This document discusses chromosome movement during meiosis and mitosis. It includes activities to teach students about meiosis using a chromosome dance and case study. The activities address multiple learning styles and have students work cooperatively. Diagrams show chromosome behavior in mitosis and meiosis, including DNA replication, pairing of homologous chromosomes, and separation of chromatids to form haploid gametes or identical daughter cells. Common health issues for individuals with Down syndrome are also listed.

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3. Use your noodle: Understanding the role of
chromosome movements in meiosis and mitosis.
Introduction: Biological significance
Chromosomal movement during mitosis
results in the formation of two identical daughter cells
Chromosomal movement during meiosis
results in four haploid gametes with half the number of chromosomes
as the diploid mother cell
Non-disjunction- the failure of homologous chromsomes to separate
Aneuplody: Down Syndrome
Application to human health: problems in embryonic development

4. ACTIVITY I, II, III - MEIOSIS STRIP SEQUENCE
WITH CHROMOSOME DANCE
Learning Goals Students will be able to explain the
movement of chromosomes during mitosis, meiosis, and
predict the products.
Active learning includes a strip sequence that will direct a
visual demonstration of chromosome movement. This
will be followed by clicker questions.
Diversity This activity addresses a variety of learning styles,
including auditory, visual, kinesthetic and analytical.
Students will also work cooperatively.

5. ACTIVITY 4- Case study of a Down syndrome baby with
with multiple abnormalities.
Learning Goal
Students will learn to formulate hypotheses, and design
models to test their hypotheses using data from a case
study.
Active learning Think-pair-share groups will formulate
models to explain causes of Down syndrome, and will
predict karyotypes consistent with their models.
Diversity This activity includes students that can learn by
visual, analytical and interactive styles.

6. Students by this point will have seen
a mini-lecture on the following:
- chromosomes, chromosome replication, chromatids, centromeres
- homologous chromosomes
- diploid, haploid
- gametes, zygotes
- chromosome movements in mitosis
- the life cycle: 2n  n  2n
- spindle, poles
- the salient features of meiosis

7. MEIOSIS
2n
Chromosome
from mother
Chromosome
from father
Before DNA replication

8. centromere
MEIOSIS
Sister
chromatids
centromere
Sister
chromatids
After DNA replication

9. MEIOSIS
Pairing of homologous chromosomes

10. MEIOSIS
n
n
End of meiosis I
Two cells

11. MEIOSIS
gametes
n n n n
End of meiosis II
Four cells

12. Group Activity: Place the following events in the
order they occur in meiosis:
A
B
C
• 2n cell completes DNA replication
• Sister chromatids separate
• Homologous chromosomes separate to opposite poles and cells
divide
• Homologous chromosomes pair and align in the middle of the cell
• Gametes contain a single set of chromosomes
• Daughter cells contain a single set of chromosomes, each
chromosome consists of two sister chromatids
D
E
F

13. Group Activity: Place the following events in the
order they occur in meiosis:
A
D
C
• 2n cell completes DNA replication
• Homologous chromosomes pair and align in the middle of the cell
• Homologous chromosomes separate to opposite poles and cells
divide
• Daughter cells contain a single set of chromosomes, each
chromosome consists of two sister chromatids
• Sister chromatids separate
• Gametes contain a single set of chromosomes
F
B
E

14. Acknowledgements
Group 5 Members
University of Alabama
Katrina Ramonell
Jane Rasco
Louisiana State University
Pat DiMario
University of California, Riverside
Richard Cardullo
Morris Maduro
Stony Brook University
Neta Dean
Gene Katz
Group Facilitator – Brian Manske
Pool Noodle Facilitator – Sandy Gossens

16. Fusion of gametes
sperm
egg
+
2n
zygote

17. MEIOSIS - nondisjunction
n n n-1
n+1

18. Fusion of gametes
sperm
egg
+
2n+1
zygote
(aneuploid)

19. Fusion of gametes
sperm
egg
+
2n-1
zygote
(aneuploid)

21. Use your noodle: Understanding the role
of chromosome movements in meiosis and
mitosis.

22. 1 Developmental delay -- All children with Down syndrome are
delayed, although this may not be apparent until the child is beyond infancy.
IQ scores range from 20 (severe mental retardation) to 85 (low normal).
Overall learning abilities are usually equivalent to a 6 to 8 year old child
without Down syndrome.
2 Gastrointestinal abnormalities -- 2 percent to 5 percent of
children have complete obstruction of the small bowel known as duodenal
atresia. Another 2 percent have poor movement abilities of the colon and / or
rectum known as Hirschsprung disease.
3 Hearing loss -- Some degree of hearing loss is present in 40
percent to 75 percent of children with Down syndrome. Malformations may
affect either the middle or inner ear structures. Ear infections can be a
frequent, often difficult problem to treat.
4 Eye disorders -- 60 percent of children have eye disorders
that need monitoring and treatment. Congenital cataracts (loss of
transparency of the lens of the eye), glaucoma (increased pressure within
the eye), strabismus (cross-eyed) and major refractory errors (far sighted or
near sighted) are the common problems.
5 Leukemia -- Leukemia occurs in one of every 150 children
with Down Syndrome. This is 20 times higher than the general population.
6 Thyroid disorders -- Low thyroid levels are seen in
approximately 5 percent of children with Down syndrome.

28. Application: A karyotype is a display of condensed
chromosomes arranged in pairs.

29. MITOSIS
2n
Chromosome
from mother
Chromosome
from father
Before cell division and replication

30. MITOSIS
alignment

31. MITOSIS
centromere
Sister
chromatids
centromere
Sister
chromatids
After replication

32. MITOSIS
segregation

33. MITOSIS
2n 2n
Daughter cells