Gene Expression

Question 1

mRNA:

Answer 1

is a molecule that takes a copy of the genetic information from the DNA and carries it safely to the ribosomes.

Question 2

tRNA:

Answer 2

trna moleules attaches to amino acids in the cell’s cytoplasm. tRNA is responsible for carrying the correct amino acid to a ribosome for protein synthesis.

Question 3

rRNA

Answer 3

helps to make up the ribosomes that are the site of protein synthesis.

Question 4

Polypeptide:

Answer 4

Is formed by peptide bonds that are made up of amino acids

Question 5

Protein

Answer 5

Proteins are large molecules, or polymers, that are made up of many smaller units called amino acids.

Question 6

Triplet:

Answer 6

A series of three bases in DNA. Each triplet codes for a specific amino acid

Question 7

Codon

Answer 7

A set of three bases in mRNA. Each codon codes for a specific amino acid

Question 8

Anticodon

Answer 8

A sequence of three bases on a tRNA molecule. Each anticodon is complementary to a particular mRNA codon.

Question 9

Coding Strand:

Answer 9

The side of the DNA molecule that has exactly the same code as the mRNA (except mRNA has U instead of T).

Question 10

Template Strand

Answer 10

The strand of DNA to which complementary nucleotides are added to make mRNA

Question 11

DNA

Answer 11

DNA is the coding molecule in the nucleus of our cells that holds all of our genetic information. It is made up of a series of phosphate groups, deoxyribose sugars and four nitrogenous bases—A, T, C and G. For cells to create new proteins, they must first make a copy of the DNA.

Question 12

Gene Mutation

Answer 12

A permanent change to the base sequence of a gene

Question 13

Degenerate:

Answer 13

Different codons are able to be coded by the same amino acid.

Question 14

Redundacy

Answer 14

The same amino acid can be coded by different codons and can be advantageous as it can lessen the effect of a gene mutation on an individual, even if there is a new codon/triplet being produced through mutation it will still be coded by the same amino acid as the original triplet, meaning that the protein structure and function would not change.

Question 15

Point Mutation

Answer 15

At one point in the DNA sequence, where there can be an insertion, deletion, or substitution of a base, causing a change to the DNA.

Question 16

Base subsitution

Answer 16

A base substitution is when one base on the DNA is removed and replaced by another. If a base substitution does not result in a change in amino acid, it is called a silent. This is because even though the mutation has caused a change in the DNA sequence, it has had no visible effect on the individual.

Question 17

Missense Mutation

Answer 17

a mutation that causes a change in the sequence of amino acids that are coded and are able to alter the final protein and the original protein it was originally supposed to code for.

Question 18

Nonsense Mutation

Answer 18

a mutation that results in the early production of a stop codon that indicates the end of translation.

Question 19

Base Insertion

Answer 19

Result in adding a new base or sequence of bases to a DNA strand

Question 20

Base Deletion

Answer 20

Result in removing one or more bases from a DNA strand.

Question 21

Reading Frame Shift

Answer 21

A type of gene mutation wherein the addition or deletion of base(s) causes a shift in the reading frame of codons in the mRNA

Question 22

Metabolic Pathway

Answer 22

Metabolic Pathway: is a series of enzyme-controlled reactions in a pathway where the product of one reaction becomes the intermediate substrate of next enzyme controlled reaction, this continues until the final product is formed.

Question 23

Transcription

Answer 23

Transcription job is making a copy of the gene and DNA this will cause the double stranded helix to unwind or unzip the enzyme DNA helicase that will expose to nitrogenous bonds. When this happens, there are two strands that the DNA consists, the template strand and the coding strand, the template strand is the side of the DNA molecule that is copied during protein systhensis,while the coding stranding is the strand of DNA that has the same exact code as mRNA but mRNA has U instead of T. The RNA polymerase will use the template strand to make a single strand mRNA while the coding strand as it has the exact sequence of mRNA its code will be use to make polypeptide.

Therefore the mRNA strand is complementary to the template strand but uracil will be replaced by thymine. Base pairing rule is that Adenine pairs with Thymine and in mRNA Adenine pairs with Uracil) and C pairs with G normally. The RNA polymerase will read the template strand consecutively in three’s known as a triplet that will bring in complementary free nucleotides that will make a single mRNA strand. Once this single gene is transcribed, the RNA polymerase release the DNA which the mRNA strand will travel from the cytoplasm to the nucleus where it will leave to be translated existing via the nuclear pore

Question 24

Translation

Answer 24

Translation is the second stage in protein synthesis and occurs in the cytoplasm. Ribosomes will read the mRNA strand to make a protein.
The ribosome will attach to the mRNA strand (promoting the start of translation)and the ribosome will read a START codon (ie. AUG). A codon is a series of 3 bases on a mRNA strand that each codon Is complementary to a specific amino acid. As each codon is read, the tRNA molecule will bring in its complementary sequence an “anticodon” which is a sequence of 3 bases on a tRNA molecule that each anticodon is complementary to a specific mRNA codon and the starting amino acids (MET) will bond with the mRNA codon and bind to the ribosomes, delivering corresponding amino acids.

Each tRNA molecule has a specific amino acid that attaches to it in the cytoplasm. When amino acids are added together the tRAN molecule moves along allowing the next amino acid to be added, this repeat several times forming a polypeptide chain. This will continue until ribosome reaches a stop codon which will indicate that translation is ending and will cause the polypeptide chain to be released as there are no more amino acids being added into the polypeptide chain causing the ribosome to deattach/disassembles from the mRNA strand and causing the polypeptide chain to fold and bond into a 3d Structure to make a functional protein enzyme.

Question 25

Protein Synthesis

Answer 25

Protein synthesis is the process whereby DNA in the nucleus is used to create a functional protein in the cytoplasm.

Question 26

DNA VS RNA

Answer 26

DNA is a double-stranded molecule that contains genetic information an organelle has. It is found in the Nucleus of cells. DNA consists of nucleotides that made of deoxyribose sugar, phosphate group, one of four nitrogen bases (Adenine,Cytosine, Thymine, Guanine).

RNA is a single stranded molecule that is not confined to the nucleus of cell. RNA nucleotides are made up of ribose sugar, phosphate sugar, four nitrogen bases (Adenine, Cytosine, Uracil, Guanine) RNA molecules have shorted strands of nucleotides and there are three types of RNA - MRNA,TRNA,RNA. It vital as its role is making a protein from the code from DNA

Question 27

RNA structure

Answer 27

A single strand of nucleotides (A, G, U, C). Relatively short and transient molecule

Question 28

Nucleic Acids

Answer 28

The two nucleic acids are DNA and RNA . They are polymers (giant molecules) made up of units called nucleotides.

Question 29

Nucleotides

Answer 29

Nucleotides are made up of a nitrogenous base, a 5-carbon sugar and a phosphate group.

Question 30

Metabolism

Answer 30

sum of all the enzyme-controlled reactions that occur in a cell

Question 31

Gene Expression

Answer 31

the process by which the instructions in our DNA are converted into a functional product (protein).

Question 32

Substrate

Answer 32

the molecule that an enzyme acts on. it has a specific shape that fits the enzyme

Question 33

how mutation works in a gene and how does it effect enzymes

Answer 33

If only gene A is mutated, this means enzyme A is not functional/not made. If enzyme A does not work, it means that the substrate will not be converted to the end product and will accumulate into a toxic protein/product