11.2 complex patterns of inheritance

• Biologie
• Middelbare school
• vwo
• Leerjaar 4

Work to be done

Finish this LessonUp:

Class code TV4 LessonUp: agnme

Finish the questions of Biozones 147, 148, 149 and 150

In petunias there are three flower colours. The colour is determined by two alleles: one for white flowers and one for purple flowers. In the phenotypes we can find white and purple, but also pink. A petunia with pink flowers is crossed with a petunia with white flowers. Show the punnett square and the colours you expect in the offspring.

The breeder performs countless crosses with the same two petunias. From this cross he gets 74 pink petunias, 38 white petunias and 37 purple petunias. What is true about the parent plants?

1. one is white, the other purple
2. one is white, the other pink
3. one is purple, the other pink
4. both are pink

In cattle there are three coat phenotypes: white, roan and red. A white cow is crossed with a bull with a red coat. All offspring has a roan coat.

Show the punnett square that explains these phenotypes. 

See previous cross. Two of the roan offspring from the F1 cross are crossed with each other. Give the phenotype ratios you expect from this F2 cross.

Show it with a punnett square. 

- Why do you think sickle cell anemia occurs more often in areas where malaria is endemic?
- A man and a woman are both heterozygous for sickle cell anemia are having a child. What are the chances that the child is protected against malaria? Draw a Punnett square to explain.

Which genotype(s) will lead to blood group B?

A person has blood group A. Of which genotype can this person NOT receive blood in a transfusion?

1. IAIA
2. IAi
3. IAIB
4. ii

Complete on paper and hand in picture:

A person with blood group 0 has a child with a person with blood group AB. What is the chance this child will have blood group A?

Complete on paper and hand in picture:
In a family both grandmothers have blood group 0 and both grandfathers have blood group AB.

Calculate the chance of their grandchild getting blood group B.

Lethal alleles:

In the crested canary the presence of the crest is determined by one gene. The allele for a crest is dominant. In the case of a homozygous dominant canary-embryo this leads to malformations during embryonic development and the death of the embryo. Two heterozygous canaries are crossed. What is the of the first offspring to have no crest?

1. 0%
2. 25%
3. 33%
4. 50%

Lethal alleles:

In the crested canary the presence of the crest is determined by one gene. The allele for a crest is dominant. In the case of a homozygous dominant canary-embryo this leads to malformations during embryonic development and the death of the embryo. Two heterozygous canaries are crossed. What is the chance of the first and second offspring to have no crest?

1. 0%
2. 11%
3. 33%
4. 66%