DNA is made of Nucleotides (p. 282). Nitrogen Bases.

DNA is made of Nucleotides (p. 282)

Nitrogen Bases

DNA Fingerprinting• I. DNA is collected from usually blood, semen, or hair

– Restrictive enzymes cut the DNA at specific sites– The cut up DNA is then placed in an agarose gel in a pan– Electrophoresis

• Using an electric current to separate DNA Strands• Short strands migrate through the gel easier than the long strands

do. – Thus, short strands go further through the gel

– A DNA fingerprint is made.– Look at the following site to complete the simulated DNA

fingerprint:– http

://www.pbslearningmedia.org/asset/tdc02_int_creatednafp2/?utm_source=teachersdomain_redirect/asset/tdc02_int_creatednafp2/utm_medium=teachersdomain/asset/tdc02_int_creatednafp2/utm_campaign=td_redirects

Purpose of DNA Replication

• I. DNA Replication (p. 285)–A. DNA is copied• 1. Happens before a cell divides• 2. Without DNA replication, new cells would

only have half the DNA of the original cell• 3. Steps of replication– a. Separation of strands– b. Base Pairing (Free floating nucleotides pair up)

• 4. Results of replication– a. 2 new molecules of DNA– b. Each new molecule has 1 original strand and 1

new strand

Mitosis

A.B.C.D.

Correct Way

Wrong Way