Name
Class
Period
_
FIGURE 1.
Before doing this lab, have students read sections 24:3 in the text.
24-3 What are the Stages in the Menstrual Cycle?
The human female reproductive system has several different roles to
perform. It produces a new egg each month for fertilization. It must
prepare the lining of the uterus for a new embryo if fertilization of an egg
does occur. This is accomplished by a thickening of the uterus lining.
It must shed the egg and thickened uterus lining if fertilization does not
occur. All of these events occur in a cyclic pattern each month in a sexually
mature female.
INTERPRETATION
Process Skills: interpreting data, inferring,
classifying, communicating
OBJECTIVES
In this exercise, you will:
a. review the organs that form the human female reproductive system.
b. prepare a calendar that shows the changes occurring during the human
menstrual cycle if no fertilization occurs.
c. prepare a calendar that shows the changes occurring during the human
menstrual cycle if fertiliiation occurs.
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vagina
Part. B. Changes in the Meo!ltrual Cycle; No Fertilization of Egg
l. Obtain a copy of Figure 2 from your teacher.
2. Use scissors to cut out the square diagrams in Figure 2. These diagrams show
the different stages that occur during the menstrual cycle if fertilization does not
occur.
3. Look over the calendar marked Figure 3. It describes a series of events that take
place in the female reproductive system if fertilization does not take place.
4. Match the diagrams that you cut out with the events being described in the
calendar.
5. When all diagrams have been properly matched, tape them onto the calendar in
their proper location to the right of the brackets describing the events.
Be sure students use Figure 2 models with Figure 3.
KEYWORDS
Define the following keywords:
fertilization
joining of egg and sperm cell
menstrual cycle
ovary
oviduct
uterus
monthly changes that take place in female reproductive system
female sex organ that produces eggs
tubelike organ that connect the ovaries to uterus
muscular organ in which fertilized egg develops
•
MATERIALS
You will need to photocopy Figures 2 and 4 for students.
scissors
tape
You may wish to have students work in groups.
PROCEDURE
Part A. Review of the Female Reproductive System
l. Use the following parts and their description for help in properly labeling Figure l.
NOTE: The diagram is l/3 natural size.
a. ovary-two are present, round in shape
b. egg-small cells present within ovary
c. uterus-large muscle, V-shaped, largest part of reproductive system
d. oviduct-thin tube connecting each ovary to uterus
e. uterus lining-inner wall or lining of uterus
Part C. Changes in the Menstrual Cycle; Fertilized Does Occur
l. Obtain a copy of Figure 4 from your teacher.
2. Use scissors to cut out the square diagrams in Figure 4. These diagrams show
the different stages that occur during the menstrual cycle if fertilization does
occur.
3. Look over the calendar marked Figure 5. It describes a series of events that take
place in the female reproductive system if fertilization does take place.
4. Match the diagrams that you cut out with the events being described in the
calendar.
.
5. When all diagramJ have been properly matched, tape them onto the calendar in
their proper location to the right of the brackets describing the events. ­
Be sure students use Figure 4 models with Figure 5.
Advise students that Figures 2 and 4 are not drawn in their proper sequence. Students will have
to determine the proper order of events based on information provided on the calendars. You
may wish to check calendars before students tape models in place to verify that models are
positioned in correct sequence.
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Name
Class
Period
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QUESTIONS
1. Describe the role or function of the following:
a. ovary produces egg cells
b. uterus lining serves as a surface upon which young embryo can attach
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a. from day 15-28 if no fertilization occurs.
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b. egg in ovary continues to mature
5. Describe what happens to the egg during the menstrual cycle on day 14.
6. Describe the changes that take place to an egg
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4. Describe the changes that take place during the menstrual cycle from day 5-13
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3. Describe the changes that take place during the menstrual cycle from day 1-4 to
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