Structures Of Nucleotides Flashcards
What are the 3 components of a nucleotide?
- a phosphate group
- a pentose sugar
- an organic nitrogenous base
What are the two types of organic nitrogenous base?
- Pyrimidine (single ring)
- Purine (double ring)
Name the pyrimidines
- Thymine
- Cytosine
- Uracil
Name the purines
- Adenine
- Guanine
Where is DNA found?
It’s found as chromatin in the nucleus of eukaryotic cells, and small amounts are found in mitochondria and chloroplasts
What are the functions of DNA?
- It carries the genetic code for protein synthesis
- It replicates in dividing cells
What does DNA consist of?
Two polynucleotide strands twisted into a double helix
What do DNA nucleotides contain?
Deoxyribose, a phosphate group and one of 4 organic nitrogenous bases: adenine, thymine, guanine, cytosine
What are the 2 strands of DNA said to be?
Antiparallel
What do the 2 sugar-phosphate backbones do?
They protect the genetic information stored within the sequence of bases
How are bases held together in DNA?
Hydrogen bonds
What are the complementary base pairs in DNA and how many hydrogen bonds do they form?
Guanine+Cytosine - 3 hydrogen bonds
Adenine+Thymine - 2 hydrogen bonds
Where is RNA found?
Mainly in cytoplasm. Also in nucleus.
How many strands does RNA consist of?
RNA is a single stranded polynucleotide
What pentose sugar does RNA contain?
Ribose