DNA structure and function

Question 1

Who discovered the structure of DNA?

Answer 1

Rosalind Franklin, Maurice Wilkins, Francis Crick, James Watson
Wilkins took photo 51 without Rosalind’s permission, showed it to Crick and Watson, who discovered the double helical shape of DNA.
Erwin Chargaff used chromatography to discover the nitrogenous bases, helping to discover complimentary pairing.

Question 2

Where is DNA found in Eukaryotes (and what shape in its locations)?

Answer 2

Linear DNA is found bound to proteins in chromosomes within the nucleus of eukaryotic cells.
Circular DNA is found unbound in chloroplasts and mitochondria.

Question 3

Where is DNA found in prokaryotes (and what shape)?

Answer 3

DNA found unbound in nuclei region of the cytosol.

Circular form.

Question 4

What is DNA (deoxyribonucleic acid?

Answer 4

A molecule which contains genetic information (in the form of chemical code) to create proteins by cells. It is capable of creating and maintaining an organism, and can be passed down generations.

Question 5

What is the structure of DNA?

Answer 5

DNA is a double stranded, helical molecule, made up of nucleotides.

Question 6

What are nucleotides made up of?

Answer 6

Five carbon (pentose) deoxyribose sugar, phosphate group, nitrogenous base. These (nucleotides) are the base units of DNA.

Question 7

What is the structure of a nucleotide?

Answer 7

1. ) Phosphate group attached to two pentose sugars through phosphodiester bonds (on 3’ carbon and 5’ carbon)
2. ) Pentose sugar is attached to nitrogenous base through a glycosidic bond
3. ) Nitrogenous base is attached (either with 2 or 3) to another nitrogenous base (based on complementary base pairing)

Question 8

How many hydrogen bonds does Cytosine and Guanine have when paired?

Answer 8

3 hydrogen bonds

Question 9

What are the structural properties of DNA that allow for DNA replication?

Answer 9

• Nucleotide composition
• Base pairing
• Hydrogen bonds

Question 10

How does DNA control growth and development?

Answer 10

• Stores information known as genes (which code for a specific protein/polypeptide, which in turn creates traits)
• Genes can code for more than one polypeptide and interact with each other
• Interaction changes in expression from production of proteins

Question 11

How does the structure of DNA allow it’s function?

Answer 11

1.) It’s structure