Bio 120 -Molecular Biology

What are genetic materials DNA features in relation to its structure DNA replication

Characteristics of genetic materials

• Replicates

• Stores information (cells/body organisms)

• Information Expression

• Variation by mutation

What are the two constituents of the nucleus?

• Proteins

• Nucleic Acid

What two experiments confirmed that genetic material was DNA?

1. Prokaryotic bacterium transformation

2. The Hershey-Chase

Explain the Prokaryotic bacterium transformation experiment

A Streptococcus pneumoniae was injected into mice ( deadly)

• Smooth Strain: had polysaccharides coat to protects himself from the host’s immune system

• Rough Strain:no coating

  1. the mice dies from S and survived from R

  2. Heat killed S bacteria from temperature

  3. Injected both types of cells into mouse with heat so they both die but mice survived

Explain The Hershey-Chase Experiments

Bacteriophage Infection

• Used a T2 virus that infects bacteria. It has a outer protein coat that contained DNA

• It infected the bacteria by injection from the legs

What are nucleic acids?

Polymers including DNA and RNA

Structure of nucleotide

1. nitrogenous base

2. pentose (a five carbon sugar)

3. phosphate group

What are the two types of nitrogen bases?

• Purines

• Pyrimidines

Purines consists of…

• adenine

• guanine

Pyrimidines consist of…

• Cytosine

• Thymine

• Uracli (RNA)

Difference between nucleoside and nucleotide

Example:A

…side:adenosine

…tide:adenylic acid

How is the DNA sequence read/ polimerized?

From the 5’ end to the 3’end

What is the component of the 3’-end?

It contains a hydroxide

What is said about the amount of nitrogenous bases in the DNA?

• Amount of A=T

• Amount of C=G

What did the x-ray crystallography demonstrate?

The DNA molecule is a helix

Nitogeous bases connect to stands in the middle though hydrogen bonds

_________________ connect to strands in the middle through hydrogen bonds.

Answer: Nitrogenous bases

What is the backbone of the DNA strand?

Sugar-phosphate linked end to end through through phosphodiester bonds

Describe the structure of RNA

• Single strand polynucleotide

• Uracil replaces thymine

• Uses ribose ( two hydroxyl groups) instead of deoxyribose

What are the three types of RNA?

• Messenger RNA

• Transfer RNA

• Ribosome RNA

What is a messenger RNA?

mRNA

Turns on protein synthesis information by carrying the transcription of genes to the ribosome

What is transfer RNA?

tRNA

Reads information/interprets from nucleic acid into protein language that recognizes specific codons for amino acid production

What is ribosome RNA?

rRNA

Most abundant type of RNA

Forms the structure of ribosomes with other proteins