Plant and animal breeding Flashcards
What is meant by discrete variation?
Fits into distinct categories
What type of inheritance causes discrete variation?
Single gene inheritance
What is meant by continuous variation?
Wide range of characteristics
What type of inheritance causes continuous variation?
Polygenic inheritance
What is a test cross?
Used to identify organisms with unknown genotypes
How is a test cross conducted?
Cross unknown with homozygous recessive
What is meant by inbreeding?
Crossing related individuals
What is meant by outbreeding?
Crossing unrelated individuals
Why is inbreeding useful?
Ensures offspring receive alleles for desired characteristics
Why can inbreeding be harmful?
It can lead to inbreeding depression
What is meant by inbreeding depression?
A build up of homozygous recessive deleterious alleles
Why is inbreeding depression less likely to occur in plants?
Years of natural selection eliminates deleterious alleles
What is meant by an F1 hybrid?
Produced by cross between two genetically dissimilar parents who have desired traits
Why can the F1 hybrid be useful?
Show hybrid vigour – increased yield, fertility or other beneficial characteristics
