What do Genes Look Like? Chapter 7, section 1 notes

- Hereditary material that controls the activity of a cell. What we know: Genes are located on chromosomes and chromosomes are made of DNA. DNA - Hereditary material that controls the activity of a cell. - Contains information to make new cells. - Provides instructions for making protein.

DNA serves two main functions To supply complex instructions for cell processes and for building cell structures. To be able to be copied each time a cell divides.

Let’s take a look inside… How can something so small hold the keys for making and directing living organisms? Let’s take a look inside…

Nucleotides- the subunits of DNA 4 nucleotides make up DNA 1.  Adenine 2.  Thymine 3.  Guanine 4. Cytosine

3 different types of materials make up a nucleotide 1.  Sugar 2.  Phosphate 3. Base

The People involved Erwin Chargaff- Chargaff’s Rule- A = T and G = C Mnemonic Device  Atoms are Tiny (adenine pairs with thymine) Candy is Great (cytosine pairs with guanine)

Rosalind Franklin She used x-ray diffraction to capture an image of a DNA molecule that suggested that DNA has a spiral shape.

James Watson and Francis Crick Took the information from Wilkins and Franklin and concluded that DNA resembles a twisted ladder shape known as a double helix. They used this model to predict how DNA is copied.

Notes on your own… DNA’s Double Structure (pg. 210) DNA Replication (pg. 210) How Copies Are Made (pg. 211) When Copies Are Made (pg. 211) For each sub heading write down three or four important facts. Also draw a sketch to model how DNA is replicated.