2.6 - How is CF inherited? Flashcards
What does allele mean?
Different forms of a gene
What does genotype mean?
The alleles present in an individual represented by betters
What does phenotype mean?
The physical characteristics of an individual
What does homozygous mean?
A genotype with two alleles that are the same
What does heterozygous mean?
A genotype with two alleles that are different
What does recessive mean?
Alleles that are only expressed in the phenotype if two are present
What does dominant mean?
Alleles that are always expressed in the phenotype
What is monohybrid inheritance?
When the inheritance of one single allele from two parents is studied.
What are the steps when creating a punnet square ?
1- Give the parents genotypes 2- Give the possible parents gametes 3- Draw and fill in the Punnett square 4-Make a key matching genotypes to phenotypes 5- Give the probability or ratio
How is CF inherited?
1- CF gene occurs in alternative forms or alleles.
2- The normal allele does not contain a mutation and is dominant.
3- The mutated allele is recessive.
4- One out of twenty five people are cystic fibrosis carriers.
5- Carriers can pass on an C or c in their gametes as they are heterozygous.
What does codominace mean?
when both alleles are expressed
what are Homologous chromosomes?
Homologous chromosomes are chromosomes that can pair as they contain sequences for the same genes.
What does locus mean?
Locus means the position of a gene on a chromosome.
What did Darwin believe happened when parents characteristics were inherited in sexual reproduction?
The characteristics are blended e.g. red and white would lead to pink flowers.
What type of plant did Mendel use to work out how inheritance works?
Peas
What did Mendel look after at the monastery?
The garden
How long did Mendel’s study take? What did he keep?
10 years and a detailed record
What pattern did Mendel notice?
If you breed red and white flower peas, the first generation will all have red flowers. The second generation will have red and white flowers.
What fundamental law of inheritance did Mendel discover?
That each parent passes on a ‘factor’.
Why were his findings not widely recognised until much later?
Only published in a small journal, language barrier, not a professional scientist, stopped his research and his notes were burnt.
What do we call Mendel’s factors today?
Genes
What were mendels conclusions?
There are inherited factors (genes), from parents, that control different characteristics.
-Some factors are stronger and show up more often, they are dominant.
