Point Mutations
What type of mutation occurs when one nitrogenous base is replaced by another?
What is a substitution (point mutation)?
What happens to the reading frame when a base is inserted or deleted?
What is the reading frame shifts, changing all codons after the mutation?
Which chromosome mutation results in a section being lost?
What is a deletion?
Which chromosome disorder is caused by Trisomy 21?
What is Down syndrome?
What is the ultimate source of new alleles in a population?
What are mutations?
Which type of point mutation changes one amino acid in the protein?
What is a missense mutation?
Name the two types of frameshift mutations.
What are insertions and deletions?
Which mutation causes part of a chromosome to be copied twice?
What is a duplication?
Turner syndrome results from what chromosome abnormality?
What is monosomy X (missing one X chromosome)?
Name one cause of mutations.
What is DNA replication errors, cell division errors, or mutagens?
Which type of point mutation creates a stop codon?
What is a nonsense mutation?
Why do frameshift mutations usually have a greater effect than point mutations?
What is they alter every codon after the mutation, changing many amino acids?
Which mutation occurs when a chromosome segment reattaches backwards?
What is an inversion?
Which genetic disease is common in sub-Saharan Africa because it provides protection against malaria?
What is sickle-cell anaemia (or sickle-cell trait)?
Different genotypes produce different what?
What are phenotypes?
Which type of point mutation has no effect on the amino acid sequence?
What is a silent mutation?
During which cellular process are frameshift mutations most likely introduced?
What is DNA replication?
Which mutation occurs when part of one chromosome attaches to another chromosome?
What is a translocation?
Which genetic disease is more common in Mediterranean populations and also provides malaria resistance in heterozygotes?
What is thalassaemia?
Natural selection acts directly on an organism's genotype or phenotype?
What is the phenotype?
Albinism is caused by what type of mutation, and what protein is affected?
What is a nonsense point mutation that prevents production of melanin?
Explain why adding one nucleotide changes the entire protein sequence.
What is because codons are read in groups of three, so one insertion changes every codon after it?
What error during meiosis can lead to trisomy or monosomy?
What is non-disjunction?
Why is the sickle-cell allele maintained in some populations despite causing disease?
What is heterozygous individuals have increased resistance to malaria, increasing survival and reproduction?
Explain how a favourable mutation can become more common in a population.
What is individuals with the favourable phenotype survive and reproduce more successfully, increasing the frequency of that allele over generations?