Scale of Everything

If you’ve seen the powers of 10 video you will certainly enjoy this interactive animation that literally covers the scale of everything.  So quick go to this site right now and enjoy it.  Going all the way from the planck length to the width of the observable universe this is not something you want to miss.

I took a break from studying for my upcoming practice finals week to post this because I was so impressed so I hope it’s enjoyable.  I had a test today (Friday) and another four tests in the next four days of class.  I also have a paper due Monday and all the psychology recitation stuff due on Wednesday.  Isn’t it awesome when every class you’re taking decides to have the first round of tests the same week?

 

Flu Shot

I got a free flu shot today at health services just by showing my student I’d.  It’s hard to beat free and there’s really no reason not to get a flu shot.  The shot contains three inoculated stains of the influenza virus that the CDC expects to be three most prevalent this year based on infection trends.  With an inoculated or dead virus there is no risk of getting the flu directly from the vaccine.  Minor swelling or irritation at the injection site is due to the shot and not actually why infection from the virus.

Interestingly, the nasal flu mist vaccine contains a weakened instead of inactivated virus.  This is probably because there would otherwise be no immune reaction to the inactivated virus when sprayed into the nose. 

Human Genome

The human genome is composed to 23 chromosome pairs and enough DNA to stretch 2m when put end to end, but did you know what we have relatively little idea what the purpose of 98% of that DNA really is?

The 23,000 protein encoding genes in the human genome make up only 2% of our DNA.  Of those 23,000 genes, we only understand the function of about half of them.  Another 3.5% of our DNA is non-coding DNA that we share with mice and rats, but whose function is unknown.

We have a long way to go until we truly understand ourselves at the molecular level.  The human genome has been said to have been sequenced, but in reality, parts are still incomplete because of difficulties in sequencing.  What is more, even parts that are sequenced have yet to be studied in detail.  Only being able to understand 50% of the coding genes in our genome may give us some understanding, but when we get to a more complete understanding it’s going to be revolutionary.

[Source]

DNA

I read something in Scientific American about how all the DNA in the human body put end to end would stretch to the sun and back again to earth over 100 times.  I don’t know about the math of the article’s author but it reminded me of a calculation I had done in AP biology during junior year of high school.

From the textbook it was given that there are:

• 2m of DNA in every human cell when entirely uncoiled.
• 50 Trillion cells estimated in the average human body
• 1/4 of cells are red blood cells and thus do not have a nucleus or DNA, so that leaves approximately 37.5 trillion cells
• 152,098,232 km =  Maximum distance of Earth from the sun
• 7,375,927,931 km = Maximum distance of Pluto from the sun
• 2 x 7,375,927,931 km = 14,750,000,000 km Diameter of the solar system

So 2m DNA/cell x 37,500,000,000,000 cells = 75,000,000,000,000 = 7.5 x 10^13 m = 7.5 x 10^10 km of DNA when totally uncoiled and aligned end to end.

7.5 x 10^10 km / 152,098,232 km = 493  times to the sun and back

7.5 x 10^10 km / 14,750,000,000 km = 5 times across the diameter of the solar system.

That’s an incredible distance to be coiled up within all the cells of your body!  2m of DNA per cell is incredible in itself, but count in the number of cells and it’s literally an astronomical distance.

 

 

Human Population

As the number of humans on planet Earth surpasses 7 billion, take a moment to reflect back.  I thought about how much the world has changed when I recently heard that when Kennedy was elected President of the United States there were only half as many people on earth.  In 1960, the world population was 3 billion.  Only 40 years later around the year 2000, world population doubled to hit 6 billion.  In the 10 years since then, world population has increased by another billion.

Water Molecules: Visualization through a Glass of Water

There are approximately 1,386,000,000 km³ of water contained on, under and above the surface (source).  Incredibly, however, there are more molecules of water in a single 8 oz. glass of water than there are glasses of water on the planet.

We assume a typical glass of water is 8 fluid oz., the molar mass of water to be 18.015  g/mol, the density of water is 1.00 g/mL and avogadro’s number (the number of molecules in a mole) to be 6.022 x 10²³

8 fluid oz. H2O =  0.23659 L H2O

0.23659 L H2O = 236.59 g H2O

236.59 g H2O/18.015 g/mol = 13.133 mol H2O

13.133 mol x 6.022 x 10²³ molecules/mol = 7.9086 x 10²⁴ water molecules

1,386,000,000 km³ H2O =  1,386,000,000,000,000,000,000 m³ H2O

1,386,000,000,000,000,000,000 m³ H2O = 1.386 x 10²¹ m³ H20

1.386 x 10²¹ m³ H20 = 4.6866 x 10²⁵ fluid oz.

4.6866 x 10²⁵ fluid oz. / 8 oz. per glass = 5.858 x 10²⁴ glasses of water

5.858 x 10²⁴ glasses of water < 7.9086 x 10²⁴ water molecules

So by my math, there are more water molecules in a single glass of water than there are glasses of water on the entire planet.

Acceleration due to Gravity

If you were hypothetically able to accelerate at the rate of earth’s gravity (9.8 m/s^2) for a year you would be moving faster than the speed of light relative to your initial frame of reference.

(Note: Nothing can achieve a speed faster than the speed of light.)

(9.8 m/s^2)(60s/min)(60min/hr)(24hr/day)(365days/year) = 309,052,800m/s

Speed of light: 299,792,458m/s

Wow.