Symbiosis and Anemones

1
  In the illustation below, you can see the anemone Adamsia sp. attached to the shell inhabited by the hermit crab Pagurus bernhardus. This is a mutualistic symbiotic relationship, as both parties benefit. The anemone gains the ability to move around, and find different prey options, instead of being stuck in one place, and the hermit crab gets protection from predators.

2

  A Lybia tesselata, or boxer crab, is shown in the illustration below holding the anemone Triactis producta in its claws. It appears to be a mutualistic relationship, as the anemone is only found with the boxer crab, but how the anemone benefits is unknown. Perhaps, as in the case above, it benefits from being carried to new sources of food by the crab.  On the other hand, the benefit to the crab is obvious, since its claws are far too small to be used for defense. So it instead keeps two smaller anemones, trimming them down to the right size, as "boxing gloves" for protection.

3
  The anemone below is  Anthopleura elegantissima, or aggregate anemone. At first glance it does not look like a symbiotic relationship is taking place, after all it is just a green sea anemone. However, the green coloration is caused by dinoflagellates and other phytoplankton, which release oxygen for the anemone. In return, the anemone grows in the photic zone so the algae have enough sunlight, and provides carbon dioxide, both of which are necessary for photosynthesis.

4
  A Stenorhynchus seticornis, or arrow crab, is commonly found living on Lebrunia neglecta (which also has a mutualistic relationship with algae), and this would seem to indicate some type of mutual relationship. This is not the case however. The arrow crab lives in the anemone's tentacles for protection, but does nothing for the anemone in return. This is called a commensalistic relationship, a type of symbiosis in which one member benefits, but neither aids or harms the other.

Marine Zoology Homework2: Contrast Porifera and Cnidarians

Differences Between Porifera and Cnidaria:

1. Porifera do not have specialized tissues.  Cnidaria do.

2. Porifera are sessile as adults.  Cnidaria vary.  Some are sessile as adults (e.g. anemones, corals), but some are planktonic as adults (e.g. jellyfish).

3. Porifera have hard skeletal elements called spicules.  Although corals build a hard exoskeleton, cnidaria do not have spicules.

4.  Cnidaria have powerful stinging cells called nematocysts.  Porifera do not.

5.  Cnidaria have tentacles.  Porifera do not.

6.  Porifera are asymmetrical.   Cnidaria have radial symmetry.

7.  Porifera have pores called ostia through which they take in water (and plankton), and an opening called an osculum through which filtered water is expelled.  Cnidaria do not have these structures.  They have a single opening that acts as both mouth and anus.

8.  Almost all sponges are filter feeders.  All cnidaria are predators.

9.  Porifera do not have any sort of a nervous system.  Cnidaria have a primitive response system.

10.  Their larvae are different.  Porifera have lavrae with long flagella.  Cnidarians have larvae with shorter cillia.

Marine Zoology: Invertebrates I Homework: Build a model of a sponge

For my Marine Zoology class homework, I had to build a model of a sponge.

I chose to build a 3D digital model using Tinkercad.  I had to label the various parts of the model.

Here are some screen shots of the model, and one that I altered to add labels,

Here is a video of me explaining the model.

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Plankton Race: Marine Bio 101 Homework, Week 4, Part 2

For Marine Biology, I had to design a plankton which had adaptations for buoyancy and drag that we discussed in class and get it to take as long as possible to sink to the bottom of a tank of water.

The water had to be 12 inches deep.

The plankton could not be bigger than 3 inches long on its longest side.  Mine was about 2.5 inches long on its longest body side. 

The body was a sponge, which was a flat body plan.  The sponge had air pockets, an adaptation for buoyancy which some real plankton have.  It also had spikes made of bamboo skewers (another adaptation which increases buoyancy).

To test the design, you hold it in the water so it is just sumberged, then let go.  (You don't just drop it into the water.) 

It floated.

So I attached some flagella-like structures made of fishing line and beads.  I also added some screws to the sponge with a rubber band to give it some mass. 

It went straight to the bottom in less than 2 seconds. 

Next, I removed some beads and made the flagella shorter.  I figured that would cut down the drag a bit.

That helped it to sink somewhat slower. It took approximately 3 seconds.

It still needed something. 

Next, I attached a cloth parachute to it (a drag increasing adaptation, similar to the body plan of jellyfish). 

That slowed it down, but not enough.

I added streamers (less than 3 inches long) (also to increase drag.)  And then a second set of streamers.

Now it just sank.  Fast.

I cut the streamers shorter.  That helped a little bit, but not enough.

So next I added some vaseline to the bottom of the sponge to mimic lipid or fat pockets that some real plankton have.  This increased the buoyancy enough that my plankton slowly sank to the bottom of the tank. 

At this point, my parents helped me by timing it and shooting video.  Unfortunately, my mom's camera did something really weird, and it lost the audio of me explaining the project, so I am typing this up instead. 

It wouldn't download either, showing up as only a still photo, but it ran on mom's camera.  She used another camera to video the video so I could upload it.  Sorry if the video quality is not the best, but you can pretty much make out my dad's phone that he used as a timer. 

I did several tests of the final plankton.  The best time I had was 10.2 seconds, and the next best was 9.7 seconds. 

Marine Biology Homework: Plankton Project

My homework this week was to do a project on plankton.  I had to select 5 phytoplankton and 5 zooplankton and give the domain and kingdom each is classified under, and for the zooplankton, note whether the organism is holoplankton (remains plankton for its entire life) or meroplankton (is plankton for only part (the larval stage) of its life cycle.)

Here are the phytoplankton:

First, we have an organism called Stephanopyxis palmeriana, a Chain Forming Centric Diatom.  It is in the Domain Eukaryota, and Kingdom Chromista.

Next, we have Ceratium fusus, Ceratium tripos and Ceratium macroceros, which are Dinoflagellates, in Domain Eukaryota and Kingdom Protista:

These are Scyphosphaera apsteinii, which are Coccolithophores.  They are in Domain Eukaryota and Kingdom Protista:

This is Eucampia zodiacus.  It is a Chain Forming Centric Diatom (which forms spirals) and is in Domain Eukarota, Kingdom Protista:

This is a Centric Diatom, Rhizosolenia robusta.  It is in Domain Eukaryota, Kingdom Protista:

This is Pleurosigma sp., a Pennate Diatom, from Domain Eukaryota, Kingdom Protista.

The following organisms are zooplankton.

First, we have a Paddleworm, Tomopteris helgoandica, which is holoplankton from Domain Eukaryota, Kingdom Animalia:

Next we have Ophiothrix fragilis, the Common Brittlestar, which is meroplankton.  It is in Domain Eukaryota, Kingdom Animalia.

This is the Porcelain Crab, Pisida longicornis.  It is in Domain Eukayota, Kingdom Animalia.

This is the Sea Angel, Clione limacina.  It is holoplankton in Domain Eukaryota, Kingdom Animalia.

This is Acartia Clausi, a type of Copepod.  It is holoplankton in Domain Eukaryota, Kingdom Animalia.