A1.2 DNA Flashcards
What are the 4 types of biological molecules upon which life is based?
Lipids
Carbohydrates
Proteins
Nucleic acids
What are the two primary functions of nucleic acids?
- Pass information between generations
- Code for protein production
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What are the two types of nucleic acids?
DNA - Deoxyribonucleic acid
RNA - Ribonucleic acid
What are the two types of nucleic acids?
DNA - Deoxyribonucleic acid
RNA - Ribonucleic acid
What are the three parts of a nucleotide?
Penrose sugar
Phosphate group (negatively charged)
A purine or pyrimidine made nitrogenous bases which are:
- adenine
- thymine
- guanine
- cytosine
- uracil
H group or OH group one pentose sugar?
DNA - H group at end as it lacks an oxygen (deoxyribose)
RNA - OH group (ribose)
What is the nucleus acid and condensation reaction?
Backbone formed through a condensation reaction, where nucleotides combine to form a single molecule resulting in the loss of a water molecule
How is a DNA molecule adapted to carry out its function?
Stability - can pass through generations without change
Hydrogen bonds - allows easy separation of strands
Large molecule - carries vast amounts of information
Helical cylinder - protection from chemical and physical changes
How is a DNA molecule adapted to carry out its function?
Stability - can pass through generations without change
Hydrogen bonds - allows easy separation of strands
Large molecule - carries vast amounts of information
Helical cylinder - protection from chemical and physical changes
Purines and pyrimidines
Always in a 1:1 ratio. The purines are Guanine and Adrenine. A purine has a double ring structure.
The pyrimidines are cytosine, Thymine and Uracil (only in RNA). Single ring structures
Where is DNA and RNA in a eukaryotic and prokaryotic cell?
Eukaryotic
DNA. RNA
nucleus. Nucleus
Mitochondria. Cytoplasm
Chloroplasts
Prokaryotic
DNA. RNA
nucleoid. Cytoplasm
Plasmids
How many possible sequences in DNA?
4^n sequences so a stream of DNA with just 15 nucleotide pairs has 1,073,741,824 possibilities
What was the Hershey-Chase experiment?
By: Alfred Hershey and Martha Chase
Viruses are made of both DNA and protein and DNA contains phosphorus while protein contains sulfur so they added a radioactive isotope of these elements and the radioactive isotope in the host cell which is affected by the bacteriophage (the virus) is the hereditary component.
Which was DNA.
Scientists who found the structure of DNA
Erwin Chargaff - found the pairs are A-T and G-C as they had the ratios of the opposite one for example A had the same ratio as T.
Linus Pauling - came up with a structure which ended up being impossible as there was a clump of phosphates which are all negatively charged so they would repel.
Rosalind Franklin - Took clearest image of DNA after many failed attempts (called photo 51). She also found key things in the structure.
Maurice Wilkens - stole Franklin’s research and gave it to Watson.
Watson and Crick - they out all this research together and came up with a structure which won the Nobel prize
Hershey and Chase - found out DNA is the hereditary and not protein.
