DNA Structure and Function James Corcoran

Watson & Crick

James Watson and Francis Crick were two sciencetist who discovered the model of DNA. They said that DNA was a double helix, and they tested models with metal wires in their house. These men were assisted Rosalind Franklin who also helped them develope the model of DNA.

Chargaff's fist rule

Chargaff ’s first rule: the amounts of thymine and adenine are identical, as are the amounts of cytosine and guanine (A = T and G = C). He basically said organisms should have a 1:1 ratio

Chargaffs' second rule

Chargaff ’s second rule: DNA of different species differs in its proportions of adenine and guanine " the amount of guanine is equal to cytosine and the amount of adenine is equal to thymine."

How do base pairs bind

Hydrogen bonds between the internally positioned bases hold the two strands together. Only two kinds of base pairings form (supports Chargaff ’s first rule): A to T & G to C. The base of each nucleotide on one strand pairs with a suitable partner base on the other

What is a chromosome

Chromosome: structure that consists of DNA and associated proteins. Carries part or all of a cell’s genetic information. each chromosome consists of one DNA molecule.


Karyotype: an image of an individual diploid set of chromosomes

How does DNA replicate

Before DNA replication, a chromosome consists of one molecule of DNA (one double helix). As replication begins, enzymes break the hydrogen bonds that hold the double helix together. The two DNA strands unwind and separate.

What'd damages DNA

Replication errors may occur after a cell’s. DNA gets broken or damaged. DNA polymerases do not copy damaged DNA very well . Mutation- a permanent change in the DNA sequence of a cell’s chromosome

Created By
James Corcoran

Made with Adobe Slate

Make your words and images move.

Get Slate

Report Abuse

If you feel that this video content violates the Adobe Terms of Use, you may report this content by filling out this quick form.

To report a Copyright Violation, please follow Section 17 in the Terms of Use.