Name______Period______

Meiosis & Karyotypes - An Internet Lesson

In this investigation, you will view sites that illustrate how meiosis works and how a karyotype is made. For each site answer the questions associated. You can either type out the sites listed or click on them from this document posted on www.vanellism.wikispaces.com

Site 1 (not working! Ignore this!)

Site 2 - Sumanas Inc., Animation of Meiosis

Go to http://www.sumanasinc.com/webcontent/anisamples/majorsbiology/ (click on “Meiosis”)

(Click to Animation)
12. Read the introduction. Explain the difference between sexual and asexual reproduction

13. DNA replication takes place when? ______
14. Meiosis consists of two cell divisions: ______& ______
15. The pairing of homologous chromosomes is called: ______
16. Crossing over points are called ______
17. What happens in metaphase I ______
18. What happens during anaphase I ______
19. What is interkinesis? ______
20. In prophase II, each cells is [ diploid / haploid ] (circle)
21. In metaphase II, chromosomes line up in [ single | double ] file.
22. What happens during telophase II? ______
23. (Click to Conclusion). Each of the four daughter cells produced by meiosis is [ identical / unique ]

(Click to Quiz)

24. With respect to meiosis, when does DNA replication occur? ______
25. When does crossing over occur? ______
26. During which phase do chromosomes line up along the equator? ______
27. During which phase does the nuclear membrane form around the chromosomes? ______

Site 3 - Biology in Motion - Meiosis
Go to http://www.biologyinmotion.com/ (Click on "Cell Division Exercise") (Click on "Practice Meiosis")

28. Practice moving the chromosomes. When you are confident you understand what you are doing,

proceed to number 13.

29. There are two ways in which the chromosomes can end up after meiosis. Sketch the two ways and

indicate by color, the chromosomes (use the following color codes: Purple, Dark Purple, Green,

Dark green).


Site 4: PBS: Mitosis vs. Meiosis
http://www.pbs.org/wgbh/nova/baby/ (Click "How Cells Divide" Click "Mitosis vs. Meiosis")

30. After viewing the animation, fill out the chart below, by placing a check in the box or boxes to

indicate which the event occurs in (some events might have checks for both mitosis and meiosis).

Meiosis / Mitosis
One cell division
Chromosomes pair up
Spindle fibers form
Crossing over occurs
Homologous pairs separate
Meiosis / Mitosis
Sister chromatids separate
Two cell divisions
Cytokinesis
Two identical daughter cells
Four unique daughter cells

Reviewing Chromosomes & Karyotypes

Site 5: Genetic Science Learning Center

Go to: http://learn.genetics.utah.edu/units/disorders/karyotype/ (Click on “What are chromosomes?”)

31. Chromosomes are ______, they would be over 3 feet long if stretched out from end to end.

32. Normally, humans have ______chromosomes in each ______; we each receive ______

from each parent.

33. Chromosomes are best seen during ______because at that time, they are condensed,

so they are visible.

34. Scientists can diagnose or predict ______by looking at a

person’s chromosomes.

Click on “How do scientists read chromosomes?” at the bottom of this page.

35. Scientists use 3 features to identify similarities & differences in chromosomes. List them below:

a.

b.

c.

36. Centromeres are required for ______

______

37. Do the activity on the right-hand side of the page (matching the chromosome).

Click on “Making a karyotype” at the bottom of the page.

38. A karyotype is an organized profile of a person’s ______.

Basically, it is a picture of all the chromosomes in a person’s cells.

39. Describe how scientists make a karyotype below:

______

______

Click on the button that says “organize the chromosomes into a karyotype”

40. Which chromosome pair does not match? ______Click on the pair that does not

match. Why doesn’t this pair match? ______

______

41.  What is the difference between a female and male karyotype? ______

Click on the link in the first yellow activity box “Matching up chromosomes in a karyotype.”

42.  Complete the karyotype by using the mouse to move each chromosome to its partner. When you

have completed this exercise, answer the question that pops up and then call me over to show that

you have completed the exercise.

Click on the link that says “Using karyotypes to predict genetic disorders”

43. What is an autosome ______(click on

autosome to find out).

44. When chromosomes are not distributed correctly into gametes, it can cause problems. If three

chromosomes are present in a gamete, it is called ______and if only one

chromosome of a pair is in a gamete, it is called ______.

45. Two examples of trisomy are ______and

______. An example of a monosomy is ______.

46. Down Syndrome is caused by ______

______

47. Turner Syndrome is caused by ______

______

48. Klinefelter Syndrome is caused by ______

______

49. Another issue a karyotype can detect is a ______. There are two types:

a.

b.

50. Cri du chat Syndrome is a type of ______.

Click on the “Link to quiz” in the third yellow box on the right-hand side of the page to take the short quiz on chromosomal abnormalities. When you are finished with it, print it out and attach it to your webquest.

Site 6: The University of Arizona - The Biology Project

Go to http://www.biology.arizona.edu/human_bio/activities/karyotyping/karyotyping.html

Read the information on the page, including the “assignment’ and then click on “Patient Histories.”

51. What notation would you use to characterize Patient A’s karyotype (read the information once

you’ve completed the karyotype)? ______

52. What diagnosis would you give patient A? ______

53. What notation would you use to characterize Patient B’s karyotype? ______

54. What diagnosis would you give patient B? ______

55. What notation would you use to characterize Patient C’s karyotype? ______

56. What diagnosis would you give patient C? ______