Nucleic Acid (Module): Part II Flashcards
The period preceding replication is called the _______.
G1 phase (Gap1)
DNA replication occurs during the ______.
S (synthesis) phase
Following DNA synthesis, there is another period (_______) before mitosis (M).
G2 phase, or Gap2
Cells that have stopped dividing, such as mature neurons, are said to have gone out of the cell cycle into the ______
G0 phase
Cells can leave the G0 phase and reenter the early _____ to resume division.
G1 phase
It is a disease characterized by rapid uncontrolled cell division
Cancer
are a class of anticancer drugs that interfere with DNA replication because their structures are similar to molecules required for normal DNA replication.
Antimetabolites
It is a structural analog of folic acid (folate). A derivative of folic acid is needed in one of the early steps of nucleotide synthesis.
Methotrexate
It inhibits the conversion of folic acid to this needed derivative, which shuts down DNA synthesis
Methotrexate
The genetic master plan of an organism is contained in the sequence of deoxyribonucleotides in its deoxyribonucleic acid (DNA)
PROTEIN SYNTHESIS
TYPES OF RNA:
formed directly by DNA transcription. Post-transcription processing converts the heterogeneous nuclear RNA to messenger RNA
Heterogenous nuclear RNA (hnRNA)
TYPES OF RNA:
facilitates the conversion of heterogeneous nuclear RNA to messenger RNA. It contains from 100 to 200 nucleotides.
Small nuclear RNA (snRNA)
TYPES OF RNA:
carries instructions for protein synthesis (genetic information) to the sites for protein synthesis.
Messenger RNA (mRNA)
TYPES OF RNA:
combines with specific proteins to form ribosomes, the physical sites for protein synthesis. Most abundant type of RNA in a cell (75% to 80% by mass).
Ribosomal RNA (rRNA)
TYPES OF RNA:
delivers amino acids to the sites for protein synthesis. Are the smallest of the RNAs, possessing only 75–90 nucleotide units.
Transfer RNA (tRNA)
is the process by which DNA directs the synthesis of hnRNA/mRNA molecules that carry the coded information needed for protein synthesis
Transcription
A short segment of a DNA strand so transcribed, which contains instructions for the formation of a particular hnRNA/mRNA, is called a ________
gene
It is a segment of a DNA strand that contains the base sequence for the production of a specific hnRNA/mRNA molecule.
gene
It is all of the genetic material (the total DNA) contained in the chromosomes of an organism.
genome
The strand of DNA used for hnRNA/mRNA synthesis
TEMPLATE STRAND
The other DNA strand, although not involved in RNA synthesis, gives the base sequence present in the hnRNA strand being synthesized (with the exception of U replacing T).
INFORMATIONAL STRAND
is a gene segment that conveys (codes for) genetic information
EXON
is a gene segment that does NOT conveys (codes for) genetic information
INTRON
is the process of removing introns from an hnRNA molecule and joining the remaining exons together to form an mRNA molecule
SPLICING
is the process of removing introns from an hnRNA molecule and joining the remaining exons together to form an mRNA molecule.
snRNPs (Small nuclear ribonucleoprotein particle )
“snurps”
is a large assembly of snRNA molecules and proteins involved in the conversion of hnRNA molecules to mRNA molecules
SPLICEOSOMES
is a process by which several different proteins that are variations of a basic structural motif can be produced from a single gene
ALTERNATIVE SPLICING
is all of the mRNA molecules that can be generated from the genetic material in a genome.
TRANSCRIPTOME
is the assignment of the 64 mRNA codons to specific amino acids (or stop signals)
genetic code
is a three-nucleotide sequence in an mRNA molecule that codes for a specific amino acid
codon
is the process by which mRNA codons are deciphered and a particular protein molecule is synthesized. The substances needed for this phase of protein synthesis are mRNA molecules, tRNA molecules, amino acids, ribosomes, and a number of different enzymes
Translation
is an rRNA–protein complex that serves as the site for the translation phase of protein synthesis.
ribosome
What are the five general steps to the translation process:
(1) activation of tRNA
(2) initiation
(3) elongation
(4) termination and
(5) post-translational processing.
part of translation where the ribosome moves down an mRNA molecule three base position (codon) so that a new occupy the ribosomal subunit.
Translocation
What Translation process is this:
An amino acid interacts with ATP to become highly energized. It then form a covalent bond with the 3’ end of a tRNA molecule. Amino acid-tRNA pairing is governed by enzymes
Step 1: Activation of tRNA
What Translation process is this:
The mRNA attached to a ribosome so that the first codon (AUG) is at the P site. A tRNA carrying methionine attached to the first codon.
Step 2: Initiation
What Translation process is this:
Another tRNA with the second amino acid binds at the A site. The methionine transfers from the P site to the A site. The ribosome shifts to the next codon, making its A site available for the tRNA carrying the third amino acid.
Step 3: Elongation