Nucleic Acids and Proteins Flashcards
mRNA - name and function
messenger RNA - carries the genetic code from the nucleus to the ribosome
rRNA name and function
ribosomal RNA - structural component of ribosomesalong with other proteins
tRNA name and function
transfer RNA - brings correct and specific amino acids to the ribosome
An intron is ..
Non-coding component of pre-mRNA
An exon is
Coding part of mRNA
A Codon is ..
Three base sequence on mRNA
An Anticodon is ..
Three base sequence on tRNA
The genome is …
All the genetic information in an individual or cell
A nucleotide is …
Monomers of nucleic acids - contain a phosphate group, pentose sugar and nitrogenous base
Globular proteins are proteins with functional roles closely linked to their 3Dshape. Examples of these are …
e.g. enzymes, antibodies
Fibrous proteins are proteins with structural roles. Examples of these are ..
e.g. keratin, collagen, elastin
Quaternary protein structure is …
Two or more polypeptides joined together
Tertiary protein structure is ..
A 3D structure composed of a folded secondary structure
The secondary structure of a protein is …
The folding of the primary structure into alpha helix, beta pleated sheetor randomly folded
Primary structure of a protein is ..
Sequence of amino acids
Condensation polymerisation is …
Chemical reaction involving the chemical elimination of water during the formation of a polymer
The monomer of a protein is …
an amino acid
A polymer is
A series of monomers joined together
A monomer is …
Single unit from which a polymer is formed
Proteome
The entire set of proteins expressed by an organism at a given time
A gene is a
heredity unit composed of a DNA section. It occupies aspecific location on a chromosome.It determines thecharacteristic of an organism by encoding for theformation of a protein
Three base sequence on mRNA is called a
Codon ..
Three base sequence on tRNA is called a
Anticodon
Adenine pairs with
Thymine
Guanine pairs with
Cytosine
Pyrimidines bases are ..
Cytosine and Thymine (CAT)
Purine bases are …
Adeninde and Guanine (Ag Pure silver)
DNA stands for
Deoxyribonucleic acid
Define degenerate
More than one codon codes for the same amino acid.
Translation definition
Ribosomes read the mRNA code for _____.
tRNA brings the correct and specific amino acid to the ribosome.
tRNA anticodons are complementary and specific to mRNA codons.
Amino acids are joined together by a peptide bond, in a condensation polymerisation reaction, and a ______ polypeptide is formed.
Transcription definition
DNA unwinds, and RNA polymerase attaches to the promoter region for the _____ gene.
DNA template strand is copied into pre-mRNA via complementary base pairing using RNA polymerase. pre mRNA undergoes RNA processing.
Introns are removed, a 5’ methyl cap and 3’ poly-A tail are added to form mRNA.
mRNA for ______leaves the nucleus and goes to a ribosome.
Function of nucleus in the protein production pathway
DNA transcribed into mRNA during transcription.
Function of ribosome in the protein production pathway
Translates the mRNA code into a polypeptide.
Function of rough endoplasmic reticulum in the protein production pathway
Folding and transport of polypeptide into transport vesicles.
Function of transport vesicles in the protein production pathway
Transport proteins from the rough endoplasmic reticulum to the Golgi apparatus.
Function of Golgi body in the protein production pathway
Final modification and packaging of proteins into secretory vesicles.
Function of Secretory vesicles in the protein production pathway
Allow protein to leave the cell via exocytosis.
Outline importance of RNA processing
3’ poly A tail is added. This leads to the code being protected from enzyme degradation and allows the mRNA to leave the nucleus. 5’ methyl cap is added. This leads to the code being protected from enzyme degradation and allows the mRNA to attach to a ribosome. Introns are removed. This leads to exons that can then be re-arranged during alternative splicing to form a many protein products from the same gene.
Gene regulation is …
the cellular control of the amount and timing of appearance of the functional product of a gene.
Regulatory genes…
control another gene, by coding for a transcription factor like a repressor protein.
A structural genes is ….
a gene that codes for protein that becomes part of the structure OR FUNCTION of an organism.
What is the order of operon components for the trp operon?
Regulatory gene (codes for Trp repressor)
Empty
Promoter
Operator
Structural genes EDCBA
When tryptophan is present the trp operon is …..
OFF
When tryptophan is low or absent the trp operon is …
ON
When tryptophan is present the repressor protein is …
Active. It binds to the operator preventing transcription and gene expression.
When tryptophan is low or absent then the repressor protein is …
Inactive. It cannot bind to the operator allowing RNA polymerase to trasncribe the genes and for them to be expressed.
What do the structural genes in the trp operon code for?
Enzymes and enzyme subunits involved in the biosynthesis of tryptophan.
Define the word universal in relation to the DNA code
The DNA code results in the same amino acid being translated in all living things e.g. TAC will code for Met in all living things.
