm provides nutrients while radicle takes hold and begins to take in water and nutrients

4.) seedling grows

5.) water uptake increases rapidly

6.) growth accelerates

Seed dormancy

State in which seeds are stopped from germinating even under favorable conditions

Favorable conditions

Temperature, water, light, gas, seed coats, and other mechanical restrictions

Testa

Skin / Seedcoat

Plumule

Shoot

cotyledon

seed leaf

Radicle

embryonic root

Where are seeds from

Fruit

Where are fruits from

Flowers

Fruit is ____ on a flower

Ovary

Seeds are ____ on a flower

Ovule

Embryo

2n

Endosperm

3n minus 1 sperm nuclei + 2 egg nuclei

Imbibition

Water enters the seed