What is a single molecule of DNA composed of?
- 2 long strands of nucleotides
- Double helix structure
Nucleotides are the subunits that make up DNA.
Each nucleotide is made of how many distinct chemical components?
3
The components are deoxyribose sugar, negatively charged phosphate group, and nitrogenous base.
List the components of a nucleotide.
- Deoxyribose sugar
- Negatively charged phosphate group
- Nitrogenous base
The nitrogenous bases include adenine (A), thymine (T), cytosine (C), and guanine (G).
What does A stand for in nitrogenous bases?
Adenine
The other bases are Thymine (T), Cytosine (C), and Guanine (G).
What do chromosomes contain?
- Genes
Genes are sections of DNA that code for various traits and characteristics.
What do genes code for?
- Height
- Eye color
- Ability to roll tongue
- Predisposition to some illnesses
Genes determine many physical and health-related traits.
What is found between genes in DNA?
Non-coding DNA
This DNA does not code for anything beneficial or harmful and varies among individuals.
What are short tandem repeats?
- Repeated sequences of DNA
- Vary in length among individuals
They are used in DNA profiling and forensic analysis.
How can we separate segments of DNA?
Using gel electrophoresis
This technique allows for the comparison of short tandem repeats.
What does the triphosphate group do in a nucleotide?
Gives structure to the molecule
It is negatively charged and plays a role in the stability of DNA.
How do nitrogenous bases bond in DNA?
Via hydrogen bonds
The bonding occurs between complementary bases: A with T and C with G.
What connects the phosphate group and nitrogenous bases in a nucleotide?
Deoxyribose sugar
This sugar is essential for the structure of DNA.
What does Polymerase chain reaction (PCR) do?
Copies a portion of DNA into millions to billions of copies
Used when you have trace amounts of DNA to accurately profile it.
What is the temperature range for Denaturation in PCR?
Approximately 90-95 degrees
This process results in single stranded DNA.
What occurs during the Annealing step of PCR?
- DNA is cooled to 50-55 degrees
- Primers bind to complementary sequences on the single strand DNA
This step is crucial for the primers to attach properly.
What is the temperature for the Extension step in PCR?
72 degrees
A new strand of DNA is synthesized during this step.
