May 11, 2006 – Chlorophyll Extraction, My 7th graders did this! Options

[Samantha_Dassler_Barlow]

Date: May 11, 2006

GPS Coordinates
Latitude: 62°24.8’ N
Longitude: 174° 33.9’ W



Map - May 11, 2006

Today has been a slow day. Between trying to take a whole group photo of all the people on the Healy and the helicopter operations, we have been on this station all day long. Usually it takes about 4 hours at a station and today, we have been at this one for at least 8 hours.

We had a little bit of excitement today, though. We had our own little SAR case. SAR stands for search and rescue. (Maybe you can recall the reason why the ship was delayed to Dutch Harbor.) A few of the crewmembers took the Zodiac out for a small cruise. The Zodiac is a small raft, inflated-type boat with an outboard motor on the back. See picture. Well, the motor quit. So, the ship had to turn around and go out to where they were stuck. They were trying to paddle their way over. Eventually, they made it back to the ship safely. Just a few hours earlier, some of the scientists took the zodiac out to get ice samples. I feel like the scientists were lucky because that could have happened while they were out there.


Mini SAR

Patty and I really got our feet wet and our hands dirty today. We spent some time working with the sediment.

This next part of my journal is for my 7th graders! Do you remember extracting leaf pigment (chlorophyll) from leaves? Of course you do! Well I did that very same extraction process at one of the stations today.

The vanVeen grabbed a bunch of mud and critters from the seafloor. We collected a fresh sample of mud and brought it into the lab. I know you are wondering how chlorophyll and mud are related at this point so I’ll tell you. Phytoplankton float around near the surface of the water and photosynthesize (use light to make their own energy). Phyto means plant and plankton means floating, so floating plants. These are the plant-like base of the food chain around here, or primary producers of the ocean. I think they are classified as algae – autotrophic protists. My 6th graders should appreciate that. Eventually, these little plant-like organisms fall to the seafloor and even though it is dark down there, they can live for quite a while. Lee is looking to see how much of them are down there because the bottom dwellers eat them. If there is a lot of chlorophyll in the sediment, then there are probably more bottom dwelling animals growing there, which would also mean that there are marine mammals that eat the bottom dwellers nearby. So that would be a very productive system. It amazes me to think that these little creatures that filter-feed, like clams, can live on the seafloor in the darkness and mud, yet they still get their veggies!

So, after we get these 2 little vials of mud – which has the phytoplankton/chlorophyll in it, we take it into the lab. First you have to break up the cell walls to let the chlorophyll out. My 7th graders should remember mashing their leaves in alcohol using a glass stirring rod. Well, I used acetone as my solvent and put it in the vials with the mud, then shook it up a little bit. Then, we let it incubate in the refrigerator for a little bit to make sure that all the chlorophyll would come out of the cells.


Acetone

As the chlorophyll dissolved in the acetone, it produced this yellowish, brownish, greenish liquid. This would be just like the liquid with the leaf chlorophyll in it that my 7th graders filtered.


Pouring Chlorophyll

Then, we poured the liquid into a small test tube and stuck it in a fluorometer. It measured the concentration of chlorophyll.


Fluorometer

Last, I wrote down the number on the data table next to the spot for that sample number.


Recording Data

Besides making the connection with something that my 7th graders have done in class, I also identified with different parts of this whole process.
• They collect the samples the exact same way every time to limit variables.
• Every sample is meticulously labeled with a sample number and the station number so they know where they got it.
• They collect lots and lots of samples so that they have replication of data.
• The data is recorded on a well-labeled data table.

Sound familiar?

[Ute_Kaden]

Hi Sam,
Greetings from Hanna HS, Brownsville, TX. We are following your trip with great excitement. I have recognized people from last year’s crew in your photos. Say Hi to them from me.
Good luck and have fun!

Ute Kaden ( HOTRAX 05)