Regulation of Gene Expression Review Flashcards
chromosome
- organized structure of DNA and found in cells
- singular piece of DNA, containing many genes, regulatory elements, and other nucleotide sequences
- also contain DNA-bound proteins to pack DNA and control its functions
Does the number of chromosomes have an affect on body size or IQ?
No
What is a gene?
Region of chromosomal DNA that can be made into RNA
Where is DNA located?
- Nucleus -> combination of both parents
- Mitochondrial -> Mother only
What happens to sperm mitochondria after fertilization?
It is destroyed
Properties of DNA
- Repeating Deoxyribose of A, T, G, and C
- Phosphate
- Nitrogen Base
DNA Structure
- Double Helix
- Right handed -> curves upward to right
- Sugar Phosphates -> backbone; outside of helix
- Bases (A,T,C,G) -> Face inward; form “steps”
Purines
Adenine and Guanine
Pyrimidines
Cytosine and Thymine
Adenine pairs with ______ in DNA
Thymine
Guanine pairs with ______
Cytosine
Hydrogen bonds between G & C
3 hydrogen bonds
Hydrogen bonds between A & T
2 hydrogen bonds
To which end of a DNA strand are nucleotides added?
3’ end
Therefore synthesis is 5’ -> 3’
What does DNA Polymerase do?
Adds Nucleotides to 3’ end during DNA Replication
The lagging strand in DNA replication is grown 3’ -> 5’, but DNA Polymerase only works in 5’ -> 3’. How is this problem solved?
- Okazaki fragments
- Fragments are then joined by DNA Ligase in the 3’ -> 5’ direction
Exonuclease
- degrades nucleic acid
- works 3’ -> 5’
Mutation types in DNA replication
addition, subtraction, and substitutions
Mutations, changes that occur during DNA replication, may be….
- lethal
- silent
- beneficial
What is transcription?
- process by which DNA is copied into RNA using RNA Polymerase
- Occurs in 5’ -> 3’ Direction
Coding Strand
- Always same strand (3’ -> 5’)
- Used to generate RNA Strand
Non-coding Strand
RNA sequence will be the same as this sequence