Provides thought provoking questions making you think a little harder than the usual questions. Difficulty level: Hard
There are questions on bonds, comparing sizes of different components of DNA, calculations questions and more...
DNA Structure
1 Fig. 5.1.1 below represents a piece of DNA (deoxyribonucleic acid).
a) Colour the sugars, phosphates, adenine, thymine, guanine and cytosine in colours of your choice and
label them.
Use information in your textbook to help you do this.
b) Draw a box around ONE nucleotide and label it
You should have included a base, a sugar and a phosphate.
c) Label a hydrogen bond
Use information in your textbook to help you do this.
2 Write a description of the structure of DNA. Make sure that you use the following key words in your
description.
DNA is a large molecule. It is a polymer or polynucleotide, made of repeating units, or monomers,
called nucleotides. Each nucleotide consists of a pentose sugar, deoxyribose, a phosphate and a
nitrogen-containing base. The bases are the purines adenine and guanine, and the pyrimidines
cytosine and thymine.
The nucleotides are joined in such a way that the large DNA molecule has two anti-parallel sugar-
phosphate ribbon chains as the backbone. There are phosphodiester bonds, which are covalent bonds,
between the sugar and phosphate groups. One chain runs 3` to 5` and the other runs 5` to 3`.
Slung between these ribbon chains, like rungs if a ladder, are the pairs of bases. A purine (2-ring
structure) always pairs with a pyrimidine(1-ring structure) so that the rungs are of the same width.
These bases pair up according to complementary base-pair ruling, adenine with thymine and guanine
1
The benefits of buying summaries with Stuvia:
Guaranteed quality through customer reviews
Stuvia customers have reviewed more than 700,000 summaries. This how you know that you are buying the best documents.
Quick and easy check-out
You can quickly pay through credit card or Stuvia-credit for the summaries. There is no membership needed.
Focus on what matters
Your fellow students write the study notes themselves, which is why the documents are always reliable and up-to-date. This ensures you quickly get to the core!
Frequently asked questions
What do I get when I buy this document?
You get a PDF, available immediately after your purchase. The purchased document is accessible anytime, anywhere and indefinitely through your profile.
Satisfaction guarantee: how does it work?
Our satisfaction guarantee ensures that you always find a study document that suits you well. You fill out a form, and our customer service team takes care of the rest.
Who am I buying these notes from?
Stuvia is a marketplace, so you are not buying this document from us, but from seller tanyam636. Stuvia facilitates payment to the seller.
Will I be stuck with a subscription?
No, you only buy these notes for $13.57. You're not tied to anything after your purchase.
