1 / 11

DNA Structure: The Double Helix

Explore the basic subunit of DNA, the nucleotide, composed of deoxyribose sugar, phosphate group, and nitrogen base (Adenine, Guanine, Thymine, Cytosine). Discover how DNA's double helix structure is formed with complimentary base pairing and anti-parallel strands. Enhance your knowledge with key readings on DNA and RNA as nucleic acids.

nlaroche
Download Presentation

DNA Structure: The Double Helix

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. DNA Structure

  2. ·The basic subunit of DNA is a nucleotide ·Each nucleotide consists of three parts: ·Deoxyribose sugar ·Phosphate group ·Nitrogen base

  3. ·There are four different types of nitrogen bases ·Adenine ·Guanine ·Thymine ·Cytosine pyridimine purine

  4. ·DNA consists of two strands that together look like a ladder This shape is called a Double Helix ·The “backbone” of the helix is formed when the phosphate groups and deoxyribose sugars bond together covalently ·Result is an alternation of sugar and phosphate

  5. ·The nitrogen bases bond together in a pattern called complimentary base pairing to form the “rungs” of the DNA ladder -Adenine always binds with Thyamine -Cytosine always binds with Guanine ·The bases bond together using hydrogen bonds

  6. The two strands of DNA run “anti-parallel” to each other, • This means that the sugar and phosphates run in opposite directions (one looks upside down) • Each side has a 3’ end and a 5’ end

  7. If a strand runs from 3’ to 5’ this means that the backbone runs from sugar to phosphate • If a strand runs from 5’ to 3’ the backbone runs from phosphate to sugar

  8. The two antiparallel strands of DNA coil into a double helix structure

  9. ·The double stranded ladder twists into a double helix shape Homework: Read and add to notes · p 65-68 (DNA and RNA are nucleic acids) ·p 243-251

More Related