cell division

In this hands-on, minds-on activity, students use model chromosomes and answer analysis and discussion questions to learn how a child inherits one copy of each gene from each parent via the processes of meiosis and fertilization.

Students first analyze how the processes of meiosis and fertilization result in the alternation between diploid and haploid cells in the human lifecycle.

Students analyze the results of crossing over and independent assortment to learn how meiosis produces gametes with millions of gametes with millions of different combinations of alleles.

As they model meiosis and fertilization, students follow the alleles of a human gene from the parents' body cells through gametes to zygotes. Thus, students learn how a person inherits one copy of each gene from each of his/her parents.

They learn how the possible outcomes of meiosis and fertilization are summarized in a Punnett square.

A final brief section contrasts sexual reproduction with asexual reproduction.

This activity can be used to introduce meiosis and fertilization or to review these processes. (NGSS)

Download Student Handout: PDF format or Word format

In this hands-on, minds-on activity, students learn how the cell cycle produces genetically identical daughter cells.

They use model chromosomes and answer analysis and discussion questions to learn how DNA replication, mitosis and cytokinesis work together to ensure that each new cell gets a complete set of chromosomes with a complete set of genes. The model chromosomes are labeled with the alleles of several human genes, and students learn how the alleles influence phenotypic characteristics.

To understand how a single cell (the fertilized egg) can develop into the trillions of cells in a human body, students analyze an exponential growth model for the increase in number of cells. The final section provides a brief introduction to cellular differentiation.

This activity can be used as an introduction to the cell cycle and mitosis or to reinforce understanding of these topics.

In our follow-up meiosis and fertilization activity (/sci_edu/waldron/#meiosis) students learn how the movement of gene-carrying chromosomes during meiosis and fertilization results in the inheritance of genes. (NGSS)

Download Student Handout: PDF format or Word format