Biological Molecules: Structure of DNA and RNA Flashcards
What does the pentagon represent in the structure of a nucleotide?
Pentose sugar
What does the rectangle represent in the structure of a nucleotide?
Base
What does the circle represent in the structure of a nucleotide?
Phosphate group
What bonds form between one nucleotides pentose sugar and another’s phosphate group?
Phosphodiester bond
What bonds form between two nucleotide bases?
Hydrogen
What are the 4 bases of DNA (full names)?
-Adenine
-Thymine
-Cytosine
-Guanine
What are the 5 main features of the structure of DNA?
- Base sequences
- Large
- Double helix
- Sugar-phosphate backbone
- Hydrogen bonds between bases
What are the function of bases sequences in DNA?
Store genetic material
What is the function of DNA being large?
Massive amount of genetic information
What is the role of DNA having a double helix structure?
Compact
What is the role of DNA having sugar-phosphate backbones?
Stability and protection = reduces mutations
What is the role of DNA having hydrogen bonds between its bases?
They can break and reform, allowing replication and protein synthesis
Give three differences between eukaryotic DNA and prokaryotic DNA
1) Eukaryotic DNA contains exons and introns, prokaryotic DNA only has exons
2) Eukaryotic DNA is long and linear, prokaryotic DNA is short and circular
3) Eukaryotic DNA has chromosomes, prokaryotic DNA doesn’t
In RNA what does uracil replace?
Thymine
RNA has a _______-helix structure.
Single
Give the two matching base pairs in DNA:
Adenine and Thymine
Cytosine and guanine
Give the two matching base pairs in RNA:
Adenine and uracil
Cytosine and guanine
Many nucleotides join together to form ______ chains.
Polynucleotide
What is the sugar-phosphate backbone?
The chain of phosphates and sugars.
What joins polynucleotide strands together?
Hydrogen bonds between bases.
How many hydrogen bonds form between adenine and thymine?
Two
How many hydrogen bonds form between cytosine and guanine?
Three
Give 4 differences between the structure of DNA and RNA:
1) RNA has a ribose sugar, DNA has a deoxyribose sugar.
2) RNA has uracil instead of thymine, DNA has thymine.
3) RNA’s nucleotides form a single polynucleotide strand, DNA’s nucleotides from a double polynucleotide strand.
4) RNA strands are much shorter than most DNA polynucleotides.
What is a phosphodiester bond?
A covalent bond between two nucleotides, resulting in a condensation reaction.
