Selective Breeding
What is selective breeding?
The process in which humans deliberately choose certain plants or animals based on their traits.
What do we call a trait that is passed down from parents to offspring?
An Inherited Trait.
What is the purpose of a punnett square?
To calculate the predicted percentage of an offspring between two different parent types.
What is a gene?
A segment of DNA.
Which trait is expressed when both a dominant and recessive allele are present?
A heterozygous trait.
Why do farmers selectively choose plants or animals?
To enhance desirable traits and to increase agriculture productivity and quality.
Name one physical trait that can be inherited from your parents?
Your hair type.
If both parents are heterozygous, what are the possible genotypes of their offspring?
Heterozygous, Homozygous Dominant, and Homozygous Recessive.
Phenotype.
Uppercase.
Name one trait that might be selected for in dogs through selective breeding?
Shorter muzzle (brachycephaly).
Which inherited trait affects whether your hair is curly or straight?
TCHH (Trichohyalin) gene.
In a Bb x bb cross what percentage of the offspring will show the dominant trait?
50%
What is the difference between a genotype and a phenotype?
A genotype describes the genetic information while phenotype is the physical information.
Can a reccesive trait appear if a dominant allele is present? Explain why or why not.
Explain one benefit and one risk of selective breeding.
Benefit: Enhancement of desirable traits. Risk: Reduction of genetic diversity.
Why can siblings have different inherited genes, even though they have the same parents?
The law of independent assortment.
A TT plant and a Tt plant cross, what is the probability of producing a homozygous dominant offspring?
50%
What does the term heterozygous mean?
One dominant trait and one recessive trait.
If two parents show a dominant phenotype, is it possible for their child to show a recessive trait? Explain.
Yes, it is possible for two parents with a dominant phenotype to have a child with a recessive trait.
How can selective breeding lead to genetic disorders over time?
Narrowing the gene pull through inbreeding and intense selection through specific traits which will increase the chance in inheriting harmful traits.
How do inherited traits differ from learned or environmental traits?
Inherited traits come from parents to offspring, while learned or environmental traits are picked up later in life while doing everyday activities.
Two heterozygous produce offspring, what is the phenotype ratio?
3:1
Explain how alleles, genotype, and phenotype are related.
Alleles are different versions of a gene, genotype the specific combination of inherited alleles, and phenotype is the observable physical trait produced by that genotype.
Why can recessive traits seem to skip generations in a family?