gentic diversity- mutations, meiosis Flashcards
what is genetic diversity
- the total number of different alleles in a population
- the greater number of alleles that all members of a species possess, the greater genetic diversity
gene mutation
a change to one or more nucleotide bases, or a change in the sequence of the bases within a gene
chromosome mutation
a change in the structure or number of whole chromosomes
in which cells would a mutation have to occur in order to be inherited
gametes/ cells producing gametes
factors that cause mutations
spontaneous
radiation
chemicals biological agents
what do we call something that increases the rate of mutations
mutagenic agent
gene mutation types
deletion and insertion of bases
substitution
which type of mutation causes a frame shift
deletion and insertion
example of a genetic disease caused by substitution mutation
sickle cell anaemia
why might a substitution mutation not cause any change to the amino acid in a polypeptide
the code is degenerate
may result in a trip,et which codes for the amino acid
chromosome mutations
changes in the structure or number of whole chromosomes
polyploidy
where organisms have three or more whole sets of chromosomes
commonly seen in plants
non disjunction
when individual homologous pairs fail to separate during meiosis
resulting gamete either has one more or one fewer chromosome
what does the process of mitosis result in
2 daughter cells
genetically identical
same number of chromosomes
often diploid
what does meiosis result in
4 daughter cells
genetically different
half the number of chromosomes
haploid
gametes