Basic Genetics Homework

By going on http://learn.genetics.utah.edu/ , I learned many things about heredity and traits. First, I learned that a trait is a notable quality in a person. Each of us possesses a different combination of traits that makes us unique. Traits are passed from generation to generation. We inherit traits from our parents and pass them down to our children. I also learned that heredity is the passing of traits from parents to child. Children look like their parents because we "inherit" some of their traits. Our genes are made of DNA and they live in our chromosomes. We all have thousands of genes and the environment we grow in, as well as our genes, help define our traits. Humans have two complete sets of 23 chromosomes, totaling to 46 chromosomes in our body. When children are born, each parent contributes one set of chromosomes to the offspring, passing on genes to the child. That is what I learned about heredity and traits by visiting this interesting website.

Science Class Response

Owl Pellet Lab

My favorite class activity was the owl pellet lab. It was interesting to attempt to put together an entire skeleton of an owl's prey. I wasn't too fond of picking out bones from regurgitated owl food. However, analyzing the variety of bones, especially the small ones, was intriguing. It was amazing how putting together an entire skeleton from an owl pellet can show you how the owl's prey looked while it was alive. I enjoyed learning about owl pellets and dissecting owl pellets. Overall, this activity was very educational and fun, and I hope to do another activity like this again during the year.

Initially, before doing this lab, I thought that an owl pellet was just excreted waste. However, now, after studying owl pellets, I know that an owl pellet is a mass of bone, teeth, hair, feathers, and exoskeletons of the prey of the owl. Since owls don't have fingers and can't pick apart bones and fur from flesh, they swallow their food whole. Bones and feathers can't be digested by owls, just like with humans, therefore, the gizzard filters out the indigestible parts of the food. Several hours later, they are compressed into an owl pellet and are regurgitated when the digestive system has finished extracting the nutrition from the food. I found these facts interesting because they show the similarities and differences between owls and humans, and they display what all owls have to do just, because they don't have fingers. When I noticed this article posted on Sunny-D's blog, I read this interesting article on another mammal species found because of an owl pellet. The article said that Dave Tosh, from the School of Biological Sciences at Queens University, found the greater white-toothed shrew in Tipperary and Limerick because of some unusual shrew skulls that he found inside a few owl pellets that were sent to him by John Lusby, Barn Owl Research Officer from Bird Watch Ireland. This obviously shows how much you can learn about other animals that are the prey of the owl, just by examining an owl pellet.

http://www.sciencedaily.com/releases/2008/04/080428071113.htm

Science Current Event #2

Are Wolves the Pronghorn's Best Friend?

As of 2008, the Wildlife Conservation Society has made a new study that cautions that removing the gray wolf from the protection of the Endangered Species Act may result in a decline in the pronghorn species. Since wolves are larger than coyotes, they decrease coyote numbers by either killing them or by causing them to shift to safer areas which are not inhabited by wolves. Healthy wolf packs balance out the coyote population, and the fewer the coyotes, the more pronghorns because coyotes and pronghorns have a predation relationship. Wolves are too big to feed on pronghorns themselves, since a small pronghorn won’t satisfy their empty stomachs. The wolves feed on coyotes, providing themselves with food, and reducing the amount of predators for the pronghorns.

Therefore, I think that in a way, wolves are the pronghorn’s best friend. The relationship between the pronghorns and the wolves is commensalism, a type of symbiosis that benefits one animal and does not affect the other. This is because when wolves eliminate some of the major predators of the pronghorn, its population increases since they have a longer life due to their greater chance of survival. I think that the gray wolf is safe to be removed from protection under the Endangered Species Act because their reproduction rate is increasing, as well as the gray wolf population. It will not necessarily impact the pronghorn population because the amount of gray wolves is not decreasing. If an unexpected drop in the wolf population does occur, then the gray wolf should immediately become protected by the Endangered Species Act again. Otherwise, as the Wildlife Conservation Society predicted, there could be a decline in the population of the pronghorn species. Therefore, unless a drastic drop in the wolf population occurs, I think that it is safe to remove them from protection under the Endangered Species Act.

http://www.sciencedaily.com/releases/2008/03/080303145300.htm