Deoxyribonucleic Acid Flashcards
What are the three components of nucleotides
- Phosphate group (PO3-)
- Deoxyribose (5 carbom sugar)
- Nitrogenous base, (A T C G)
Explain the structure of DNA
- its a double helix structure
2.Its anti parallel - Its a complimentary strand( held together by complimentary bases.
what’s the functional unit of DNA
1.Gene, a specific sequence of DNA codes for proteins.
2. Most DNA organism’s genome.
3.
What’s the function of non-coding regions in DNA
Regulate the activity of the genes.
How are DNA in procaryotic cells kept
1.Circular, double stranded
2. Tightly packed. Coiling, compacting, supercoiling.
What is supercoiling
Formation of additional coils due to twisting forces
Who controls the supercoiling
Topoisomerase I and II
What are plasmids
Small circular, linear DNA with non essential genes.
What is the function of Regulatory sequences
They determine when certain genes and associated cell functions are activated.
What are histones and nucleosomes.
- Family of proteins associated with DNA
- Condensed structure formed when double strand DNA wraps around octomer of histones
What is DNA Replication
The process of copying one DNA molecule into two identical molecules.
Explain the DNA production in a semi conservative way.
Two parental DNA are separated since they have weak H bonds.
Two double helix are produced. One parental and one new strand
Name all the components for DNA replication.
Parent DNA
Enzymes
Deoxynucleotide triphosphate (ATCG)
Explain the initiation process in DNA replication
Unwinding starts at the origin of replication
Initiator proteins binds to the DNA
Helicase enzymes cleave the H bond of complementary base pairs
Single Strand binding protein help stabilize the unwound strands
A replication bubble forms with Y shaped fork at the end
Explain the
