Toothpick Fish Lab Analysis

In this lab, we simulated a gene pool of toothpick "fish" in a stream ecosystem. This enabled us to experiment with the different genes, and the environment, but also gave us a chance to further enhance our knowledge of heredity and expression. We were given a cup of colored toothpicks, representing genes. Before I go on, here is a key to all the alleles that I will talk about.

          G = green

          r   = red (is recessive to green, but incompletely dominant to yellow.)

          y  = yellow (is recessive to green, but incompletely dominant to red.)

Genotypes that are responsible for each fish color:

      

       Green: GG, Gr, Gy

       Red: rr

       Yellow: yy

       Orange: ry

There were four generations that we had to create/simulate. 

First Generation (12 Fish)

#   | Genotype | Phenotype|

1   | Gy            | Green         |

2   | Gy            | Green         |

3   | Gy            | Green         |

4   | Gy            | Green         |

5   | Gr             | Green         |

6   | Gr             | Green         |

7   | Gr             | Green         |

8   | Gr             | Green         |

9   | yy             | Yellow        |

10 | rr               | Red            |

11 | ry              | Orange       |

12 | ry              | Orange       |

Of these twelve fish in the first generation, 75% of them were green, but none of them were homozygous. Approximately 33% were orange, around 8% were red, and about 8% were yellow. However, all of the yellow fish died, because they were not able to camouflage. Therefore, we were only left with eleven fish that could survive and reproduce, creating following generations. 

Second Generation (11 fish)

#   | Genotype | Phenotype |

1   | Gy            | Green          |

2   | Gy            | Green          |

3   | Gy            | Green          |

4   | Gy            | Green          |

5   | Gr             | Green          |

6   | Gr             | Green          |

7   | Gr             | Green          |

8   | Gr             | Green          |

9   | rr               | Red            |

10 | ry              | Orange        |

11 | ry              | Orange        |

Although the second generation is exactly like the first, minus the one yellow fish, bear in mind that it is, in fact, different. About 72% of the fish were green, none of them homozygous. Approximately 9% were  red, and around 18% were orange. 0% of the fish were yellow, as all the yellow alleles were shadowed by a green allele or incompletely dominant with a red allele. 

Third Generation:

#   | Genotype | Phenotype |

1   | Gy            | Green          |

2   | Gy            | Green          |

3   | Gy            | Green          |

4   | Gr             | Green          |

5   | Gr             | Green          |

6   | Gr             | Green          |

7   | GG           | Green           |

8   | rr               | Red             |

9   | ry              | Orange        |

10 | ry              | Orange        |

11 | ry              | Orange        |

In the third generation, approximately 63% of the fish were green, 9% of them being homozygous. About 27% were orange, and around 9% were red. Notice that all the yellow alleles have not completely disappeared.

Fourth Generation:

#   | Genotype | Phenotype |

1   | Gy            | Green          |

2   | Gy            | Green          |

3   | Gr             | Green          |

4   | Gr             | Green          |

5   | Gr             | Green          |

6   | GG           | Green          |

7   | yy             | Yellow         |

8   | rr              | Red             |

9   | ry              | Orange        |

10 | ry              | Orange        |

11 | ry              | Orange        |

In the fourth generation, about 54% of the fish were green. Around 27% were orange, and about 9% were red, and 9% were yellow.

However, the yellow fish didn't die out this time. Factory waste was dumped into the stream, killing all the algae. Therefore, all the green fish were wiped out, but the rocks and sand that were left exposed were good camouflage for the red, yellow, and orange fish. Because of this environmental disaster, all the green alleles disappeared. Since they were dominant, they always showed up, so heterozygous fish with green genes were killed. But the reason that the yellow alleles still appeared were because they were recessive, sometimes shadowed by a green allele, or incompletely dominant with a red allele. To reiterate, the alleles for green scales disappeared the fastest.

In this experiment, there were a few variables. One of them was the environment, and another were predators. With the change of one of these, the whole fish population could be impacted. For example, if the environment was hostile towards the red fish, and predators ate them because they couldn't camouflage, the population would not be drastically affected. Sure, it would lose a few members, but orange fish and heterozygous fish carrying the gene for red scales could pass the alleles on. Like we have demonstrated, one simple factor can change the whole population. And when the fish population is affected, the species around it are impacted. For instance, the plankton and organisms that the fish eat would thrive. In contrast, the population of predators, such as bears or other carnivorous animals, would decline. Then the species linked to those would be impacted, and so on and so forth.

To summarize, this lab helped me learn about heredity, alleles, and environmental impact.

The Simple Science of Genetics--Punnett Squares

By dictionary.com's definition, genetics is "the science of heredity dealing with resemblances and differences of related organisms resulting from the interaction of their genes and the environment." But let me simplify that for you. Genetics is a part of biology. It delves into the genes and characteristics that show up in organisms, based on the combinations of alleles (that's basically DNA) that they inherit from their parents. There. That's pretty simple, right? 
Before we go on, however, here's a brief background on genetics: Gregor Mendel, an Augustinian monk, is considered to be the father of genetics. He was in charge of tending to the garden at the monastery in which he resided, and took a great interest in the different traits that were seen in the same species of plants. So Mendel conducted experiments with pea plants. It was simple, but turns out, the effect on modern society would be monumental. By cross-breeding pea plants, Mendel was able to successfully conclude many things about genetics. His discoveries set the foundation for this scientific study.
Now that we are aware of the history of this spectacular thing- GENETICS!- we can move on to Punnett  squares. A Punnett squares is basically a table that displays the probabilities of offspring having different combinations of traits from their parents. 
A few key terms to know are:
alleles: forms of a gene
genotype: the actual alleles that show up in the offspring's DNA (e.g. Rr, heterozygous, homozygous dominant, rr) 
*the "gen" part of genotype can remind you of the word "gene," which helps you remember that genotype has to do with the actual allele combinations.*
phenotype: the actual traits that can be seen. (e.g. Black hair, blue eyes, etc.)
*the "ph" part of phenotype can remind you of the word "physical," which lets you know that its the actual characteristics that can be seen.*
dominant allele: an allele that, if present in the offspring, always shows up, as it blocks out, or dominates, the recessive alleles.
            Dominant alleles are represented with a capital letter (e.g. R)
recessive allele: an allele that doesn't show up in the offspring if it's paired with a dominant allele. 

            Recessive alleles are represented with a lower-case letter. (e.g. r)

homozygous: having two of the same alleles 
            homozygous dominant- having two dominant alleles (e.g. RR)
            homozygous recessive- having two recessive alleles (e.g. rr)
heterozygous: having two different alleles, one dominant, and one recessive.
            (e.g. Rr)
A Punnett square is sort of like a multiplication table. There are rows, and there are columns, and the number (or in this case, letter) in one column multiplies to the number (or letter) in the row, creating a box that is common between both of them. 
Here is an example of a monohybrid Punnett square. It is the simplest form of the table, and very easy to do. Remember, the capital letter is the dominant allele, and the lower-case one is the recessive allele.

In this Punnett square, two heterozygous parents (they each have two different alleles, one dominant, and one recessive) are crossed. 


A= black hair
a= blond hair


This is the key to our Punnett square. It is very important to have a key to make sure that you know what each letter stands for. 


Now let's get to reading the Punnett square. It's not very difficult. 
Genotypes:
AA= homozygous dominant
aa= homozygous recessive
Aa= heterozygous (if you want to say dominant after "heterozygous," feel free to, if it helps you remember that the dominant allele always blocks out the recessive.)
Phenotypes:
AA= black hair
aa= blond hair
Aa= black hair (remember that the recessive allele cannot be seen if the dominant allele is present.)


This is how you would read the Punnett square:
If asked for the genotypes- 25% homozygous dominant, 25% homozygous recessive, 50% heterozygous
If asked for the phenotypes- 25% blond hair, 75% black hair.
*A monohybrid Punnett square only has four parts, therefore one box would be 25%, two boxes would be 50%, and three boxes would be 75%*


So we've done it! We have covered the definition and history of genetics, and monohybrid Punnett squares! It's quite simple, and I hope that this post has helped many of you grasp the concept of genetics better.

Metal Tracking Bands--Harmful to Penguins

Recently, studies have shown that the metal tracking bands that scientists use to monitor penguins are, in fact, harmful to the birds. Over a time period of ten years, the banded animals have produced 39% less chicks and come to meet with a survival rate that is 16% less than their non-tracked counterparts. Researchers chipped 100 King Penguins, half of them with bands, half of them without bands, and tracked them to further prove their studies. Apparently, banding increases the mortality rate in birds that are not very fit. Also, the banded penguins arrived at breeding areas around two weeks late, so they did not have enough time, or enough energy, to reproduce and take care of their young. Rory Wilson, an ecologist who didn't have anything to do with the research, said that the metal bands provided extra drag and resistance, which hindered the penguins' athletic abilities. These devices would also injure the flippers. Ultimately, predators would be able to get at the penguins with more ease. However, bands are inexpensive, durable, and convienent, and scientists still may continue to use them.

To read more, visit

Tracking Bands Harm Penguins- LiveScience.com

NJ PINE BARRENS WEBSITE

Please visit this website on the NJ Pine Barrens

njpinebarrens.weebly.com

Harry Potter to.....Ecology?

Science concepts can be applied to almost every book I have read in my life so far. But....what about ecology? Although Harry Potter and the Deathly Hallows, by J.K. Rowling, is not a book about ecology itself, ecology concepts, such as symbiosis, and death rates, and more.

Parasitism can be applied to this novel. Parasitism involves one organism living in or on another organism and harming it. You see, Lord Voldemort has split his soul into seven; six times intentionally, and the seventh by accident. When Voldemort tried to kill Harry when Harry was one, Voldemort was blasted apart, not literally speaking, of course. Part of his soul attached itself to Harry, and has been living off of him for a while. Here is a quote directly from the book:

     "  'We have protected him because it has been essential to teach him, to raise him, to let him try his strength,' said Dumbledore, his eyes still tight shut. 'Meanwhile the connection betwen them grows ever stronger, a parasitic growth....' "

The book directly states that Voldemort's soul is a parasite in Harry's body. Voldemort's soul is one organism, and Harry, the other.

The second concept that can be applied to this book is death rates. A death rate is the number of deaths in a population at a certain time. There are two death rates in this book that are stated, as well as implied: the death rate of wizards, and the death rate of Muggles, or non-magical people. Ever since Lord Voldemort came back alive, the death rate has increased. More people die, mostly wizards, trying to fight Voldemort, or face his wrath, and Muggles, who Voldemort kills just for the fun of it. The number of deaths in the wizarding and Muggles populations at this time under Voldemort's power is ginormous, while in the previous, as well as coming years, it was not as large.

All in all, science concepts, even ecology concepts, can be applied to any book, if you just know where to look.

Mutualism

Trees that are found in my community.

The picture to the right is an example of mutualism in my community. Mutualism is the relationship between two species, in which both species benefit. While the ivy gets a place to grow, it also prevents the tree from getting eaten by other organisms. The ivy only embeds itself into the first layer of the bark, not causing any damage to the tree.

Limiting Factors In My Community

The picture to the right is an example of two limiting factors in my community. Grass is biotic, or alive, while rocks are abiotic, or non-living. They are both limiting factors. Both rocks and grass are shelter, and grass also makes a good food source. If there is not enough grass, then organisms may starve. If there is not enough rocks, then small organisms, like insects, may die out. These factors limit the environment and organisms around them.