AP Biology 2.4 Evolution
AP Biology 2.4 Evolution. Since the human appendix can be removed without any any ill consequences, many scientists believe it is what?
|Test Prep||AP Biology|
And here are the potential answers: Let’s start with A, homologous structures.
Take a look at your hand. [Man looks at own hand]
You can grab, point, wave, hit, and hold, all with the help of your handy-dandy hand.
That’s how human hands evolved, and it’s a good thing they did…they come in handy [Man gesturing with hand while in traffic]
during rush hour traffic.
…Not that we do that, or anything.
But take a look at this seal. [A seal riding a car]
Not only is this seal a far better driver…his “hands” evolved into flippers, which help
So even though our hands have similar bones, muscles and nerves when compared to seal’s
flippers, they perform different functions.
A seal’s flippers and human hands are examples of homologous structures. [A man and seal dancing]
They have similar anatomy, but different functions.
And considering the appendix can be removed without any ill consequences, we know that
it has no function, so we can eliminate A. So what about “B”?
Biogeography is the study of the distribution of species and ecosystems in different geographic
The last time we checked, the appendix wasn’t occupying any geographic spaces, so we can [Man checking a map for appendix]
safely eliminate B. What about “D,” comparative embryology?
Comparative embryology compares and contrasts the fetal stages of different species.
The Greek philosopher Aristotle is considered to be the world’s first comparative embryologist. [Aristotle appears in a library]
In his writings, Aristotle mentioned “eggs” and “live births,” but surprisingly enough,
never spoke of the appendix…
Not even…in the appendix... [A list of words in an appendix]
Anyway, we can eliminate “D.” Looks like “C” is our answer.
Throughout human evolution, certain organs in the body have lost their original functions.
Look at the tailbone. [A man showing a tail bone]
When our tails fell off, the tailbone became vestigial, or functionless.
It’s a shame, though.
If we still had a tail, we’d always have something to do when we’re bored. [Man chasing a tail]
The appendix suffers the same sad fate as the tailbone.
Good bacteria is stored in the appendix and used to help fight off the effects of dysentery
However, since those ailments are harder to catch these days than the 6:25 a.m. school [School bus arrives]
bus, the appendix has long since lost its function, making it a vestigial organ.
But don’t worry, vestigial organs.
If Simon and Garfunkle can have two comebacks and the Eagles can have five... so can you. [Vestigial organs playing in a band]