Reduce, Reuse, Recycle

This question is in anticipation of Earth Day, April 22. Does that give you a hint towards the correct answer? By depositing cut grass back onto the soil, homeowners are (2) recycling nutrients. This cut grass will decay, and nutrients from these cut pieces will find their way back to the soil. Recycling! By bagging those clippings and throwing them away, we'd waste nutrients that could be reused again.

This process does not (1) increase the diversity of life, does not control (3) pathogens or pests, and does not (4) produce any new species. By process of elimination, the correct answer is 2.

*Question taken from nyslivingenvironment.net, from August 2008 Regents

After a Nice Break, the Regents Return...

Hey everyone, hope you all had a nice and relaxing vacation, and that you're ready to get back into the swing of things...I know how much you all have missed practicing those regents questions. But science is cool! At least, Robert Downey Jr. and Mark Ruffalo think so.

In any case, my old favorite website nyslivingenvironment.net seems to have been shut down, hopefully temporarily, so this one is from regentsprep.org.

Which is a biotic factor operating within an ecosystem?

1. the type of climate in a given region
2. the carnivores that consume other animals
3. the amount of helium gas in the air
4. the rate of flow of water in a river

The correct answer here is 2. Biotic means living, and abiotic means nonliving. Climate, helium gas, and water are all nonliving, while carnivores are indeed alive. Biotic also refers to organisms that were once alive.

Test out your skills with this quiz...remember, biotic refers to organisms that are alive/were once alive. http://www.quia.com/quiz/244317.html

A Regents Question A Day...

This question was taken from the August 2008 exam, question # 19 (nyslivingenvironment.net). Reproduction is defined as the production of offspring. Sexual reproduction involves two organisms DNA combining, while asexual reproduction involves only a single organism, which creates genetically identical offspring. In this picture, how many organisms are involved? One. Bonus points for this question (answer in the comment box): Once this stem is cut and put into water, what is the name of the process by which it grows?


This whole process is pretty cool, if you think about it. If you want to make more than one plant, depending on the type of plant, all you have to do is cut the stem and put it in water and, voila! Did you know you can grow some vegetables like this? Carrots, for example, do reproduce sexually (they have seeds that you plant, with DNA from two parents), but you can also "clone" a carrot, by cutting the top off (keeping the greens on), putting it in a cup of water with a clear bag on top, covering, and letting the roots grow. Once the roots have grown and new green begins to form, you can plant your carrots in the ground and let them grow again naturally.

(photo taken from http://www.photoree.com/photos/permalink/762557-62545923@N00)

Snowy Day Post

Hello everyone, hope that your snowy, slushy, rainy day today wasn't too terrible. Maybe a regents question will brighten it up? :) This one is a no brainer anyway, and actually very relevant to you, me, and the world around us. So, here goes.

 This is question #24 taken from the August 2008 regents (taken from nyslivingenvironment.net):
 

The correct answer here is (1), human actions are a threat to equilibrium in ecosystems. The key to this question lies in simply following the arrows. In fact, you could answer it without knowing that the term "equilibrium" here refers to the balance of an ecosystem. If you follow the arrows and read, the question ends up sounding something like this: "Humans modify ecosystems through technology, consumption, and population growth. This disrupts equilibrium in ecosystems." Knowing this, the other 3 options don't make sense. Got it?!

This questions brings up some issues that we are all going to have to deal with at some point in our lives. Our technology, our consumption, and our growing population have caused a great disturbance in our ecosystem (earth), which did not exist even 100 years ago. Advances in technology have allowed us to consume more and use more resources. Think about it. We fly planes, drive cars, construct buildings, build computers. We do what we want, when we want. In addition, our growing population means more resources must be used to feed this population--how does this effect the world around us? Will more land have to be put aside for farming? How can we grow more food efficiently without using pesticides and chemicals? Is it possible to feed a population that's growing so fast without using these chemicals? What about climate? How do our actions change the weather around us?

If you're a little lost, here's a video that will put you in the right mindset:
 http://www.brainpop.com/science/ourfragileenvironment/globalwarming/

This website has great examples of the "human footprint," or our mark on planet earth:
http://www.nationalgeographic.com/earthpulse/human-impact.html

Can the state of our current society last forever? Are there unlimited resources here on this earth? What do you think? Can you think of any changes that we should make in our own lives in order to create more of a balance, or disrupt our ecosystem less?

Welcome!

Hello everyone! This is my first blog post, and it is quite exciting. The idea for this webpage is to review Regents questions for the NYS Living Environment Regents. More than explaining why certain answers are right or wrong, I will try to provide links to interactive activities and videos to reinforce and explain specific concepts.

So, let's get started.

This is question #7 taken from the June 2010 exam (nyslivingenvironment.net):



The correct answer here is (2) 35%. DNA is made up of 4 bases: adenine (A), guanine (G), thymine (T), and cytosine (C). Adenine and guanine are known as purines, while thymine and cytosine are pyrimidines. In a DNA molecule, one purine is always paired to one pyrimidine, thus they pair in a 1:1 ratio. Adenine (purine) pairs with thymine (pyrimidine), and guanine (purine) pairs with cytosine (pyrimidine). For every one adenine, there will be one thymine. For every one guanine, there will be one cytosine.

           
A way I was taught to remember the base pairs was with the phrase At Garden City. Garden City is a town near where I grew up, and if you remembered the phrase AT Garden City, you would remember A pairs with T and G pairs with C.

In any case, if we know that a DNA sample is made up of 15% thymine (T), that means it must also be made up of 15% adenine (T). 15% + 15% = 30%. Therefore, the other 70% (100% - 30% = 70%) of the molecule must be made up of guanine (G) and cytosine (C). And if there is an equal amount of both of these bases, we know that 70% must be divided by 2, to get 35% C and 35% G. Make sense?

For more general information on DNA, check out these videos:

http://www.brainpop.com/science/cellularlifeandgenetics/dna/
http://learn.genetics.utah.edu/content/begin/tour/

For more practice, you can build your own DNA molecule here:

http://learn.genetics.utah.edu/content/begin/dna/builddna/