mutations

Question 1

what is a mutation

Answer 1

is a permanent change to the sequence of DNA bases, and occurs during cell replication

Question 2

point mutation

Answer 2

a change in nucleotide base at a single point on a gene which changes the mRNA codon sequence and the primary structure of the protein

Question 3

Deletion point mutation

Answer 3

a nucleotide base has been deleted from gene

Question 4

insertion point mutation

Answer 4

a nucelotide base has been inserted

Question 5

substitution

Answer 5

a nucleotide has been substituted for another

Question 6

inversion

Answer 6

inversion of adjacent nuceleotides

Question 7

missense gene mutation

Answer 7

results in a different amino acid being coded for which alters primary structure

Question 8

samesense gene mutation

Answer 8

results in the same amino acid being coded for which does not change primary structure (silent)

Question 9

nonsense gene mutation

Answer 9

results in changing to a stop codon, prevents protein synthesis and results in a non-functioning protein

Question 10

frameshift gene mutation

Answer 10

is the deletion or insertion of nucleotide bases in a DNA sequence where all of the codons are affected, preventing the protein from folding into its structure

Question 11

chromosome mutations

Answer 11

a chromosome mutation is a change in the number or structure of chromosomes in a cell, caused by errors in cell division, affecting the whole chromosome

Question 12

translocation chromosome mutation

Answer 12

genes are exchanged between non-homologous chromosomes (not a pair), occurs furing meiosis

Question 13

duplication chromosome mutation

Answer 13

a gene may be replicated more than once creating extra copies of a gene on a chromosome

Question 14

deletion chromosome mutation

Answer 14

a gene can be removed at any location on a chromosome causing a loss of genetic material

Question 15

inversion chromosome mutation

Answer 15

a section of a chromosome breaks off, inverts and rejoins the chromosome

Question 16

aneuploidy

Answer 16

a chromosome mutation that causes individuals to have an abnormal number of chromosomes

Question 17

spontaneous mutations

Answer 17

the normal rate of mutation in an organism which is caused by spontaneous mutations in DNA replication

Question 18

mutagens

Answer 18

enviromental factos that increase the rate of mutations

Question 19

examples of mutagens

Answer 19

ionising raditon, non-ionizing radiation, mutagenic chemicals, virus

Question 20

somatic mutation

Answer 20

includes all body cells but not germ cells and does not affect offspring, is often localized in one organ or tissue type

Question 21

germinal mutation

Answer 21

occurs in the germ cells in the reproductive organs, mutation is inherited so it can be found in every cell of the offsprings body

Question 22

somatic mutations and cancer

Answer 22

somatic mutations in proto-oncogenes cause cancer tumours