Current Events

 

Genes tell old story
Ancient cells hold evidence of a massive die-off of Native Americans
http://www.sciencenewsforkids.org/2011/12/genes-tell-old-story/

                                                                      Stephen Ornes

 Jovana Curcic 8B

First of all, a short introduction about Genetics: 

As we learned about DNA and Genetics throughout this unit, cells make up every part of our body- and in those cells there is DNA, which can be up to 3 meters long, but that DNA squishes and becomes a tiny speck which we can barely even see with microscopes. Humans also have genes, which determine the person’s appearance and attributes, how tall or short he is, skin, hair and eye color, etc. Those genes can be inherited (which means someone could have gotten them from older relatives) and some people can be carriers and carry those genes with them - which doesn’t necessarily mean that those genes are visible.

This article talks about the discovery in the genes that has approved that the arrival of Europeans settlers to undiscovered countries has brought diseases to the native population, which died of new diseases that came along with the settlers. The data found in the ancient cells have just approved the things they already know from the  500 year old documents that recorded the same things, but now they found even more evidence of this discovery. This data has approved that the population of Native Americans have been drastically decreased when the Europeans moved and colonized from Europe to North America. Scientists discovered that as soon as the Europeans arrived to the new continent, the Native Americans started dying because of their diseases (smallpox infections). Scientists used statistics (which involve mathematical studies) to determine how much of the population of Native Americans has experienced death after the Europeans' arrival. The contrast showed the number of people who died. 

I believe this article has approved what we are faced with every day – extinction of species is happening all over the world, not only in plants and animals but in the human population too! Also, this discovery has made me realize what a small world we live in – a place where everything is influenced and connected!

Onion Root Lab

Onion Root Tip lab

Purpose: What proportion of cells is within each phase in mitosis? Make a graph 

Guiding Question: Approximately how much time do cells spend in each phase of the cell cycle?

Hypothesis: We think it will take about the same time for each phase to spend in the cell cycle. 

Materials: Computer, Notebook + Pencils and erasers

Procedure: Perform the onion root tip simulation and tabulate the number of cells in each phase. Construct an appropriate graph using your data to present the relative time a cell spends in each phase of the cell cycle.