Famous Scientists
Prior to the discovery of DNA as genetic material, scientists thought it was actually molecule instead.
Protein
The four nitrogenous bases found in DNA (names, not letters)
adenine (A), cytosine (C), guanine (G), and thymine (T)
The name of the enzyme that carries out transcription.
RNA polymerase
Operator
Process by which cells become specialized
Differentiation
This scientist was known for his rule that there was always an equal ratio of A-T and G-C in DNA
Chargaff
In the DNA double helix, the two strands are this orientation.
Antiparallel
The name of the region of DNA that signals the transcriptional start site.
Promoter region
The three genes in the lac operon model.
lacZ, lacY, lacA
This is a type of gene regulation we discussed (hint: model).
lac Operon Model
If an organism’s DNA contains 40% thymine nucleotides, this is the percentage of the DNA that must be cytosine nucleotides.
10%
New bases are added to this end of the growing DNA strand during replication.
3' (in the 5' - 3' direction)
The organelle that carries out the process of translation.
Ribosomes
When lactose is present, transcription _______ occur.
DOES
Fill in the blanks: Cells regulate __________ production by ______ ______________.
Cells regulate enzyme production by gene regulation.
These two scientists determined the double-helix structure of DNA
Watson & Crick
This enzyme is responsible for joining the Okazaki fragments together on the lagging strand.
DNA ligase
The number of nucleotides that make up a codon.
3
When lactose is absent, transcription _______ occur.
DOES NOT
List the TWO reasons why gene regulation is beneficial.
1. Conserves energy (proteins only produced when needed)
2. Ensures genes are expressed in the appropriate cell types and at the correct stage of development
This X-ray crystallographer generated the image that helped Watson & Crick determine the double helix structure of DNA
Rosalind Franklin
This enzyme unwinds the DNA double helix during replication.
DNA helicase
RNA that carries an amino acid to the ribosome and has an anticodon.
(name and __RNA)
Transfer RNA (tRNA)
This binds to the promoter and results in high levels of transcription.
Activator
X chromosomes in females is become randomly inactivated during X chromosome inactivation. This is the term for the inactivated chromosome.
Barr body