(P) Lesson 1: Molecular Basis of Genetics Flashcards
workbook-based
then study of how traits are inherited from one generation to another, how genes are organized and expressed, and how genes behave in populations and evolve over time
genetics
T or F. Genetics plays a central role in all modern EARTH SCIENCES and is essential for an understanding of the living world.
F (biology)
scientific discipline focused on investigating the fundamental principles of inheritance and diversity.
Genetics
T or F. RNA is a macromolecule that contains the genes which encode the amino acid sequences of proteins.
F (DNA)
units of heredity
Genes
T or F. DNA does direct protein synthesis
F (not - they only code for the sequence of amino acids in proteins)
genetic information in the DNA is decoded in the form of
MRNA
which is translated to amino acid sequence of a protein?
MRNA
Try to explain the central dogma of molecular biology
Main point: DNA to mRNA to protein or DNA replication, transcription and Translation
T or F. the flow of information may start from RNA to DNA, the RNA can also be replicated.
T
This stage shows the genetic information in the DNA is copied into mRNA. The sequence of the mRNA bases is the same as that of the DNA.
Transcription
What do you call when the genetic code in the mRNA directs the sequence of amino acids in the protein?
It’s a phase
Translation
Composition of DNA
1.) 5-Carbon sugar (2’-deoxyribose or ribose)
2.) Nitrogenous base (Purines and Pyrimidines)
3.) Phosphate group
T or F. 2’-deoxyribose is a a 5-carbon sugar that forms a ring.
T
What bond does the phosphate group form with C5?
phosphoester bond
What bond does the nitrogenous base form with C1?
N-glycosidic bond
T or F. This N-glycosidic linkage with the sugar involves either the N-1 of the purine or the N-9 of the pyrimidine.
F (opposite)
contain nitrogen within the rings
heterocyclic bases or nitrogenous bases
two types of nitrogenous bases
purines and pyrimidines
this nitrogenous base consist two fused rings
Purine
this nitrogenous base consist 6-sided single ring.
Pyrimidines
enumerate pyrimidine bases
T, U and C
enumerate purine bases
A and G
T or F. nucleoside is composed of three components: a phosphate, a sugar and a base.
F (nucleotides)
T or F. It is possible for nucleotides to combine with additional phosphate units to make diphosphates and triphosphates.
T
relatively short single-stranded nucleic acid chain
oligonucleotide
single-stranded polymer of several nucleotide units.
polynucleotide
catalyze the unwinding of the two strands
helicases
bind to the DNA stabilize the single-
stranded form. A single-stranded DNA is very susceptible to destruction by
nucleases.
SSBP
relaxes the supercoil that forms ahead of the replication fork and aids
with the unwinding process.
DNA gyrase
catalyzes the synthesis of RNA primers, which are required for initiation of DNA synthesis. These provide the required free 3’ hydroxyl group where a nucleotide is added.
Primase
the principal polymerase in the DNA replication in bacteria. It catalyzes the incorporation of new nucleotides to the elongating DNA.
DNA polymerase III
removes the RNA primer. It fills the gaps formed in the growing molecule that result from the removal of the RNA primer. It also proof-reads and corrects any error in base pairing.
DNA Pol 1
forms a phosphodiester bond between 3’-OH and 5’-PO4 groups between the DNA fragments. This forms a continuous DNA molecule.
DNA ligase
The 5’–3’ strand that proceeds to the direction of the replication fork is called?
leading strand
More RNA primers are added by the primase as the DNA helix is unwound, and is elongated by Pol III. The short DNA fragments added to the primase are called the?
Okazaki fragments
made up of unbranched chain of nucleotides as in DNA
RNA
T or F. RNA differs from DNA in that the sugar unit is B-D-ribose, uracil pairs with adenine instead of thymine and is in general, double-stranded.
F (single stranded)
process of copying of a DNA template in the form of RNA
Transcription
T or F. All RNAs are synthesized using a DNA template.
T
This enzyme acts like DNA polymerase, requiring a template, nucleotide triphosphates (ATP, CTP, GTP, and UTP), and magnesium ion.
RNA Polymerase (transcription)
T or F. The RNA polymerase is able to initiate RNA synthesis without a primer, unlike DNA polymerase.
T
a core enzyme and a sigma (σ) subunit are referred to as?
holoenzyme
What subunit is involved in initiating transcription at the beginning of a gene?
σ subunit
p’wede rin naman -10 and -35 kasi σ subunit lang rin nakakarecognize nto
Where specific DNA do subunits bind? Transcription
promoter
defines the beginning of a gene for transcription
promoter site
The transcription start site (+1) has two groups before the first base of the DNA that will be transcribed into the first base of RNA.
Transcription
-35 and -10
T or F. The bases to the left (negative numbers) of the transcription start site are said to be DOWNSTREAM, and the bases to the right (positive numbers) are said to be UPSTREAM
F (opposite)
template used for RNA synthesis is the
anti-sense strand
strand that codes for the sequence of the gene is called the
sense or coding strand
What phase is this?
The start of RNA synthesis occurs at the +1 position, utilizing nucleotide triphosphates (NTPs). The sigma subunit is no longer required at once the helix is opened and is released from the core polymerase shortly after this phase of synthesis.
under Transcription
Initiation