Chapter 6: Nucleic Acids & Protein Synthesis Flashcards
What are the 4 topics under this unit?
- Structure and function of nucleic acids
- DNA replication
- Protein Synthesis
- Mutation
What is a nucleotide composed of?
- Phosphate group
- Pentose sugar
- Nitrogenous base
What are the bonds between neighbouring nucleotides and what is the bond between base pairs?
- Between nucleotides: Phosphodiester bond
- Between base pairs: Hydrogen bond
Name the 5 kinds of nitrogenous bases and identify which base pairs together
- Adenine & Thymine
- Guanine & Cytosine
- Uracil & Adenine
How many rings does a purine have? Which nitrogenous bases are purines?
- 2 rings
- Guanine & Adenine
How many rings does a pyrimidine have? Which nitrogenous bases are pyrimidine?
- 1 ring
- Cytosine, Uracil & Thymine
Differenciate between RNA and DNA
- RNA is usually single-stranded while DNA is usually double-stranded // double-helix structure
- RNA has a ribose sugar while DNA has a deoxyribose sugar
- RNA has URACIL while DNA has THYMINE
What are 3 examples of polynucleotides?
RNA
DNA
ATP
Identify 3 kinds of RNA and state their function
mRNA: transfers replicated genetic information to ribosomes for protein synthesis
rRNA: forms ribosomes, needed for protein synthesis
tRNA: brings amino acids from the cytoplasm to the ribosomes to create proteins
What is ATP composed of?
- 3 phosphate groups
- Adenine molecule
- a Ribose sugar
What is the function of ATP?
Used as the energy “currency” of the cell; provides energy needed for work
State the name for the model on how DNA is replicated and explain what it means.
- Semi-conservative
- Half of each DNA molecule contains 1 strand of the original parent DNA
Identify the 4 enzymes and their purposes in DNA replication
- Helicase - unwinds DNA
- DNA polymerase - adds base pairs to template strands and proofreads its own work
- Primase - adds “RNA primers” on the lagging strand that indicate to the DNA polymerase on where it should work
- Ligase - “glues” or joins together Okazaki fragments to the lagging strand
DNA is replicated in the ____ to _____ direction
So the leading strand is in the ___ to ___ direction
5’ –> 3’ direction
3’ –> 5’ direction
Why is DNA antiparallel?
This arrangement allows for complementary nucleotide bases to pair with one another