Pollution in the Great Lakes

Plastics are a problem when they get into water. Most people know about issues such as the picture below.

http://saveourshores.org/what-we-do/pollution-prevention.php

There was a recent study that looked at smaller pieces of plastic and its effect on fish in the Great Lakes. Some of the plastic had come from...

"micro beads, or micro exfoliates, as abrasives in facial and body scrubs. They are too tiny forwater treatment plants to filter, so they wash down the drain and into the Great Lakes. The biggest worry: fish such as yellow perch or turtles and seagulls think of them as dinner."

Plastics are ubiquitous in our society. What are the solutions to this problem???

Biodiversity loss due to pesticides

I'm not sure why this is a surprise to anyone, but two new studies out of Europe have identified that areas that use more pesticides tend to have less biodiversity, especially with regards to invertebrates. There are two articles associated with this here and here.

Since we live in an rural area with lots of agriculture, what effect does this article have on our biodiversity? Can we assume results from Europe will have a similar effect here? How would you organize a research study based on the studies the researchers did?

Cheetahs and physics

From: http://news.nationalgeographic.com/news/2013/13/130612-cheetah-speed-hunting-big-cats-animal-science/

This Science News article  and National Geographic article (with an interesting video of cheetahs) covers research done by putting collars with GPS on several wild cheetahs as they engaged in hunts. They were able to measure the top speed, acceleration (and deceleration) as well as their movements as they hunted their prey. They were able to decelerate from 36 mph to 9 mph in three strides so they can change direction easily. The scientists first tested their system on dogs on a beach so they could compare their GPS with the locations of the paw prints left in the sand


Read the articles and comment on the physics of hunting and the predator/prey relationship.

Scar and Simba?

This somewhat disturbing picture is of a male leopard killing and eventually eating a cub. This is a widely known practice, but it had rarely been photographed. The article associated with the picture is from National Geographic and explains why this practice is seen in nature.



Natural selection has been identified (somewhat poorly sometimes) as "survival of the fittest". In this case the genes that are passed on to offspring define an organism's fitness. The leopard is killing the cubs of the females that have the genes of another male so that he can mate with her and pass on his genes. It's pretty gruesome, but that's 'The circle of life'.

Another Instant Egghead - limb regeneration!!!

This Instant Egghead is full of information covered in both biology and AP Biology this year. Point out something that we have covered in the comments section!

Genetically Modified Immune cells?

Think about this. A man with a very specific type of leukemia that kills 60% of the adults who get it gets chemotherapy and it doesn't work. He goes through a more aggressive type of chemotherapy and it doesn't work. It's estimated that his bone marrow is 70% tumor. He goes through a new treatment and in 8 days the cancer is gone! GONE!!

This was an experimental treatment against a very specific type of leukemia, but it holds promise for many things in the future.

"...a type of immune cell called T cells are extracted from a patient, genetically modified, and then reinfused back. In this case, the T cells were engineered to express a receptor for a protein on other immune cells, known as B cells, found in both healthy and cancerous tissue."

They used a virus to transfer the B cell marker protein (name tag) so that they T cells would attack and kill the B cells. It is using our own immune system to fight the cancer. This very well could be the wave of the future.

"Four of the five patients subsequently received additional therapy in the form of a bone marrow transplant, the standard of care for those patients who successfully achieve complete cancer remissions after treatment for relapsed disease. To date, three of the four patients have remained in remission for between five and 24 months. One patient died from complications unrelated to the cancer therapy while in remission."

Monoculture CORN

This essay reprinted from Ensia.com and linked to the Scientific American website identifies some of the positives and negatives of the midwest U.S. having the monoculture of corn. We recently had a visitor from the UN help us learn about biodiversity and will soon begin a unit on Ecology.

Use that information and comment on what you think about their opinion (some of which I share and some of which I don't).

Dengue Fever - a little bit of everything!

This video clip has a little bit of everything we have covered thus far this year. It's about how dengue fever enters the cell and creates new copies of itself.

Comment upon something you learned in class this year that was covered in the video.

It's freezing in here!

The wood frog (Rana sylvatica) has the ability to freeze solid and then come back to life upon thawing. This video clip shows the process.



There are other organisms other than the wood frog that also have this ability. This article from The Scientist gives other examples and explains how this works and how scientists are looking to use this ability with humans

Comment on how scientists can use this information to improve human life and health. Also comment upon this affects the characteristic of life of homeostasis. We also discussed transport of water by osmosis and sugar by active transport and facilitated diffusion. What do these have to do with this adaptation?

Evolution of the common cold

The common cold is caused by a rhinovirus which uses RNA as genetic material instead of DNA. The use of RNA allows for a higher mutation rate which causes for more adaptation. This article from The Scientist goes into great detail about these topics.

Read the article and comment on the connection between enteroviruses and rhinoviruses. Also look at how the rhinoviruses use different receptor proteins to enter the cells.

Evolved for the high elevation and cold!!!

These two articles highlight that humans show evidence of natural selection. The Tibetans and those who live in high elevations show genetic changes in their ability to carry oxygen. Native Siberian populations show changes in their genes to adapt to colder temperatures and better maintain homeostasis in the frigid temperatures.

"identified one previously known cold-adaptive gene, UCP1, which helps body fat directly produce heat, as well as two new genes: PRKG1, which is involved in preventing heat loss, and ENPP7, which plays a role in metabolizing fats."

What do you think of these adaptations? What other populations or regions should scientists look for other differences in maintaining homeostasis?