Definitions

Question 1

Anticodon

Answer 1

An anticodon is 3 bases on tRNA molecule that are complementary to the mRNA codon.

Question 2

Codon

Answer 2

A codon is 3 consecutive bases on the mRNA strand that codes for an amino acid.

Question 3

Deletion Mutation

Answer 3

A deletion mutation is a mutation on the DNA where a base(s) is deleted from the DNA sequence resulting in a frameshift.

Question 4

DNA

Answer 4

DNA is a large molecule which is a double-stranded helix shape, where A joins with T and C joins with G.

Question 5

Enzyme

Answer 5

An enzyme is a folded protein that acts as a biological catalyst to speed up the rate of a chemical in an organism/cell.

Question 6

Frameshift mutation

Answer 6

After a mutation, all the triplets are incorrect as they are not ‘read’ in their correct threes.

Question 7

Gene

Answer 7

A gene is a piece of DNA that codes for a particular trait or characteristic.

Question 8

Gene expression

Answer 8

Gene expression is the process where the instructions on our DNA are converted into a functional protein, this includes transcription, translation, and protein folding.

Question 9

Genotype

Answer 9

A genotype is the genetic makeup of an organism for a feature

Question 10

Insertion mutation

Answer 10

where a base is inserted into the DNA sequence resulting in a frameshift

Question 11

Metabolic pathway

Answer 11

A metabolic pathway is a series of enzyme-controlled reactions, where the product of one reaction becomes the substrate of the next.

Question 12

Missense mutation

Answer 12

Missense mutations are changes 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

Question 13

mRNA

Answer 13

mRNA is the messenger RNA, which is made during transcription in the nucleus. This carries the instructions to the ribosome to make a polypeptide chain. contains codons.

Question 14

Mutagen

Answer 14

An Environmental factor like radiation or chemical substance that causes the mutation.

Question 15

Mutation

Answer 15

A mutation is a permanent change in the bases of the DNA, they are the ultimate source of variation because they can create new alleles.

Question 16

Non-sense mutation

Answer 16

A non-sense mutation is 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

Question 17

Peptide Bond

Answer 17

The bond joining amino acids to each other in a polypeptide chain during translation

Question 18

Phenotype

Answer 18

The phenotype is the physical appearance of a feature

Question 19

Point mutation

Answer 19

A point mutation is a change of only one or a few bases in the DNA

Question 20

Protein

Answer 20

A molecule containing long strings of amino acids joined together by peptide bonds

Question 21

Redundancy

Answer 21

The fact that multiple codons code for the same amino acid - eg : CCU, CCC, CCA, and CCG all code for the amino acid Pro

Question 21

RNA

Answer 21

RNA is short and single-stranded, where U bonds with A, and G bonds with C. There are 3 types of RNA tRNA, mRNA, and rRNA

Question 22

Silent Mutation

Answer 22

A silent mutation is a mutation that is neither favourable nor harmful, that remains in a population

Question 23

Start codon

Answer 23

A start codon is the start signal on the mRNA which initiates translation. This is always AUG

Question 24

Stop codon

Answer 24

These 3 codons on the mRNA (UAA, UAG,UGA) do not code for an amino acid therefore telling the ribosome where to stop translation

Question 25

Substitution mutation

Answer 25

A substitution mutation is a mutation where the base(s) on the DNA are swapped

Question 26

Transcription

Answer 26

making an mRNA copy of DNA with the help of enzymes including RNA polymerase

Question 27

Translation

Answer 27

mRNA is read by ribosome to produce a particular sequence of amino acids

Question 28

Triplet

Answer 28

A triplet is 3 consecutive bases on the DNA that code for an amino acid

Question 29

tRNA

Answer 29

tRNA is the transfer RNA. this carries an amino acid to the ribosome, 3 bases on the mRNA = an anticodon

Question 30

Allele

Answer 30

Alleles are alternative forms of genes

Question 31

Alpha Helix

Answer 31

A secondary structure in proteins where there is coiling of the polypeptide chain

Question 32

Amino Acid

Answer 32

Amino Acids are organic molecules that are the building blocks of proteins

Question 33

Beta pleated sheets

Answer 33

common in the secondary structure of proteins that is a twisted, pleated sheet of several stands.

Question 34

Chromatid

Answer 34

A chromatid is one-half of a replicated chromosome.

Question 35

Chromatin fibre

Answer 35

when DNA is being read for protein synthesis it exists as chromatin fiber not tightly wound in chromosomes

Question 36

Coding strand

Answer 36

The coding strand is the strand of DNA that is not used for transcription and is identical in sequence to mRNA, apart from the mRNA having U, not T.

Question 37

Deoxyribose

Answer 37

the sugar component in the side chains of DNA

Question 38

Double Helix

Answer 38

The twisted ladder shape of DNA with a phosphate sugar backbone.

Question 39

Nucleotide

Answer 39

The subunit of DNA, made of a sugar-phosphate and a nitrogenous base

Question 40

Polypeptide chain

Answer 40

A long chain of amino acids joined by peptide bonds

Question 41

Purine

Answer 41

Double ring structure bases G & A

Question 42

Pyrimidine

Answer 42

Single ring structure bases C, U, & T

Question 43

Ribose

Answer 43

The suagr component in the single stands of RNA

Question 44

Ribosome

Answer 44

The site of protein synthesis. Made of rRNA

Question 45

Missense mutation

Answer 45

Different amino acid

Question 46

same sense mutation

Answer 46

same amino acid

Question 47

nonsense mutation

Answer 47

stop codon

Question 48

substrate

Answer 48

Molecule/substance that binds with an enzyme in a chemical reaction

Question 49

template strand

Answer 49

The strand of DNA that the RNA polymerase uses as a guide to build complementary mRNA

Question 50

Uracil

Answer 50

A base found in RNA instead of thymine pairs with adenine

Question 51

Enzymes are a type of

Answer 51

protein