Level 2 Bio: Gene Expression Flashcards
Anticodon
Three consecutive bases on the tRNA
Codon
Three consecutive bases on the mRNA
Deletion mutation
A mutation on the DNA where a base(s) is removed, resulting in a frame shift
DNA
Deoxyribose nucleic acid, A joins with T, C joins with G. Double stranded, helix shaped large molecule, a whole chromosome. Deoxyribose sugar
Enzyme
A folded protein which acts as a biological catalyst to speed up the rate of a chemical reaction in an organism
Frameshift
Change in bases that the ribosome reads
Gene
A piece of DNA which codes for the making of a protein/feature
Gene expression
The process where the instructions on our DNA are converted into a functional protein, includes transcription, translation and protein folding
Genotype
The genetic makeup of an organism for a feature
Insertion mutation
A mutation on the DNA where a base(s) is added resulting in a frame shift
Metabolic pathway
A series of enzyme controlled reactions, where the product of one reaction becomes the substrate of the next
Missense mutation
A change of the base on the DNA which codes for a different amino acid. This may or may not alter the shape of the protein and therefore its function.
mRNA
Messenger RNA. Made during transcription in the nucleus. Carries the instructions of the ribosome to make a polypeptide chain. Contains codons.
Mutagen
Environmental factor which causes the mutation e.g x-rays etc
Mutation
A sudden permanent change in the DNA base sequence
Non-sense mutation
A change of the base on the DNA which changes the instructions so a STOP codon occurs in the wrong place. Protein is greatly affected.
Peptide bond
Bond formed between 2 amino acids during translation
Phenotype
The physical appearance of a feature.
Point mutation
A change of only one or a few bases on the DNA
Protein
A substance made up of many amino acids joined together to form a polypeptide chain, which gets folded into a functional protein (enzymes area type of protein)
Redundancy
The fact that multiple codons code for the same amino acid, eg CCU, CCC, CCA and CCG all code for the amino acid Pro
Same-sense mutation
A change of the base on the DNA where the bases still code for the same amino acid. This is due to the redundancy of the genetic code.
Silent mutation
A mutation that is neither favourable nor harmful, that remains in a population.
Start codon
The start signals on the mRNA which initiates translation. Always AUG.
Stop codon
These 3 codons on the mRNA (UAA, UAG, UGA) do not code for an amino acid therefore telling the ribosome where to stop translation.
Substitution mutation
A mutation where the base(s) on the DNA are swapped
Transcription
The process by which DNA going to mRNA, occurs in the nucleus. Controlled by RNA polymerase
Translation
The process by which mRNA going to polypeptide chain, occurs in the cytoplasm on the ribosome
Triplet
Three consecutive bases on the DNA
tRNA
Transfer RNA. Carries an amino acid to the ribosome. 3 bases on the mRNA= an anticodon
What is gene expression
Gene expression is the process by which information from a gene is used to make a protein.
What does the base sequence of a DNA molecule code for
The base sequence of a DNA molecule codes for the amino acids that make up proteins.
What codes for 1 amino acid
A sequence of 3 bases in DNA (a triplet) codes for 1 amino acid
A sequence of many amino acids joined together with peptide bonds forms a __________
A sequence of many amino acids joined together with peptide bonds forms a POLYPEPTIDE.
One gene codes for one _________ (basic protein, most proteins made of many Polypeptides).
One gene codes for one POLYPEPTIDE (basic protein, most proteins made of many Polypeptide).
What is the primary structure
The primary structure is the simplest type of protein structure. It is the linear chain of amino acids that make up a protein.
The primary shape is bent or twisted into a helix or pleated sheet. The shape is held in place by _________ bonds. The secondary structure is the folded structures that forms within a polypeptide when atoms interact on the “backbone”.
The primary shape is bent or twisted into a helix or pleated sheet. The shape is held in place by HYDROGEN bonds. The secondary structure is the folded structures that forms within a polypeptide when atoms interact on the “backbone”.
In the alpha helix the carbonyl of one amino acid is hydrogen bonded to the amino H of an amino acid 4 down the chain. This bonding pattern pulls the polypeptide chain into a ________ structure resembling a curled ribbon.
In the alpha helix the carbonyl of one amino acid is hydrogen bonded to the amino H of an amino acid 4 down the chain. This bonding pattern pulls the polypeptide chain into a HELICAL structure resembling a curled ribbon.
The tertiary structure is the folding of what?
The tertiary structure is the folding of secondary structures bent into a globular shape & is the 3D structure of the protein.
Quaternary structures are made of 2 or more ____________ chains held loosely together.
Quaternary structures are made of 2 or more POLYPEPTIDE chains held loosely together.
Globular proteins have what kind of a function
Globular proteins have a chemical function
Fibrous protein molecules form long chains or fibres (they have primary, __________, tertiary and __________ structure). Their fibrous nature makes them __________ in water
Fibrous protein molecules form long chains or fibres (they have primary, SECONDARY, tertiary and QUATERNARY structure). Their fibrous nature makes them INSOLUBLE in water
mRNA=??
Messenger RNA
rRNA=??
Ribosomal RNA
tRNA=??
Transfer RNA
DNA codes for_________
Proteins
Where are proteins synthesised
In ribosomes
RNA stands for
Ribonucleic acid
DNA stands for
Deoxyribonucleic acid
Nucleic acids (make up DNA) are ________ composed of monomers (smaller units) called a ________
Nucleic acids (make up DNA) are POLYMERS composed of monomers (smaller units) called a NUCLEOTIDE
What is the monomer of DNA
Nucleotide: sugar, base & phosphate
The bases in DNA are=??
Cytosine with Guanine & Thymine with Adenine