2.1 Structure of RNA and DNA Flashcards
Describe the basic function of DNA
Holds genetic information which codes for polypeptides (proteins)
Why is it essential that cells contain DNA
So that the genetic information can be passed on to new cells without being damaged
What is the monomer that makes up DNA
A nucleotide
What is DNA made up of (chemically)
Deoxyribose (Pentose sugar)
A nitrogenous base
A phosphate group
What are the 4 nitrogenous bases in DNA
Guanine
Cytosine
Adenine
Thymine
What is the polymer form of a nucelotide (this is worded bad shut up ik)
Polynucelotide
How is DNA created (4)
- It is created via condensation reactions that release water molecules
- Between the Deoxyribose and the Phosphate group
- Creating a Phosphodiester bond (type of covalent bond)
- Phosphodiester bond ensures that the genetic code is not broken down
How is the polynucelotide held together
Strong covalent bonds called phosphodiester bonds
How are the DNA polymer pairs joined together
Hydrogen bonds between the Nitrogenous bases
This is how the double helix strcutre is created as the two chains twist
Name the only condition that through which hydrogen bonds form in polynucelotides
H bonds can only form between complimentary base pairs
Cytosine—Guanine
Adenosine–Thymine
Guanine—Cytosine
Thymine–Adenine
Number of ‘-‘ represent the number of h bond bwteen the bases
Why is the complimentary base pairing important
It helps maintain the order of gentic code when DNA replicates
How does the structure of DNA relate to its function (7)
- Double helix(coiled)- Compact
- Double helix with sugar phosphate backbone—>protects hydrogen bonds
- Double stranded molecule- Both can act as templates for semi conservative replication
- Many hydrogen bonds between bases making it a stable molecule
- Long molecule- stores lots of genetic information
- Complimentary base pairing -Allows identical copies to be made
- Hydrogen bonds between bases are weak so strands can be separated for replication
Draw (use ur imagination) a nucelotide
Phosphate group(circular)
Ribose (pentagonal shape)
Nitrogenous base (Rectangle)
Why did many scientists initially doubt that DNA carried the genetic code
DNA was relatively simple- Chemically simple molecules with few components
What is RNA (3)
*A polymer of a nucleotide formed of a:
Ribose
Nitrogenous base
Phosphate group
*Relatively short
*Single Stranded