10/04/2310/04/23 K. Collins 2010 Middle School K. Collins 2010 Middle School MCHSMCHS

The Circle of LifeThe Circle of Life

(FOR PLANTS)(FOR PLANTS)

10/04/2310/04/23 K. Collins 2010 Middle School K. Collins 2010 Middle School MCHSMCHS

Parts of the SeedParts of the SeedThe embryo: is the little ‘baby plant’ when The embryo: is the little ‘baby plant’ when conditions are favourable it develops into a conditions are favourable it develops into a new plant. Inside the seed it is made up of new plant. Inside the seed it is made up of

3 different parts:3 different parts:1.1. PlumulePlumule- is like a leaf in its early - is like a leaf in its early

development, the baby shoot.development, the baby shoot.2.2. RadicleRadicle- It is the part that emerges first, it - It is the part that emerges first, it

is the baby root, it develops into the main is the baby root, it develops into the main rootroot

3.3. Cotyledons – primary leaves &/or food Cotyledons – primary leaves &/or food storagestorage

10/04/2310/04/23 K. Collins 2010 Middle School K. Collins 2010 Middle School MCHSMCHS

Seed StructureSeed Structure

10/04/2310/04/23 K. Collins 2010 Middle School K. Collins 2010 Middle School MCHSMCHS

GerminationGermination

When the conditions are When the conditions are right, the seed bursts open right, the seed bursts open and a new plant grows out. and a new plant grows out.

This process is called This process is called ‘GERMINATION’‘GERMINATION’

When germination is When germination is complete, the embryo has complete, the embryo has become a young plant or become a young plant or seedling.seedling.

10/04/2310/04/23 K. Collins 2010 Middle School K. Collins 2010 Middle School MCHSMCHS

What are the best What are the best conditions for Germination?conditions for Germination?

There are There are 33 environmental conditions environmental conditions that are needed by all seeds before they that are needed by all seeds before they germinate:germinate:

1.1. WaterWater

2.2. OxygenOxygen

3.3. Warm TempratureWarm Temprature

Activity:Activity: Propose reasons why each Propose reasons why each condition is required for germination of condition is required for germination of seed to take place?seed to take place?

10/04/2310/04/23 K. Collins 2010 Middle School K. Collins 2010 Middle School MCHSMCHS

Ideal conditions for Ideal conditions for germinationgermination

1. 1. Water:Water: Is necessary for the seed to swell & burst Is necessary for the seed to swell & burst open & then to transport food to the growing open & then to transport food to the growing embryoembryo

2. 2. Oxygen:Oxygen: helps provide the energy needed for helps provide the energy needed for growth & developmentgrowth & development

3. 3. Temperature:Temperature: needed varies with the particular needed varies with the particular type of plant E.g. Banksia requires high temp. to type of plant E.g. Banksia requires high temp. to burst the fruit so that the seeds may be released.burst the fruit so that the seeds may be released.

4. 4. LightLight not required for germination of most seeds, not required for germination of most seeds, once the young shoot breaks through it is once the young shoot breaks through it is needed so the plant can make it’s own food.needed so the plant can make it’s own food.

10/04/2310/04/23 K. Collins 2010 Middle School K. Collins 2010 Middle School MCHSMCHS

Seeds & GerminationSeeds & Germination