1. Seeds contain an embryo which includes the plumule, radicle, hypocotyl, and one or two cotyledons that provide nutrients. 2. A seed also has a protective seed coat and may contain endosperm that stores additional food. 3. Germination occurs when a seed absorbs water, softens its coat, and the root and shoot emerge from the soil using energy from the cotyledons or endosperm. Factors like moisture, oxygen, temperature, and soil quality affect germination.

1. Lesson 3.4 Seeds
Seeds are where the baby plant
or embryo is found

2. Parts of a seed:
1.Embryo – plant itself

3. Parts of the Embryo:
a. Plumule (epicotyl) part of
shoot that gives rise to the
first true leaves
b. Radicle = root system
c. Hypocotyl = becomes the
stem of the new plant

4. Parts of the Embryo:
a. Plumule (epicotyl) part of shoot that gives rise to the first true
leaves
b. Radicle = root system
c.Hypocotyl = becomes the stem of the new plant
d. Cotyledon(s) = seed leaves
of the embryo; provides
nutrients for embryo

7. A seed can have:
•one cotyledon called monocots
ex. corn
or
•two cotyledons called dicots
ex. lima beans

8. Parts of a seed:
1. Embryo – plant itself
2. Seed coat – protective covering
 some seeds have a double coat
 some seeds have a hilum or scar
where they attached to the ovary

9. Parts of a seed:
1.Embryo
2. Seed coat
3. Endosperm = additional stored
food found in monocots that
surrounds the embryo.

10. •Germination - sprouting of the
seed
•Dormancy - period of inactivity
to help seed not sprout during
bad conditions

11. •Viability
ability of seeds to germinate or (how
long a seed can wait and still sprouts)
some seeds are viable only a few days
others for thousands of years – there is
great variation in viability
Indian lotus viable
thousands of years

12. Steps to germination:
1. plant absorbs water
2. seed coat softens
3. root and shoot push through soil
4. energy used from cotyledons and
endosperm through process of cellular
respiration (starch – sugar-energy)
5. Growth of stem, leaves and root.
Cotyledons often grow with stem
protecting leaves and providing energy.

13. Factors affecting
germination:
1. Moisture – biggie, seed goes
from 10% water to 200%
water
2. Oxygen for cellular
respiration
3. Temperature – best 68-86F
4. Soil – varies in quality

15. George Washington
Carver
Called “the Plant Do ctor”
Taught agriculture at
Tuskegee Institute
Studies chemurgi or ways
to use plants to make
products