The “birds and bees” (and more!) of plant procreation!!!

Learning Goal 5:

Understand how POLLINATION and SEED

DISPERSAL are ADAPTATIONS that

allows for plant SURVIVAL, including:

• How it works/happens

• How other organisms may

SYMBIOTICALLY assist

What main survival need do POLLINATION

& SEED DISPERSAL meet?

How It Happens• Pollen falls from the anther (male – sperm) to

the stigma (female – leads to ovary/egg)

• Sperm cell (pollen) joins the egg cell in the ovary

• This fertilization process results in a seed (zygote)

• The fruit forms around the seed-hopefully making the seed more attractive for dispersal

What is pollination?

• Self-pollination: transfer of pollen from anther to stigma of same plant

• Cross-pollination - transfer of pollen to a different plant (of the same species)

Life Cycle of

an

Angiosperm (flower producer whose

seed is in enclosed in fruit)

Pollinating animals visit flowers not because they are pretty or smell nice, but because they offer sugary

nectar and protein rich pollen.

Flowers “trade” their food in hopes insects will be attracted and pollinate.

Bees

Both honeybees and native wild bees such as bumblebees are attracted to flowers with bright lively colors especially blues and yellows. Bees cannot see red. Notice the “landing pad”?

Bats

Bats typically pollinate at night in the areas such as American Southwest and the rainforest. Flowers pollinated by bats are typically large and sturdy. Night blooming flowers are the most common flowers pollinated by bats such as cactus flowers (saguaro)

ButterfliesBlossoms built for butterflies have lively colors, especially pinks, blues, and yellows. They are often grouped together in small masses.

The floral tube is usually narrow, restricted to allow for the butterfly’s slender tongue… fat bees keep away!

BIrds

Red is a banner that says “EAT HERE” to these fast flying birds (hummingbirds). These pink, orange, and red blossoms are narrowly constricted so that only narrow bills can enter. There is no landing platform on the flowers.

Gymnosperm- “Naked Seed”

Gymnosperm• Seed is not enclosed

(ex: pinecone)

• “Non-flowering” seed plant

• Tree or plant usually has needles that stay green year round (pine trees, firs, cedars and spruces)

How are pine needles a good adaptation for survival in cold climates?

Pollination of Gymnosperm

• Pollination occurs once a genetically compatible pollen grain lands directly on the “naked” ovule.

• It may be ONE YEAR or longer between pollination and fertilization!

• Once fertilized, the seed is released and grows into a new plant or tree

Compared…

• Gymnosperm and Angiosperm Seeds

•

Seed Dispersal

Seeds need to reach a destination where they can grow.

• How do they get there without a way to cause movement of their own?

• How do they not compete with the parent plant?

Birds• Birds can carry seeds to a

new location in their

mouths or the seeds may

be dispersed when the bird

poops!

Animals

• Many other animals

will do the same (eat,

drop, poop!)

Animals

• Some animals carry

the seeds on their

coat.

Wind

• The wind can carry

seeds a great

distance.

Water• Water can carry

seeds great

distances like

these coconuts

washing up on the

beach.

Gravity – Drop and Roll

Why might this be the LEAST beneficial?

Explosion