Inheritance and Genetic Variation

What are chromosomes?

• Long strands of DNA that contain lots of genes.

• Different versions of a gene.

• The basic unit of heredity; controls a specific trait.

• A characteristic passed from parent to offspring

• The differences that occur from a mixture of genes

What are alleles?

• Long strands of DNA that contain lots of genes.

• Different versions of a gene.

• The basic unit of heredity; controls a specific trait.

• A characteristic passed from parent to offspring

• The differences that occur from a mixture of genes

The difference between genotype and phenotype is :

• Genotype shows the combination of alleles that provides the genes for a trait, while phenotype is the expression of the trait, what it will look like.

• Phenotype shows the combination of alleles that provides the genes for a trait, while genotype is the expression of the trait, what it will look like.

A complete Punnett square here shows a cross between two mice with different fur color, agouti (A) and black (a). What is the probability of the recessive phenotype being expressed?

• 25%

• 50%

• 75%

• 100%

The offspring of asexually reproducing organisms have genes that are ____________ to that of their parent.

• different

• same

• dominant

• recessive

What is a gene?

• Long strands of DNA that contain lots of genes.

• Different versions of a gene.

• The basic unit of heredity; controls a specific trait.

• A characteristic passed from parent to offspring

• The differences that occur from a mixture of genes

How can you tell if an offspring is the result of asexual or sexual reproduction?

• If the offspring is genetically identical to its parent then it will be the result of asexual reproduction, and if it is genetically different to its parents, then it will be the result of sexual reproduction.

• If the offspring is genetically different to its parent then it will be the result of asexual reproduction, and if it is genetically identical to its parents, then it will be the result of sexual reproduction.

In sexually reproducing organisms, each parent contributes _____________ of the genes acquired by the offspring.

• an eighth

• a quarter

• a half

• three quarters

What is genetic variation?

• Long strands of DNA that contain lots of genes.

• Different versions of a gene.

• The basic unit of heredity; controls a specific trait.

• A characteristic passed from parent to offspring

• The differences that occur from a mixture of genes

How is it genetically possible for parents with both natural brown hair, a dominant phenotype have an offspring with blonde hair, a recessive phenotype?

• Both parents have blonde, but have dyed their hair brown.

• Both parents have the allele for blonde hair that they passed down to their offspring.

• The offspring is not their child.