Photosynthesis lab

Outline of the day

1. Turn in your lab reports at the front– More than 10 minutes late = bad

2. Any questions on last week’s lab?

3. Quiz

4. Introduction to the lab

5. Lab!

6. Check out• Get a stamp• Make sure I mark you down for attendance

Quiz

• Ends 10 minutes after it’s started

– Ends at: ____

Lab this week!

• Exploring photosynthesis!– What pigments are used– How light interacts with chlorophyll– Effect of photosynthesis on carbon-dioxide

concentration

Plants do photosynthesis in leaves and/or stems

CC licensed images from: http://flickr.com/photos/zachdurland/369427527/; http://flickr.com/photos/janinehealy/133056572/; http://flickr.com/photos/jayw/116902430/

Plants and algae have chloroplasts• Contain highly folded membranes

– Called thylakoids– Increases surface area exposed to light

• Chlorophyll is in these membranes– Chlorophyll “harvests” light

Chloroplast PD by It'sJustMe at http://en.wikipedia.org/wiki/Image:Chloroplast-new.jpgChloroplast in liverwort cells from Wellcome images http://images.wellcome.ac.uk/ B0005648 Credit M I Walker, Wellcome Images

Liverwort leaf cells A chloroplast

Summary of “typical” photosynthesis

Light

H2O

CO2Sugars

O2“Light reactions”

Chlorophyll-mediated

ATP NADPH

“Dark reactions”Calvin cycle

Artwork by Marc Perkins Note: In plants, all these reactions occur in the chloroplast

Lab hints:

• Put on lots of the photosynthetic concentrate for the pigment part

• Make sure your extract is crystal-clear after it’s been filtered

• Stop blowing into the phenol red as soon as it turns yellow– If you go too long, it will take hours to turn back!

Before you leave

• Clean up your work area– Wash glassware and store upside down

• Show me your lab report so I can stamp it– Need to have all data fields filled in– Complete at home and then turn in at the beginning of

next lab

• Remember that we’ll have a quiz at the beginning of the next class– 6-7 questions on today’s lab– 3-4 questions on the lab we’ll do next week

Notes for the instructor:

• Add any relevant cleanup instructions to the final slide (that slide is a generic one I’m adding to each presentation).

• I haven’t been able to find a good, single-image creative-commons licensed summary of photosynthesis that shows the inputs and outputs clearly (which I’ve indicated is missing on the photosynthesis summary slide in the presentation). I’ve sketched out the basics of what I’m looking for, but if you find a good one please let me know.

• I’d also love a better diagram/image of a single chloroplast.

License information

• This work is licensed under the Creative Commons Attribution-NonCommercial-ShareAlike 3.0 License. To view a copy of this license, visit http://creativecommons.org/licenses/by-nc-sa/3.0/us/ or send a letter to Creative Commons, 171 Second Street, Suite 300, San Francisco, California, 94105, USA.

• The slides in this presentation were originally created by Marc C. Perkins (http://faculty.orangecoastcollege.edu/mperkins).

• You are free to use, modify, and distribute these slides according to the terms of the Creative Commons license (e.g., you must attribute the slides, no commercial uses are allowed, and future distributions must be licensed under a similar license).

• Attribution should be given to Marc C. Perkins (and any later editors), including a link back to Marc’s current website. This applies both while distributing the slides and during use of the slides; attribution during use can be satisfied by, for instance, placing small text on at least one of the slides that has been shown (see below for an example).

Slides in this presentation based on those created by Marc C. Perkins. http://faculty.orangecoastcollege.edu/mperkins

History

• August 2007: Marc Perkins released first version. http://faculty.orangecoastcollege.edu/mperkins

(If you modify these slides and redistribute them, add your information to the list)

Extra slides

Summary of “typical” photosynthesis

Missing image:Summary diagram of

photosynthesis that showsthe inputs and outputs

clearly.

Summary of “typical” photosynthesis

Light

H2O

CO2Sugars

O2“Light reactions”

Chlorophyll-mediated

ATP NADPH

“Dark reactions”Calvin cycle