Exam 23: Patterns of Gene Inheritance

In cattle,consider that the lack of horns is dominant to the presence of horns.A bull without horns is crossed with a horned cow.Of four offspring,one is horned and the other three lack horns.The bull is

The _____ indicates the gene combination of an individual.

In horses,black coat (B)is dominant over brown coat (b),and being a trotter (T)is dominant over being a pacer (t).A black horse who is a pacer is crossed with a brown horse who is a trotter.The offspring is a brown pacer.What is the genotype of the brown trotter parent?

Which genetic disorder is associated with an irregular shape of the red blood cells?

To try and discover if the environment has an effect on a particular characteristic,scientists often examine

All but one of the following experiments would allow a scientist to discover if the phenotype of an organism would be affected by environmental changes.Choose the experiment that would NOT show environmental effects.

The ability to roll the edges of the tongue upward in a U-shape has been considered to be an inherited ability.The standard assumption is that tongue-rolling is a dominant allele at a single gene locus.Which of the following would cast doubt on this assumption?

If the genotype of an organism is YySsTt,then yST would represent

Indicate the genotypic and phenotypic ratios that you could expect if an individual who is heterozygous for Huntington disease has children with a normal individual.

Which of the following would be considered a heterozygous dihybrid genotype?

Alternative forms of a gene that influence the same trait and are found at the same location in homologous chromosomes are called

A cross is made between two parents with genotypes AaBB and aabb.If there are 32 offspring,how many of them would be expected to exhibit both dominant characteristics?

When crossing individuals with differing genotypes,in which kind of cross would you expect to have your actual results match the predicted results 100% of the time the cross is made?

Unattached earlobes (EE or Ee)are dominant over attached earlobes (ee).A couple both have unattached earlobes.Both notice that one of their parents on both sides have attached earlobes (ee).Therefore,they correctly assume that they are carriers for attached earlobes (Ee).If the couple proceeds to have four children,then

What are alleles?

If an organism shows a recessive phenotype,such as short pea plants,its genotype can be

If an albino (recessive)woman is married to a man with normal coloring and they have an albino child,what was the genotype of the man?

You have two true-breeding rose bushes,one with red flowers and one with white flowers.A cross between these two roses yields a bush with pink flowers.What condition does this demonstrate?

Which of the following crosses will yield only homozygous recessive offspring?

Tay-Sachs is a recessive genetic disease in humans.If one parent is homozygous normal and the other is a carrier (heterozygous),what are the chances that their child will have this disease?