Chlorophyll & Photosynthesis Surviving in hot environments and - - PowerPoint PPT Presentation

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Jul 13, 2023 265 likes •368 views

Plant adaptations, Chlorophyll & Photosynthesis Surviving in hot environments and making the most of light What we are going to do today Visit the Faculty Experimental grounds look at plant adaptations to their environments and

SLIDE 1

Plant adaptations, Chlorophyll & Photosynthesis

Surviving in hot environments and making the most of light

SLIDE 2

What we are going to do today…

Visit the Faculty Experimental grounds– look at plant adaptations to their environments and collect your experimental plants and leaves Experiments: 1) Heat tolerance in different leaves – which plants are best suited to surviving hot environments? 2) Chlorophyll– making the most of light a) How do plants manage in the shade? Or…… b) How do variegated leaves manage to survive?

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Different plants have different ability to tolerate high

temps.

Heat stress affects photosynthesis
Measure the heat tolerance using a “Plant stress meter”

(FluoroPen)

1) Heat tolerance in different leaves: which plants are best suited to surviving hot environments?

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2) Making the most of light: How do plants manage in shade?

www.saps.org.uk http://www.controlledenvironments.org

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Chlorophyll absorbs the red and blue light - appears green. Two main types

chlorophyll a and chlorophyll b.

Carotenoids absorb the blue-green and blue light - appears yellow or

yellow-orange.

Anthocyanins absorb blue, blue-green and green light- appear red or

purple to our eyes.

http://www.sidthomas.net/SenEssence/Evolution/pigments.htm

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Antennae Reaction Centres

SUN SHADE

Photon of light Excitation energy

1. Shade plants can invest in more light capturing structures

(antennae) than in light ‘using’ structures (reaction centres).

2. Also increase the number of photosystems, so higher total chl

content

3. Often have larger, thinner leaves and longer petioles.

More chl b than chl a in shade ..lower a/b ratio

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2) Making the most of light: How do variegated plants manage to survive?

Some leaves are purple, red or variegated.

But do the non-green parts have chlorophyll

as well?

Extract anthocyanin using baby oil?

"Coleus-1" by Aftabbanoori - Own work. Licensed under CC BY-SA 3.0 via Wikimedia Commons -

SLIDE 8

Measure the chlorophyll content using scanning spectrophotometer

Chlorophyll content and a/b ratio

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What now?

Quick visit to our experimental grounds to select our leaves and pick our samples and variegated plants. Equipment: take zip lock bags and damp tissue paper