2.4: Variation & Inheritance Flashcards
What is variation?
The differences within a population
What causes variation?
Combining genes from two parents
What is a phenotype?
A particular characteristic description
What are phenotypes determined by?
The genes present in an organisms DNA
What are the types of variation?
Discrete & Continuous
What is discrete variation?
A result of single gene inheritance - the characteristics are only dependent on one gene - where the measurements fall into distinct groups
What is continuous variation?
A result of polygenic inheritance - characteristics caused by a number of genes - where there is a range of values between a minimum and a maximum
What chart can show discrete variation?
Bar Chart
What chart can show continuous variation?
Histogram
What are the different versions of a gene called?
Alleles
What are dominant alleles?
An allele that will automatically determine a phenotype
What is a recessive allele?
An allele that can be dominated by another when determining phenotype
What is a genotype?
The combination of alleles
What does homozygous mean?
When both alleles are the same
What does heterozygous mean?
When both alleles are different
