Cell bio Chapter 7 DNA

Genetic Code

The program of the cell.
Heredity is determined by it.

Who first discovered DNA?

Johann Friedrich Miescher 1869

Frederick Griffith Mouse Experiment

injected pneumonia bacteria into mice

result of Frederick mouse transformation experiiment

We learned that when you have a dead set of bacteria the new bacteria can come in and take DNA from the old bacteria and include it in its genetic code.

cell transformation

a cell takes in DNA from outside the cell

Avery,McCarty and Macleod

Identified DNA as the transforming principle by doing many experiments to isolate all the variables

Hershey & Chase

Used radioactive material to label DNA and protein; infected bacteria passed on DNA; helped prove that DNA is genetic material not proteins

Nucleic acids control

cells

What are the four bases of DNA?

Adenine, Thymine, Cytosine, Guanine

Purines

Adenine and Guanine

Pryimidines

Cytosine and Thymine

Purines have ____ rings

two

Pyrimidines have ___ rings

one

Erwin Chargaff

(Father of base pairings) Discovered that DNA composition varies, but the amount of adenine is always the same as thymine and the amount of cytosine is always the same as guanine.

Rosalind Franklin

Woman who generated x-ray images of DNA, she povided Watson and Crick with key data about DNA

Watson and Crick

Developed the double helix model of DNA.

Guaine goes to

Cytocine

Adenine goes to

Thymine

if base pairs are incorrectly formed it causes...

mutation

Each full turn is ___ base pairs.

10

(ex. AAG) 3 base codes a....

amino acid

Waston-Crick Model

DNA consists of two long chains of subunits (nucleotides), each twisted around to form a double helix.

Helicase

An enzyme that untwists the double helix of DNA at the replication forks.

DNA polymerase

An enzyme that catalyzes the formation of the DNA molecule.

semiconservative replication

Method of DNA replication in which parental strands separate, act as templates, and produce molecules of DNA with one parental DNA strand and one new DNA strand

Misreads in replication can lead to....

mutation and death

RNA is diffrent from DNA beacuse of....

1. it uses Ribose surgar
2. Single stranded vrs double stranded
3. Uracil replaces Thyamine

RNA structure

Guanine, uracil, cytosine, adenine. (one strand)

How is RNA made?

DNA transcription

mRNA

messenger RNA; type of RNA that carries instructions from DNA in the nucleus to the ribosome

RNA makes proteins by

translation

20 amino acids make a _____.

protein

every 3 letters codes a

amino acid

protein synthesis process steps

Every three letters of RNA create a

codon

The "start" code for mRNA is

AUG

the "Stop" code for mRNA is

UAA, UAG, UGA

Ribosomes make protein from.....

mRNA that has attached to it

tRNA acts as

interpreters

Each tRNA has a(n) ______ at one end and carries a specific ______ at the other end.

anticodon, amino acid

Ribosomes build polypeptides

the final component that places mRNA and tRNA close together and catalyze the synthesis of polypeptides
made of proteins and ribosomal RNA

Flow of genetic information

DNA -> RNA -> Protein

Translation types

Translation types p2