Nucleic Acids Flashcards
What is DNA?
The genetic material of all living organisms
Some viruses use RNA, but viruses are not considered living
What are nucleic acids?
Genetic material of the cell; composed of recurring monomeric units called nucleotides; two types: DNA and RNA
What are the components of a nucleotide?
5-carbon pentose sugar, phosphate group (attached to the 5’– carbon atom), and nitrogenous base (attached to the 1’– carbon atom)
What types of bonds are found in DNA?
Covalent bonds within nucleotides; hydrogen bonds between complementary nucleotides
What is the function of a nucleic acid
- Passes information between generations
- Codes for protein production
Sugar-phosphate backbone
It is antiparallel and shares electrons in a covalent bond between sugar and phosphate to provide strength to the structure
What are Monomers?
- Nucleotides
- Amino Acids
- Simple Sugars (monosaccharides)
- Fatty acids
What are Polymers?
- Nucleic Acids
- Proteins
- Carbohydrates (Polysaccharides)
- Lipids
What is the RNA Condensation Reaction?
Process of changing from monomer to a polymer through dehydration (removal of H2O)
What is Hydrolysis?
Process of changing a polymer to a monomer (addition of H2O)
State the difference between RNA and DNA
DNA
- Double-stranded helix
- 2 sugar-phosphate backbones
- Deoxyribose nucleotides
- A, T, C, G
RNA
- Single-stranded
- 1 sugar-phosphate backbone
- Ribose nucleotides
- A, U, C, G
How is DNA replication started?
One strand is used as a template for a new strand
What is the evidence of common ancestry?
DNA is the genetic material for all living organisms, and the same genetic code has been passed down
What is the most stable bonding between complementary bases? (HL)
Purine - Pyramidine
What is a nucleosome? (HL)
A structural unit of DNA consisting of a molecule of DNA core of eight histone proteins (an octamer)
What is the structure of a nucleosome? (HL)
- DNA is wrapped around 8 core histone proteins
- Negatively charged DNA associates with positively charged amino acids
- Individual nucleosome are together linked by an additional histone protein (H1) attached to linker DNA
What is the function of a nucleosome (HL)
It supercoils DNA to prevent damage and regulates the level of transcriptional activity
What is the N-terminal tail? (HL)
It determines how tight the DNA is packaged
What does the Hershey - Chase Experiment prove?
That DNA is the genetic material (not protein) through radio activating DNA and not protein
Explain the Hershey - Chase Experiment
- DNA had phosphorus radioactively labeled, and Protein had sulfur radioactively labeled
- Radioactive sulfur was put into a centrifuge, but was a supernatant
; Radioactive phosphorus was put into a centrifuge and was a pellet - Pellets indicate that it has larger mass, thus DNA is the genetic material
