You are a molecular biologist brought into consult for NASA on some strange samp

Question

You are a molecular biologist brought into consult for NASA on some strange samples. These samples appear to be new life forms that contain carbohydrate polymers. You are an expert on glucose polymers...but it appears that these new cells use polymers of ribose.

There are three polymers:
1) The first polymer is bonded from the 1' carbon on one ribose to the 3' carbon on the next (and repeating)
2) The second polymer is bonded from the 1' carbon on one ribose to the 4' carbon on the next. This polymer also has occassional bonds between the 3' carbon of a ribose and the 1' carbon on the next. There are about 10 of the 1'-to-4' bonds for every 1'-to-3' carbon.
3) The third polymer appears to have bonds between the 1' and 4' carbons, and also between the 5' and 2' carbons. The 5'-to-2' polymers are only 3-4 monomers long before they bond to a different 1'-to-4' polymer.

First, NASA asks you to sketch these polymers to give yourself a guide for what they look like.

Then, NASA tells you that one of these polymers is used for protection of this new organism. Another polymer is used for energy storage in a very small cell. The third polymer, well, they don't know what that is for.

Describe which polymer is for which of these two purposes, and why you think this. Also, postulate a role for the third polymer.

Explanation / Answer

NASA tells you that one of these polymers is used for protection of this new organism. #2

#2  The second polymer is bonded from the 1' carbon on one ribose to the 4' carbon on the next. This polymer also has occassional bonds between the 3' carbon of a ribose and the 1' carbon on the next. There are about 10 of the 1'-to-4' bonds for every 1'-to-3' carbon.

#2 has the strongest bonds, which will allow it to bind to a different 1' to 3' polymer for the most durable protection.

Another polymer is used for energy storage in a very small cell. #1

#1) The first polymer is bonded from the 1' carbon on one ribose to the 3' carbon on the next (and repeating

Simple sugar storage - the repetition of the Ribose/Carbon is a "simple" way for the small cell to store "simple" sugars for quick and easy access.

Smaller cells prefer simple sugars - easier to digest for their small, immediate needs.

The third polymer, well, they don't know what that is for. #3

#3) The third polymer appears to have bonds between the 1' and 4' carbons, and also betweenthe 5' and 2' carbons. The 5'-to-2' polymers are only 3-4 monomers long before they bond to a different 1'-to-4' polymer.

#3 might be used for communicating with other cells - there are few monomers (obv. not food storage) but bonding to a different polymer will facilitate communication of products (i.e. water) :)

Related Questions

Navigate

• Browse (All)
• Browse Y
• Subjects

---

---

Integrity-first tutoring: explanations and feedback only — we do not complete graded work. Learn more.