CELLS & DNA
One cannot talk about cells without spending time discussing DNA. The current TCAP
assesses DNA through talking about heredity and inheritance. It ask questions asking
students to identify outcomes which could or could not be the result of things inherited
through DNA. For example, freckles....yes. Hair color and eye color, yes. DNA controls
what is inherited.
Although DNA is not currently assessed, I believe it will be more in Common Core, as it
is a fundamental process of biology.
Inheritance. Each human parent provides 23 chromosomes. These chromosomes line
up and make many quick decisions about the person. Bald or not bald. Red hair or not
red hair.
http://www.pbs.org/wgbh/nova/body/extract-your-dna.html
http://learn.genetics.utah.edu/content/labs/extraction/howto/
Math Problem 4
Ronnie, Jenny and D’Arcy are sitting in the cafeteria telling tall tales. They have
been studying DNA in science class, and understand that it is in a coil. Ronnie
brags that his DNA would stretch all the way across Tennessee if it were
uncoiled. Jenny says, “ That’s nothing! My DNA would stretch from Earth to the
Moon!” “You think that’s special?” D’Arcy brags. “My DNA would stretch out
from the Earth to the Sun. Take that!”
Which of these braggarts is telling the truth? A body has 100 trillion cells. That’s
100,000,000,000,000. Each cell has 6 feet of DNA in the nucleus if the DNA is
stretched out.
Tennessee is 420 miles from east to west. It is 238,000 miles from Earth to the
Moon. It is 93,000,000 miles from Earth to the Sun.