Chapter 13Meiosis and Sexual Life Cycles

How are the traits of parents (such as hair color) transmitted to their offspring?

Concept Check Questions Offspring acquire genes from parents by

inheriting chromosomes

How are the traits of parents (such as hair color) transmitted to their offspring?

Concept Check Questions Offspring acquire genes from parents by

inheriting chromosomes

In the absence of mutation, asexually reproducing organisms produce offspring that are genetically identical to each other and to their parents. Explain.

Concept Check Questions Offspring acquire genes from parents by

inheriting chromosomes

In the absence of mutation, asexually reproducing organisms produce offspring that are genetically identical to each other and to their parents. Explain.

Concept Check Questions Offspring acquire genes from parents by

inheriting chromosomes

In organisms that reproduced sexually, how similar are the offspring to their parents? Explain.

Concept Check Questions Offspring acquire genes from parents by

inheriting chromosomes

In organisms that reproduced sexually, how similar are the offspring to their parents? Explain.

50%

Concept Check Questions Offspring acquire genes from parents by

inheriting chromosomes

In organisms that reproduced sexually, how similar are the offspring to their parents? Explain.

50%

Concept Check Questions Offspring acquire genes from parents by

inheriting chromosomes

In organisms that reproduced sexually, how similar are the offspring to their parents? Explain.

50%

Concept Check Questions Offspring acquire genes from parents by

inheriting chromosomes

How does the karyotype of a human female differ from that of a human male?

Concept Check Questions Fertilization and meiosis alternate in

sexual life cycles

Concept Check Questions Fertilization and meiosis alternate in

sexual life cycles

How does the karyotype of a human female differ from that of a human male?

How does the alternation of meiosis and fertilization in the life cycles of sexually reproducing organisms maintain the normal chromosome count for each species?

Concept Check Questions Fertilization and meiosis alternate in

sexual life cycles

diploid diploid

Concept Check Questions Fertilization and meiosis alternate in

sexual life cycles

diploid meiosis haploid haploid meiosisdiploid

Concept Check Questions Fertilization and meiosis alternate in

sexual life cycles

diploid meiosis haploid fertilization diploid haploid meiosisdiploid

Concept Check Questions Fertilization and meiosis alternate in

sexual life cycles

Dog sperm contain 39 chromosomes. What are the haploid number and diploid number for dogs?

Concept Check Questions Fertilization and meiosis alternate in

sexual life cycles

Dog sperm contain 39 chromosomes. What are the haploid number and diploid number for dogs?

n=39 2n=78

Concept Check Questions Fertilization and meiosis alternate in

sexual life cycles

What process (meiosis or mitosis) is more directly involved in the production of gametes in animals? In plants & most fungi?

Concept Check Questions Fertilization and meiosis alternate in

sexual life cycles

What process (meiosis or mitosis) is more directly involved in the production of gametes in animals? In plants & most fungi?

meiosis mitosis

Concept Check Questions Fertilization and meiosis alternate in

sexual life cycles

Using the concept of chromosome sets, explain briefly how mitosis conserves chromosome number, whereas meiosis reduces the number of chromosomes by half.

Concept Check Questions Meiosis reduces the number of chromosome

sets from diploid to haploid

2 sets

Concept Check Questions Meiosis reduces the number of chromosome

sets from diploid to haploid

4 sets 2

sets

2 sets

mitosis

2 sets

Concept Check Questions Meiosis reduces the number of chromosome

sets from diploid to haploid

4 sets 2

sets

2 sets

meiosis

1 set

1 set

1 set

1 set

How are the chromosomes in a cell at metaphase of mitosis similar to and different from the chromosomes in a cell at metaphase of meiosis II?

Concept Check Questions Meiosis reduces the number of chromosome

sets from diploid to haploid

How are the chromosomes in a cell at metaphase of mitosis similar to and different from the chromosomes in a cell at metaphase of meiosis II?

Twice as many, otherwise identical

Concept Check Questions Meiosis reduces the number of chromosome

sets from diploid to haploid

Fruit flies have a diploid number of 8, and honeybees have a diploid number of 32. Assuming no crossing over, is the genetic variation among offspring from the same two parents likely to be greater in fruit flies or in honeybees? Explain.

Concept Check Questions

Genetic variation produced in sexual life cycles contributes to evolution

Fruit flies have a diploid number of 8, and honeybees have a diploid number of 32. Assuming no crossing over, is the genetic variation among offspring from the same two parents likely to be greater in fruit flies or in honeybees? Explain.

232 > 28

Concept Check Questions

Genetic variation produced in sexual life cycles contributes to evolution

Under what circumstances would crossing over during meiosis not contribute to genetic variation among daughter cells?

Concept Check Questions

Genetic variation produced in sexual life cycles contributes to evolution

Under what circumstances would crossing over during meiosis not contribute to genetic variation among daughter cells?

Parent is homozygous for every gene.

.

Concept Check Questions

Genetic variation produced in sexual life cycles contributes to evolution