1.1 Structure of DNA Flashcards
Name the 3 components of a nucleotide
- deoxyribose sugar
- phosphate
- base
Where is the 3’ end of the nucleotide?
the bottom left of the deoxyribose sugar
Where is the 5’ end of the nucleotide?
the phosphate
What are poly nucleotides?
nucleotides in a chain joined together by sugar-phosphate bonds to make long chains of nucleotides
What makes up the backbone of DNA?
the sugar and the phosphate
What are the 4 different bases?
- Adenine
- Thymine
- Cytosine
- Guanine
What does complementary base pairings mean?
that the bases shapes match up
What are the base pairing rules?
adenine->thymine
cytosine->guanine
What type of bond joins the deoxyribose sugar of one nucleotide to the phosphate of another nucleotide?
sugar-phosphate bond
What type of bond joins bases together?
hydrogen bonds
What is the structure of the double helix described as?
having two anti-parallel chains of nucleotides because one side goes from 5’ to 3’ and the other side goes from 3’ to 5’
What is a prokaryote?
- an organism lacking a nucleus.
- They usually have a single circular double stranded chromosome.
- Some prokaryotes have a second chromosome which can carry extra non-essential genes-this is called a plasmid.
What is a eukaryote?
- organisms with a nucleus containing several linear chromosomes which are tightly coiled and packaged with histone proteins
- they also have extra DNA out with the nucleus-circular chromosomes in their mitochondria and chloroplasts(mitochondrial and chloroplast DNA)
Describe mitochondrial DNA
- it is circular and found in the mitochondria of both plants and animals
- It is inherited solely from the mother along with the other cell organelles
Describe chloroplast DNA
- it is circular and found only in plants
- it is inherited solely from the mother along with the other cell organelles during cell division
