AIM: SWBAT describe the process of pollination and its significance to plant reproduction

Please Do Now: 1) What is the male part of the flower called?

2) What is the female part called?3) Where are energy and resources stored

within the seed?

Agenda

• Do Now• Pollination• Experimental Design• Video Clip

What is pollination?

• The process of moving pollen from the stamen of a flower to the pistil of the same or different flower

• This can happen in 3 main ways:– Wind pollination– Water pollination– Biotic pollination

Why is pollination necessary?

• Pollination is necessary for fertilization to occur, and for seeds to develop

• Pollen fertilizing flowers from the same plant defeats the purpose of sexual reproduction

What is pollen like?• However it moves,

pollen usually has to make a long journey

• It is adapted to make successful fertilization as likely as possible– Super tiny– Often spiked for sticking– Millions of pollen grains

produced per flower

How are plants adapted to their type of pollination?

Water Pollination• Rare: Less than 1% of

plants are pollinated by water

• Mostly plants that live partially or entirely in water

How are plants adapted to their type of pollination?

Wind Pollination• About 20% of plants are

wind pollinated• Their pollen are

extremely small and light• Cause allergies• Small, random chance

that any single pollen grain will find a stigma of the same species

How are plants adapted to their type of pollination?

Biotic Pollenation• Accounts for 80% of all plants• Pollinators (animals that do the

pollinating) visit the flower to get nectar (sugar water) from the flower

• Usually pollen grains end up stuck to the body of the pollinator and are transported from flower to flower while they are getting more nectar

What are the pollinators?

• Insects most common– Bees– Wasps– Flies– Butterflies

• Also birds (hummingbirds)

• Bats • Ground mammals for

plants with heavy pollen

How did these interactions evolve?

• Many pollinator/flowering plant combinations have evolved together, so they are the only species each other depend upon– Ex: Heliconia

Importance

• Most major crops are insect pollinated

• That means, no pollinators, no food

Colony Collapse Disorder

• Decimating colonies of bees that do much of the pollination for our agricultural crops

• Mostly the result of overuse of pesticides

Experimental design Mondays• Every Monday, we will take 15-20 minutes to practice

our experimental design skills• I will pose a scenario to you, and then you will

attempt to design an experiment that addresses that question

• This will be turned in so I can read your work• The experiment you design should include a

hypothesis with a dependent variable and an independent variable, some things that must be kept constant between your groups, and a brief 3 sentence description of your experiment.

Independent and dependent variables

• Independent: what you as the scientist are manipulating to see its effect

• Dependent: what you are measuring to see the response of the manipulation of the independent variable

Scenario #1

You are investigating the effect of soil Nitrogen levels on seed germination? You have access to a variety of different seeds, and Nitrogen fertilizer.

REMEMBER: Include a hypothesis with a dependent variable and an independent variable, some things that must be kept constant between your groups, and a brief 3 sentence description of your experiment.

Scenario #2You are trying to figure out if plants produce more

flowers when it is warmer out. You have access to different greenhouses in which you can control the temperature. Design an experiment to test this question.

REMEMBER: Include a hypothesis with a dependent variable and an independent variable, some things that must be kept constant between your groups, and a brief 3 sentence description of your experiment.