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Glencoe Science
Chapter Resources
Cell Reproduction
Includes:
Reproducible Student Pages
ASSESSMENT
TRANSPARENCY ACTIVITIES
✔ Chapter Tests
✔ Section Focus Transparency Activities
✔ Chapter Review
✔ Teaching Transparency Activity
HANDS-ON ACTIVITIES
✔ Assessment Transparency Activity
✔ Lab Worksheets for each Student Edition Activity
Teacher Support and Planning
✔ Laboratory Activities
✔ Content Outline for Teaching
✔ Foldables–Reading and Study Skills activity sheet
✔ Spanish Resources
✔ Teacher Guide and Answers
MEETING INDIVIDUAL NEEDS
✔ Directed Reading for Content Mastery
✔ Directed Reading for Content Mastery in Spanish
✔ Reinforcement
✔ Enrichment
✔ Note-taking Worksheets
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Glencoe Science
Photo Credits
Section Focus Transparency 1: (t) Royalty Free/CORBIS, (b) Dwight R. Kuhn;
Section Focus Transparency 2: (tl) William Hamilton/SuperStock, (tr) Animals Animals/Lynn Stone,
(b) Animals Animals/Bates Littlehales; Section Focus Transparency 3: Yann Arthus-Bertrand/CORBIS
Copyright © by The McGraw-Hill Companies, Inc. All rights reserved.
Permission is granted to reproduce the material contained herein on the condition
that such material be reproduced only for classroom use; be provided to students,
teachers, and families without charge; and be used solely in conjunction with the
Cell Reproduction program. Any other reproduction, for use or sale, is prohibited
without prior written permission of the publisher.
Send all inquiries to:
Glencoe/McGraw-Hill
8787 Orion Place
Columbus, OH 43240-4027
ISBN 0-07-867094-2
Printed in the United States of America.
1 2 3 4 5 6 7 8 9 10 024 09 08 07 06 05 04
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Table of Contents
To the Teacher
Reproducible Student Pages
■
iv
Hands-On Activities
MiniLAB: Modeling Mitosis . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3
MiniLAB: Try at Home Modeling DNA Replication . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4
Lab: Mitosis in Plant Cells . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5
Lab: Use the Internet Mutations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7
Laboratory Activity 1: Modeling Cell Division in Early Development . . . . . . . . . . . . . . . . . . . . . . . . . 9
Laboratory Activity 2: Examining Models of Chromosomes. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11
Foldables: Reading and Study Skills . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15
■
Meeting Individual Needs
Extension and Intervention
Directed Reading for Content Mastery . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17
Directed Reading for Content Mastery in Spanish . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21
Reinforcement . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 25
Enrichment . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 28
Note-taking Worksheet . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 31
■
Assessment
Chapter Review . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 35
Chapter Test . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 37
■
Transparency Activities
Section Focus Transparency Activities. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 42
Teaching Transparency Activity . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 45
Assessment Transparency Activity . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 47
Teacher Support and Planning
Content Outline for Teaching . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . T2
Spanish Resources . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . T5
Teacher Guide and Answers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . T9
Additional Assessment Resources available with Glencoe Science:
•
•
•
•
•
•
•
•
•
ExamView® Pro Testmaker
Assessment Transparencies
Performance Assessment in the Science Classroom
Standardized Test Practice Booklet
MindJogger Videoquizzes
Vocabulary PuzzleMaker at msscience.com
Interactive Chalkboard
The Glencoe Science Web site at: msscience.com
An interactive version of this textbook along with assessment resources are available
online at: mhln.com
iii
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To the Teacher
This chapter-based booklet contains all of the resource materials to help you teach
this chapter more effectively. Within you will find:
Reproducible pages for
■ Student Assessment
■ Hands-on Activities
■ Meeting Individual Needs (Extension and Intervention)
■ Transparency Activities
A teacher support and planning section including
■ Content Outline of the chapter
■ Spanish Resources
■ Answers and teacher notes for the worksheets
Hands-On Activities
Laboratory Activities: These activities do not require elaborate supplies or extensive pre-lab
preparations. These student-oriented labs are designed to explore science through a stimulating yet simple and relaxed approach to each topic. Helpful comments, suggestions, and
answers to all questions are provided in the Teacher Guide and Answers section.
Foldables: At the beginning of each chapter there is a Foldables: Reading & Study Skills
activity written by renowned educator Dinah Zike that provides students with a tool that
they can make themselves to organize some of the information in the chapter. Students may
make an organizational study fold, a cause and effect study fold, or a compare and contrast
study fold, to name a few. The accompanying Foldables worksheet found in this resource
booklet provides an additional resource to help students demonstrate their grasp of the
concepts. The worksheet may contain titles, subtitles, text, or graphics students need to
complete the study fold.
Meeting Individual Needs (Extension and Intervention)
Directed Reading for Content Mastery: These worksheets are designed to provide students
with learning difficulties with an aid to learning and understanding the vocabulary and
major concepts of each chapter. The Content Mastery worksheets contain a variety of formats
to engage students as they master the basics of the chapter. Answers are provided in the
Teacher Guide and Answers section.
iv
Copyright © Glencoe/McGraw-Hill, a division of the McGraw-Hill Companies, Inc.
MiniLAB and Lab Worksheets: Each of these worksheets is an expanded version of each lab
and MiniLAB found in the Student Edition. The materials lists, procedures, and questions
are repeated so that students do not need their texts open during the lab. Write-on rules are
included for any questions. Tables/charts/graphs are often included for students to record
their observations. Additional lab preparation information is provided in the Teacher Guide
and Answers section.
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Directed Reading for Content Mastery (in Spanish): A Spanish version of the Directed
Reading for Content Mastery is provided for those Spanish-speaking students who are
learning English.
Reinforcement: These worksheets provide an additional resource for reviewing the concepts of the chapter. There is one worksheet for each section, or lesson, of the chapter.
The Reinforcement worksheets are designed to focus primarily on science content and less
on vocabulary, although knowledge of the section vocabulary supports understanding of
the content. The worksheets are designed for the full range of students; however, they will
be more challenging for your lower-ability students. Answers are provided in the Teacher
Guide and Answers section.
Enrichment: These worksheets are directed toward above-average students and allow them
to explore further the information and concepts introduced in the section. A variety of
formats are used for these worksheets: readings to analyze; problems to solve; diagrams
to examine and analyze; or a simple activity or lab which students can complete in the
classroom or at home. Answers are provided in the Teacher Guide and Answers section.
Note-taking Worksheet: The Note-taking Worksheet mirrors the content contained in the
teacher version—Content Outline for Teaching. They can be used to allow students to take
notes during class, as an additional review of the material in the chapter, or as study notes
for students who have been absent.
Copyright © Glencoe/McGraw-Hill, a division of the McGraw-Hill Companies, Inc.
Assessment
Chapter Review: These worksheets prepare students for the chapter test. The
Chapter Review worksheets cover all major vocabulary, concepts, and objectives
of the chapter. The first part is a vocabulary review and the second part is a concept review.
Answers and objective correlations are provided in the Teacher Guide and Answers section.
Chapter Test: The Chapter Test requires students to use process skills and understand content.
Although all questions involve memory to some degree, you will find that your students will
need to discover relationships among facts and concepts in some questions, and to use higher
levels of critical thinking to apply concepts in other questions. Each chapter test normally
consists of four parts: Testing Concepts measures recall and recognition of vocabulary and
facts in the chapter; Understanding Concepts requires interpreting information and more
comprehension than recognition and recall—students will interpret basic information and
demonstrate their ability to determine relationships among facts, generalizations, definitions,
and skills; Applying Concepts calls for the highest level of comprehension and inference;
Writing Skills requires students to define or describe concepts in multiple sentence answers.
Answers and objective correlations are provided in the Teacher Guide and Answers section.
Transparency Activities
Section Focus Transparencies: These transparencies are designed to generate interest
and focus students’ attention on the topics presented in the sections and/or to assess
prior knowledge. There is a transparency for each section, or lesson, in the Student Edition.
The reproducible student masters are located in the Transparency Activities section. The
teacher material, located in the Teacher Guide and Answers section, includes Transparency
Teaching Tips, a Content Background section, and Answers for each transparency.
v
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Teaching Transparencies: These transparencies relate to major concepts that will benefit
from an extra visual learning aid. Most of these transparencies contain diagrams/photos
from the Student Edition. There is one Teaching Transparency for each chapter. The Teaching
Transparency Activity includes a black-and-white reproducible master of the transparency
accompanied by a student worksheet that reviews the concept shown in the transparency.
These masters are found in the Transparency Activities section. The teacher material includes
Transparency Teaching Tips, a Reteaching Suggestion, Extensions, and Answers to Student
Worksheet. This teacher material is located in the Teacher Guide and Answers section.
Assessment Transparencies: An Assessment Transparency extends the chapter content and
gives students the opportunity to practice interpreting and analyzing data presented in
charts, graphs, and tables. Test-taking tips that help prepare students for success on standardized tests and answers to questions on the transparencies are provided in the Teacher
Guide and Answers section.
Teacher Support and Planning
Content Outline for Teaching: These pages provide a synopsis of the chapter by section,
including suggested discussion questions. Also included are the terms that fill in the blanks
in the students’ Note-taking Worksheets.
Copyright © Glencoe/McGraw-Hill, a division of the McGraw-Hill Companies, Inc.
Spanish Resources: A Spanish version of the following chapter features are included in this
section: objectives, vocabulary words and definitions, a chapter purpose, the chapter Activities, and content overviews for each section of the chapter.
vi
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Reproducible
Student Pages
Reproducible Student Pages
■
Hands-On Activities
MiniLAB: Modeling Mitosis . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3
MiniLAB: Try at Home Modeling DNA Replication. . . . . . . . . . . . . . . 4
Lab: Mitosis in Plant Cells. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5
Lab: Use the Internet Mutations. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7
Laboratory Activity 1: Modeling Cell Division in Early Development . 9
Laboratory Activity 2: Examining Models of Chromosomes . . . . . . . . 11
Foldables: Reading and Study Skills. . . . . . . . . . . . . . . . . . . . . . . . . . 15
■
Meeting Individual Needs
Extension and Intervention
Directed Reading for Content Mastery . . . . . . . . . . . . . . . . . . . . . . . 17
Directed Reading for Content Mastery in Spanish . . . . . . . . . . . . . . 21
Reinforcement . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 25
Enrichment. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 28
Note-taking Worksheet . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 31
■
Assessment
Chapter Review . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 35
Chapter Test . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 37
■
Transparency Activities
Section Focus Transparency Activities . . . . . . . . . . . . . . . . . . . . . . . . 42
Teaching Transparency Activity . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 45
Assessment Transparency Activity . . . . . . . . . . . . . . . . . . . . . . . . . . . 47
Cell Reproduction
1
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Hands-On Activities
Hands-On
Activities
2 Cell Reproduction
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Date
Class
Hands-On Activities
Name
Modeling Mitosis
Procedure
1. Make models of cell division using materials supplied by your teacher.
2. Use four chromosomes in your model.
3. When finished, arrange the models in the order in which mitosis occurs.
Analysis
1. In which steps is the nucleus visible?
Copyright © Glencoe/McGraw-Hill, a division of the McGraw-Hill Companies, Inc.
2. How many cells does a dividing cell form?
Cell Reproduction
3
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Name
Date
Class
Procedure
1. Suppose you have a segment of DNA that is six nitrogen base pairs in
length. In the space below, using the letters A, T, C, and G, write a combination of six pairs, remembering that A and T are always a pair and C and G
are always a pair.
2. Duplicate your segment of DNA. In the space below, diagram how this
happens and show the new DNA segments.
Analysis
Compare the order of bases of the original DNA to the new DNA molecules.
4 Cell Reproduction
Copyright © Glencoe/McGraw-Hill, a division of the McGraw-Hill Companies, Inc.
Hands-On Activities
Modeling DNA Replication
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Name
Date
Class
Hands-On Activities
Mitosis in Plant Cells
Lab Preview
Directions: Answer these questions before you begin the Lab.
1. Why should you examine the root tip under high and low power?
2. What is the root cap?
Reproduction of most cells in plants and animals uses mitosis and cell
division. In this lab, you will study mitosis in plant cells by examining
prepared slides of onion root-tip cells.
Real-World Question
Procedure
How can plant cells in different stages of
mitosis be distinguished from each other?
1. Obtain a prepared slide of cells from an onion
root tip.
2. Set your microscope on low power and
examine the slide. The large, round cells at
the root tip are called the root cap. Move
the slide until you see the cells just behind
the root cap. Turn to the high-power
objective.
3. Find an area where you can see the most
stages of mitosis. Count and record how
many cells you see in each stage. Record
your data on the next page.
4. Return the nosepiece to low power.
Remove the onion root-tip slide.
Materials
Copyright © Glencoe/McGraw-Hill, a division of the McGraw-Hill Companies, Inc.
prepared slide of an onion root tip
microscope
Goals
■
■
Compare cells in different stages of mitosis
and observe the location of their
chromosomes.
Observe what stage of mitosis is most
common in onion root tips.
Safety Precautions
Root cap
Zone of cell division
Cell Reproduction
5
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Name
Date
Class
(continued)
Stage of Mitosis
Number of
Percent of
Cells Observed Cells Observed
Prophase
Metaphase
Anaphase
Telophase
Total
100%
Conclude and Apply
1. Compare the cells in the region behind the root cap to those in the root cap.
2. Calculate the percent of cells found in each stage of mitosis. Infer which stage of mitosis takes
the longest period of time.
Communicating Your Data
Write and illustrate a story as if you were a cell undergoing mitosis. Share your story with
your class. For more help, refer to the Science Skill Handbook.
6 Cell Reproduction
Copyright © Glencoe/McGraw-Hill, a division of the McGraw-Hill Companies, Inc.
Hands-On Activities
Data and Observations
Number of Root-Tip Cells Observed
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Name
Date
Class
Use the Internet
Hands-On Activities
Mutations
Mutations can result in dominant or recessive genes. A recessive characteristic can appear only
if an organism has two recessive genes for that characteristic. However, a dominant
characteristic can appear if an organism has one or two dominant genes for that characteristic.
Why do some mutations result in more common traits while others do not?
Real-World Question
Follow Your Plan
Form a hypothesis about how a mutation can
become a common trait.
1. Make sure your teacher approves your plan
before you start.
2. Visit the link shown below to access different Web sites for information about mutations and genetics.
3. Decide if a mutation is beneficial, harmful,
or neither. Record your data in your Science Journal.
Goals
■
■
■
■
Observe traits of various animals.
Research how mutations become traits.
Gather data about mutations.
Make a frequency table of your findings and
communicate them to other students.
Data Source
Copyright © Glencoe/McGraw-Hill, a division of the McGraw-Hill Companies, Inc.
Visit msscience.com for
more information on
common genetic traits in different animals,
recessive and dominant genes, and data from
other students.
Make a Plan
1. Observe common traits in various animals, such as household pets or animals
you might see in a zoo.
2. Learn what genes carry these traits in each
animal.
3. Research the traits to discover which ones are
results of mutations. Are all mutations dominant? Are any of these mutations beneficial?
Analyze Your Data
1. Record in your Science Journal a list of
traits that are results of mutations.
2. Describe an animal, such as a pet or an
animal you’ve seen in the zoo. Point out
which traits are known to be the result of a
mutation.
3. Make a chart that compares recessive
mutations to dominant mutations. Which
are more common?
4. Share your data with other students by
posting it at the link shown on the next
page.
Cell Reproduction
7
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Name
Date
Class
(continued)
1. Compare your findings to those of your classmates and other data at the link shown below.
What were some of the traits your classmates found that you did not? Which were the most
common?
2. Look at your chart of mutations. Are all mutations beneficial? When might a mutation be
harmful to an organism?
3. Predict how your data would be affected if you had performed this lab when one of these common mutations first appeared. Do you think you would see more or less animals with this trait?
4. Mutations occur every day but we only see a few of them. Infer how many mutations over
millions of years can lead to a new species.
Communicating Your Data
Find this lab using the link below. Post your data in the table provided. Combine your data
with that of other students and make a chart that shows all of the data.
msscience.com
8 Cell Reproduction
Copyright © Glencoe/McGraw-Hill, a division of the McGraw-Hill Companies, Inc.
Hands-On Activities
Conclude and Apply
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Name
Date
Modeling Cell Division in Early
Development
Hands-On Activities
1
Laboratory
Activity
Class
Every person starts out as a single cell. Cell division is responsible for the development of a
baby from the single cell. As the single cell begins developing, cell division results in exponential
growth in the number of cells present. Exponential growth is growth that occurs at an everincreasing rate. On a graph, exponential growth is represented by a J-shaped curve.
Strategy
You will model how cell division results in exponential growth in the number of cells in a
developing human.
You will determine why exponential growth cannot continue indefinitely during human
development.
You will infer why uncontrolled cell division, which occurs in cancer, can be so harmful to
human health.
Materials
uncooked rice
paper cups (11)
graph paper
Copyright © Glencoe/McGraw-Hill, a division of the McGraw-Hill Companies, Inc.
Procedure
1. Obtain a container of uncooked rice from
your teacher. Each grain of rice represents
one human cell.
2. Place one grain of rice in a paper cup. This
grain of rice represents the single cell that
results when sperm and egg unite.
3. Label paper cups 1 through 10, and place
them in a row next to the cup containing
the original cell. During the first 10 cell
divisions, the cells in the developing
human all have the same cell-cycle length.
4. Place two grains of rice into cup 1 to
represent the number of cells present after
the original cell undergoes the first round
of mitosis. Record the number 2 in the
table in the Data and Observations section.
5. Place grains of rice into cup 2 to represent
the number of cells that will be present
after the second round of mitosis. Record
the number of cells in your data table.
6. Repeat step 5 for cups 3 through 10.
7. Using your data and graph paper, make a
line graph that shows the growth in the
numbers of cells. Label the x-axis Number
of cell divisions and the y-axis Number of
cells.
Cell Reproduction
9
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Name
Date
Class
Laboratory Activity 1 (continued)
Growth in Cell Number Due to Mitosis
Number of
mitotic
divisions
Resulting number of cells
Number of
mitotic
divisions
1
6
2
7
3
8
4
9
5
10
Resulting number of cells
Questions and Conclusions
1. Initially all of the cells in a developing human have the same cell-cycle length. After the
eleventh round of mitosis, groups of cells begin to have different cell-cycle lengths. What step
of the cell cycle is likely to be longer in cells with a longer cell cycle?
2. Could the type of growth you modeled with grains of rice continue indefinitely in a developing
human? Explain your answer.
3. Cancer results from uncontrolled cell division. Using your results from this activity, infer why
cancer can have such a serious effect on human health.
Strategy Check
Can you describe exponential growth?
Can you graphically represent exponential growth?
Can you describe how cell division results in exponential growth?
10 Cell Reproduction
Copyright © Glencoe/McGraw-Hill, a division of the McGraw-Hill Companies, Inc.
Hands-On Activities
Data and Observations
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Date
2
Laboratory
Activity
Class
Examining Models of
Chromosomes
Models of the chromosomes of the imaginary Leksak bird can be found at the end of this
lab. The dark bands on these chromosome models are genes. Most cells in this bird’s body contain
the same number and type of chromosomes. The importance of genes to all living things, and to
the Leksak bird as well, is that they control all inherited traits. Chromosomes are important
because they are the carriers of these genes.
Strategy
You will cut out and pair chromosome models of the Leksak bird.
You will determine what type of change occurs in the number of chromosomes when a cell
divides by mitosis and meiosis.
Materials
scissors
Copyright © Glencoe/McGraw-Hill, a division of the McGraw-Hill Companies, Inc.
Procedure/Data and Observations
1. Cut out each chromosome model in
Figure 1.
2. Fold each paper model in half along
dotted lines.
3. Match in pairs as many chromosome
models as possible. A chromosome pair
must match in length as well as in number
and location of genes. The lines on the
chromosome models represent genes.
4. Answer questions 1 through 4 in Questions
and Conclusions before proceeding further.
5. Cut each chromosome model in half
along the dotted line. Make two piles of
chromosome halves. Put one half of each
chromosome in one pile and the other
half in the second pile.
6. Compare the chromosomes in the first
pile with those in the second pile.
Cell division includes a process called mitosis
that occurs in most living things. During
mitosis, a cell’s nucleus divides into two
nuclei. The cutting of each chromosome
model and separating them into two piles is
similar to what happens in a living cell during
cell division. The two piles of chromosome
models represent two new cells. (Each chromosome duplicates itself and the two halves
then separate.)
7. Before proceeding, answer questions 5
and 6 in Questions and Conclusions.
8. Place all identical chromosome models
together in separate groups. You should
have six groups of models.
9. Take a group of matched chromosomes
and separate them into four piles. Take a
second group of matched chromosomes
and place one chromosome from the
group into each of the four piles.
10. Continue this sorting until all chromosome models, including the unmatched
chromosome models, have been separated
into the four piles. Each pile of chromosome models represents a sex cell.
A process called meiosis occurs in some living
things. During meiosis, a cell’s nucleus divides
twice so that one diploid cell divides to produce four haploid cells. Each new cell produced by this process is called a sex cell (egg
or sperm).
Cell Reproduction
11
Hands-On Activities
Name
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Name
Date
Class
Laboratory Activity 2 (continued)
1. How many chromosomes can be found in each of the Leksak bird’s cells?
2. How many matched pairs of chromosomes are there in each cell?
3. How many unmatched chromosomes are there in each cell?
4. Do the genes on each matched pair of chromosomes also match?
5. After separating the chromosome model halves into two piles, how many models are found in
each pile?
6. How many chromosomes are found in Leksak sex cells?
7. Do any chromosomes match one another in a sex cell?
8. Male Leksak birds have six matched pairs of chromosomes and one unmatched pair of chromosomes. Female Leksak birds have seven matched pairs of chromosomes. Were the chromosomes in our bird taken from a male or a female?
9. Are all cells produced by mitosis exactly alike, chromosome for chromosome? Gene for gene?
Explain why.
10. How does the number of chromosomes in sex cells compare to the number of chromosomes
in cells formed during mitosis?
11. Explain two ways in which sex cells differ from all other cells.
Strategy Check
Did you cut out and match in pairs the chromosome models of the Leksak bird?
Did you determine the types of changes that occur in the number of chromosomes
when a cell undergoes mitosis or meiosis?
12 Cell Reproduction
Copyright © Glencoe/McGraw-Hill, a division of the McGraw-Hill Companies, Inc.
Hands-On Activities
Questions and Conclusions
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Name
Date
Class
Figure 1
Copyright © Glencoe/McGraw-Hill, a division of the McGraw-Hill Companies, Inc.
Models of chromosomes for the imaginary Leksak bird after duplication in the interphase period
of the cell cycle.
Cell Reproduction
13
Hands-On Activities
Laboratory Activity 2 (continued)
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Name
Date
Class
Hands-On Activities
Cell Reproduction
Directions: Use this page to label your Foldable at the beginning of the chapter.
Chromatid pairs line up
in the center of the cell.
Each day, cells in your
body wear out and are
replaced.
Copyright © Glencoe/McGraw-Hill, a division of the McGraw-Hill Companies, Inc.
The chromatid pairs are
visible and the spindle
begins to form.
The chromosomes
duplicate.
The chromosomes
separate.
The cytoplasm begins
to separate.
You grow because cell
division increases the
total number of cells in
your body.
Cell Reproduction
15
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Meeting Individual Needs
Meeting Individual
Needs
16 Cell Reproduction
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Name
Date
Directed Reading for
Content Mastery
Class
Overview
Cell Reproduction
Directions: Complete the concept map using the terms in the list below.
metaphase
telophase
prophase
interphase
mitosis ends, the cytoplasm
divides, and each new cell
enters a period called
1.
Meeting Individual Needs
mitosis begins,
2.
chromatoid pairs
are now visible,
leading to
chromosomes
have separated
Copyright © Glencoe/McGraw-Hill, a division of the McGraw-Hill Companies, Inc.
3.
anaphase
pairs of
chromatoids
line up in the
center of the
cell
Directions: Use the five terms in the concept map to identify the steps of the cell cycle below.
Description
Step of Cell Cycle
4. Spindle fibers start to disappear, nuclear membrane forms,
and cytoplasm begins to divide.
5. Chromatid pairs are fully visible, the nucleolus and the nuclear
membrane disintegrate, and spindle fibers begin to form.
6. Chromatid pairs line up across center of cell, the centromere
of each pair attaches to spindle fibers.
7. Each chromatid pair splits at the centromere and separates
to opposite ends of the cell, where they become identical
chromosomes.
8. Cell grows and makes copies of its hereditary material.
Cell Reproduction
17
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Name
Date
Directed Reading for
Content Mastery
Section 1
■
Section 2
■
Class
Cell Division and
Mitosis
Sexual Reproduction
and Meiosis
Directions: Study the diagram. Then answer the following questions.
Prophase I
Metaphase I
Anaphase I
Telophase I
Meiosis II
Meiosis I
Interphase
Prophase II
Metaphase II
Anaphase II
Telophase II
of meiosis I?
2. What happens to the chromosomes of a cell in order for meiosis to begin?
3. Meiosis I is the same as what other reproductive process?
4. Meiosis I begins with one cell. How many cells are formed by the end of meiosis II?
5. At the end of meiosis II, each of the haploid sex cells has only half the number of
chromosomes as the original diploid cell. Why is this important?
18 Cell Reproduction
Copyright © Glencoe/McGraw-Hill, a division of the McGraw-Hill Companies, Inc.
1. Meiosis begins with one cell. How many cells are formed by the end
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Name
Date
Directed Reading for
Content Mastery
Section 3
Class
■
DNA
Directions: The mRNA strand shown below is preparing to make proteins from amino acids. tRNA molecules
bring the amino acids to the mRNA strand for the rRNA to use in making proteins. Circle the tRNA molecule that
will attach to the mRNA strand. Remember that cytosine (C) pairs with guanine (G), and adenine (A) pairs with
uracil (U).
AA
Meeting Individual Needs
AA
tRNA
C
U
G
C
U
C
A
G
A
Copyright © Glencoe/McGraw-Hill, a division of the McGraw-Hill Companies, Inc.
mRNA
Directions: Study the above diagram. Then answer the following questions.
1. How did you know which tRNA molecule would attach to the mRNA strand?
2. Suppose that one of the bases on the mRNA was changed. Would the same tRNA
molecule still attach to the strand? Explain your answer.
Cell Reproduction
19
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Name
Date
Directed Reading for
Content Mastery
Class
Key Terms
Cell Reproduction
Directions: Select the term from the following list that matches each description.
asexual
genes
RNA
chromosome
haploid
sexual
diploid
meiosis
sperm
DNA
mitosis
zygote
eggs
mutation
fertilization
1. Many cells in your body grow and divide every day by
what process?
2. What structure in a cell’s nucleus holds the hereditary
information?
3. term for the joining of an egg and sperm
4. the sections of DNA that contain instructions for
producing specific proteins
5. What are male sex cells called?
7. the term for any permanent change in a gene or
chromosome
8. the type of reproduction that produces a new organism;
with identical chromosomes to those of the parent organism.
9. the process that produces haploid sex cells
10. an organism grows and functions by following the
information in this code
11. the term for female sex cells
12. Cells with pairs of chromosomes are this.
13. type of reproduction that requires the joining of two
sex cells
14. This type of nucleic acid carries the information needed
to make proteins.
15. cells that do not have pairs of chromosomes (sex cells)
20 Cell Reproduction
Copyright © Glencoe/McGraw-Hill, a division of the McGraw-Hill Companies, Inc.
6. What cell forms when an egg and a sperm join?
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Nombre
Fecha
Lectura dirigida para
Dominio del contenido
Clase
Sinopsis
Reproducción celular
Instrucciones: Completa el mapa de conceptos usando los siguientes términos.
metafase
telofase
profase
la mitosis termina, el citoplasma
se divide y cada nueva célula
entra en una fase llamada
empieza la mitosis
1.
2.
los cromosomas se
han separado
los pares de cromátides ahora
son visibles, llevando a la
Copyright © Glencoe/McGraw-Hill, a division of the McGraw-Hill Companies, Inc.
3.
anafase
los pares de
cromátides
se alínean en el
centro de la célula
Instrucciones: Usa los cinco términos del mapa de conceptos para identificar las fases de la mitosis.
Fases de la mitosis
Descripción
4. Las fibras del huso comienzan a desaparecer, se forma la
membrana nuclear y el citoplasma comienza a dividirse.
5. Los pares de cromátides son visibles, el nucléolo y la membrana nuclear se desintegran y comienzan a formarse las fibras del
huso.
6. Los pares de cromátides se alinean en el centro de la célula y
el centrómero de cada par se adhiere a las fibras del huso.
7. Cada centrómero se divide y cada par de cromátides se alinea en el centro de la célula, donde se convierten en cromosomas idénticos.
8. La célula crece y hace copias de su material hereditario.
Reproducción celular
21
Satisface las necesidades individuales
la interfase
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Nombre
Fecha
Lectura dirigida para
Dominio del contenido
Clase
Sección 1
■
Sección 2
■
División celular
y mitosis
Reproducción
sexual y meiosis
Instrucciones: Estudia el diagrama. Luego responde las preguntas.
Profase I
Metafase I
Anafase I
Telofase I
Meiosis II
Profase II
Metafase II
Anafase II
Telofase II
1. La meiosis comienza con una célula. ¿Cuántas células se forman al final de la
meiosis I?
2. ¿Qué les ocurre a los cromosomas de una célula para que se inicie la meiosis?
3. ¿Qué otro proceso reproductor es igual la meiosis I?
4. La meiosis I comienza con una sola célula. ¿Cuántas células se forman al final de la
meiosis II?
5. Al final de la meiosis II, cada célula sexual haploide tiene sólo la mitad de cromosomas que la célula diploide original. ¿Por qué es esto importante?
22 Reproducción celular
Copyright © Glencoe/McGraw-Hill, a division of the McGraw-Hill Companies, Inc.
Satisface las necesidades individuales
Meiosis I
Interfase
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Nombre
Fecha
Sección 3
Lectura dirigida para
Clase
■
DNA
Dominio del contenido
Instrucciones: El filamento mRNA que se muestra se está preparando para producir proteínas a partir de
aminoácidos. Las moléculas tRNA llevan los aminoácidos al filamento mRNA para que el rRNA lo utilice para
elaborar proteínas. Encierra en un círculo la molécula que se adherirá al filamento mRNA. Recuerda que la
citosina (C) se aparea con la guanina (G) y la adenina (A) se aparea con el uracil (U).
AA
Satisface las necesidades individuales
AA
tRNA
C
U
G
C
U
C
A
G
A
Copyright © Glencoe/McGraw-Hill, a division of the McGraw-Hill Companies, Inc.
mRNA
Instrucciones: Estudia el diagrama anterior. Luego contesta las preguntas.
1. ¿Cómo supiste cuál molécula tRNA se adheriría al filamento mRNA?
2. Supón que se cambió una de las bases en el mRNA. ¿Crees que la misma
molécula tRNA se adheriría al filamento? Explica tu respuesta.
Reproducción celular
23
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Nombre
Fecha
Lectura dirigida para
Dominio del contenido
Clase
Términos claves
Reproducción celular
Instrucciones: Coordina la descripción con el término correcto de la lista.
asexual
genes
RNA
cromosoma
haploide
sexual
diploide
meiosis
espermatozoide
DNA
mitosis
cigoto
óvulos
mutación
fecundación
Satisface las necesidades individuales
1. ¿Mediante qué proceso muchas células en tu cuerpo crecen y se dividen diariamente?
2. ¿Qué estructura en el núcleo de la célula lleva la información hereditaria?
3. Término que define la unión de un óvulo y un
espermatozoide.
4. Estas secciones de DNA contienen instrucciones para
producir proteínas específicas.
5. ¿Cómo se llaman las células sexuales masculinas?
7. término para cualquier cambio permanente en un gen o
en un cromosoma
8. Tipo de reproducción que produce nuevos organismos;
con cromosomas idénticos al organismo progenitor.
9. el proceso que produce células sexuales haploides
10. Un organismo crece y funciona siguiendo la información de este código.
11. término para las células sexuales femeninas
12. células con pares de cromosomas
13. Tipo de reproducción que requiere la unión de dos
células sexuales.
14. Este tipo de ácido nucleico lleva la información necesaria para producir proteínas.
15. Células que no tienen pares de cromosomas (células
sexuales).
24 Reproducción celular
Copyright © Glencoe/McGraw-Hill, a division of the McGraw-Hill Companies, Inc.
6. ¿Qué célula se forma de la unión de un óvulo y un
espermatozoide?
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Name
1
Date
Reinforcement
Class
Cell Division and Mitosis
1. ________________________
2. ________________________
3. ________________________
4. ________________________
Meeting Individual Needs
Directions: Study the following diagrams. Then label the appropriate steps of mitosis.
Directions: Answer the following questions on the lines provided.
Copyright © Glencoe/McGraw-Hill, a division of the McGraw-Hill Companies, Inc.
5. Once chromosomes have been copied during interphase, the cell is ready to begin what process?
6. During metaphase, the centromeres attach to what structures?
7. Why doesn’t the cell membrane pinch in to divide the cytoplasm telophase in plant cells?
8. How many chromosomes does each new cell contain after mitosis if the original cell had 52
original cell chromosomes?
9. Why is mitosis a form of asexual reproduction?
10. What are three types of asexual reproduction?
11. Why are skin cells undergoing mitosis continuously?
12. What types of cells in your body are no longer undergoing mitosis?
13. What phase of the cell cycle are the types of cells in Question 12?
Cell Reproduction
25
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Name
2
Date
Reinforcement
Class
Sexual Reproduction
and Meiosis
Directions: Study the following diagrams. Then label the appropriate steps of meiosis.
2.
3.
4.
Directions: Answer the following questions on the lines provided.
5. In what way is meiosis II similar to mitosis?
6. What is a cell with pairs of chromosomes called? A cell with no pairs (single set)? of
chromosomes?
7. Do centromeres divide at anaphase I or II?
8. Starting with one diploid cell, how many haploid sperm cells have formed after both phases of
meiosis have been completed?
9. How are sex cells different from other cells in the body?
10. What happens during fertilization?
26 Cell Reproduction
Copyright © Glencoe/McGraw-Hill, a division of the McGraw-Hill Companies, Inc.
Meeting Individual Needs
1.
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Name
3
Date
Reinforcement
Class
DNA
Directions: Answer the following questions on the lines provided.
1. Write the letter of the DNA bases that pair with the following DNA strand.
T:
G:
A:
Meeting Individual Needs
T:
C:
2. Write the name of the RNA bases that pair with the following DNA strand.
A:
C:
T:
G:
A:
Copyright © Glencoe/McGraw-Hill, a division of the McGraw-Hill Companies, Inc.
3. What structure contains the instructions for making specific protein?
4. What makes up the sides of the “ladder” of a DNA molecule?
5. How is RNA different from DNA?
6. What role does RNA play in cell life?
7. What are the three kinds of RNA and what does each do?
8. What can cause mutations?
Cell Reproduction
27
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Name
Enrichment
Class
True to Foram
Meeting Individual Needs
The cells of the human body are called
eukaryotic cells. Eukaryotic cells must reproduce and divide in order to make new cells.
You are familiar with the cells of your body,
but millions of eukaryotic cells are complete
living organisms all by themselves. Single-celled
organisms live, feed, and reproduce by mitosis,
just like the cells in your body.
Shedding their Shells
Single Cell with a Shell
Foram Mitosis
An interesting type of single-celled animal is
called a foraminifer (for–a–min–i–fer). This very
long word belongs to a very tiny animal.
Foraminifers, or forams for short, are related to
amoebas, single-celled organisms that have no
firm body shape. In contrast to amoebas, forams
are surrounded by little shells they make from
fluids on the outside of their bodies. These shells
are called “tests.” Forams make tests of many different shapes and sizes. The Egyptian pyramids
are made of stones filled with the circle-like
foram tests. They are easy to see since they are
about as big as a dime.
When examined under a microscope, the
foram’s chromatids can be seen. The nuclear
membrane disappears and the chromosomes
line up in the center of the cell. The foram
then goes through the rest of the stages of
mitosis: metaphase, anaphase, and telophase.
Finally, the cytoplasm divides and there are
two forams with the same genetic material.
The new cell has the exact same genetic information as the parent cell. It then uses fluids
from its skin to make a shell that looks just
like its parent. It feeds on the same food and
will, eventually, go through mitosis and cell
division itself.
When it comes time for a foram to reproduce the most common way they do it is by
mitosis. The cell slips outside its test and the
nucleus begins to enter prophase. This is a
dangerous time for the foram because its
energy is going into mitosis and it cannot
swim away from predators.
1. Are all eukaryotic cells found in large animals?
2. What are forams related to?
3. How are the forams different from their relative?
4. How big are the forams found in the stones of the Egyptian pyramids?
5. How does a foram reproduce itself?
6. Will the offspring be different from the parent? Explain.
28 Cell Reproduction
Copyright © Glencoe/McGraw-Hill, a division of the McGraw-Hill Companies, Inc.
1
Date
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Name
2
Date
Enrichment
Class
Crossing Over
When pairs of chromosomes come together during meiosis I, they trade some genetic material.
The trading of genetic material between chromosomes is called crossing over. This is one reason
sexual reproduction results in so much genetic variability. For example, brothers and sisters can
have different hair color.
Meeting Individual Needs
Here is a summary of how crossing over occurs:
1. Chromosome pairs line up side by side during early prophase I. At
this stage, each chromosome is made up of two identical strands
held together at the centromere.
2. The pairs of double-stranded chromosomes twist around each
other. Breaks in the strands of each chromosome reattach to
strands from the paired chromosome. The point where crossing
over occurs is visible as an X-shaped structure.
3. Spindle fibers attach to one side of each centromere during
metaphase I. As the chromosomes are pulled apart during anaphase
I, the points where the chromosomes cross over separate. Each chromosome takes a small piece of new genetic material with it.
In the following activity, you will demonstrate crossing over by
making a clay model of chromosomes.
Copyright © Glencoe/McGraw-Hill, a division of the McGraw-Hill Companies, Inc.
Materials
red and blue plasticine
WARNING: Do not taste, eat or drink any materials used in this activity.
Procedure
1. Each chromosome is made of two identical strands held together by a centromere. The
centromere can be shown as a ball of plasticine. Make one chromosome using red plasticine.
2. Make another chromosome using blue plasticine.
3. Show different ways crossing over can occur. Show how double crossovers occur.
Conclude and Apply
How does crossing over explain genetic variability?
Cell Reproduction
29
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Name
Enrichment
Class
Radiation, Genes,
and Mutations
Meeting Individual Needs
Radiation is known to be dangerous to
human bodies. Millions of body cells exposed
to high-energy waves from X rays, radon gas,
and ultra-violet radiation have been permanently harmed by these emissions. The DNA of
the individual cells is too delicate to withstand
the energy produced by these kinds of radiation. The DNA molecules are torn apart or
suffer drastic changes in their genetic sequencing which can lead to mutations.
Under normal conditions, DNA molecules
routinely undergo some sort of genetic alteration. During replication, or copying of the
cell, mistakes in gene sequencing often occur.
However, the cell contains many repair mechanisms that continually monitor and repair
damage to DNA strands.
Radiation and Gene Damage
When cells are exposed to radiation, however, several types of molecular destruction
are possible. The DNA is both physically and
chemically broken (cleaved) by the high
energy waves. Often the repair of the DNA
strand by enzymes or other chemicals is not
adequate enough to put the DNA molecule
back together in its proper sequence.
When replication occurs, the new strands of
DNA carry the new altered sequence of genes.
As each generation of cells is produced
the mutations continue to show up in the
replicated cells. These cells are often nonfunctional and become tumorous growths
such as skin cancer.
Radon
Radon gas is especially harmful to lung tissues because it enters the body through regular breathing in a building contaminated with
radon. The emissions easily damage fragile
lung tissues. Not only do the high-energy
radioactive emissions destroy cellular DNA,
but other large particles tear the cell membranes apart leaving the body strained to constantly repair the damaged tissues.
Fortunately, many forms of genetic alteration by radiation are preventable. Limiting
exposure to X rays, using sunscreen, and testing buildings for radon levels can help prevent
damage to a cell’s genetic makeup.
1. What makes radiation dangerous to cells?
2. How are skin cells damaged by exposure to ultra-violet radiation?
3. In what two ways does radon destroy genetic information in lung tissue cells?
4. Why do you think it’s important that a pregnant woman always tell her healthcare provider she
is pregnant before receiving any X ray examination?
30 Cell Reproduction
Copyright © Glencoe/McGraw-Hill, a division of the McGraw-Hill Companies, Inc.
3
Date
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Name
Date
Note-taking
Worksheet
Section 1
Class
Cell Reproduction
Cell Division and Mitosis
A. Cell division—increases the number of cells and causes many-celled _____________ to grow
B. The Cell Cycle—series of events that takes place from one _____________ to the next
1. Cells have periods of formation, growth and development, and death called _______________.
period of __________ and _______________.
a. During interphase, a cell duplicates its _______________ and prepares for cell division.
b. After interphase, the nucleus divides, and then the ______________ separates to form
two new cells.
C. Mitosis—process in which the nucleus divides to form two identical __________
1. Chromosome—structure in the nucleus that contains ______________ material
2. Prophase
a. Nucleolus and ____________________ disintegrate.
b. __________ move to opposite ends of the cell.
Copyright © Glencoe/McGraw-Hill, a division of the McGraw-Hill Companies, Inc.
c. ______________ begin to stretch across the cell.
3. Metaphase—pairs of ______________ line up across the center of the cell.
4. Anaphase
a. Each ______________ divides.
b. Each pair of chromatids _____________ and moves to opposite ends of the cell.
5. _________—spindle fibers disappear and a new nucleus forms.
D. Division of the Cytoplasm—for most cells, the _____________ separates after the nucleus
divides.
1. In ______________ cells, the cell membrane pinches in the middle and the cytoplasm
divides.
2. In ______________ cells, a cell plate forms.
E. Results of mitosis
1. Each cell in your body, except sex cells, has a nucleus with ______ chromosomes.
2. Allows growth and ____________ worn out or damaged cells
Cell Reproduction
31
Meeting Individual Needs
2. Interphase—most of the life of any eukaryotic cell, or cell with a nucleus, is spent in a
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Name
Date
Class
Note-taking Worksheet (continued)
F. ____________________—a new organism is produced from one parent organism.
1. An organism with no nucleus divides into two identical organisms by ___________.
2. _______—a small, exact copy of the adult grows from the body of the parent.
3. In ________________, a whole new organism grows from each piece of the parent.
Section 2
Sexual Reproduction and Meiosis
A. ______ reproduction—two sex cells, usually an egg and a sperm, come together.
a. Sperm are formed in the ________ reproductive organs.
b. Eggs are formed in the __________ reproductive organs.
c. A cell that forms from fertilization is a __________.
2. Following fertilization, ___________ begins and a new organism develops.
3. Human body cells are ___________, because they have 23 pairs of similar chromosomes.
4. Human sex cells are ___________, because they have 23 single chromosomes.
B. _______—a process that produces haploid sex cells and ensures that offspring have the same
___________ number as its parent.
1. In meiosis I, the nucleus divides and produces two new cells with one duplicated
______________ each.
2. In meiosis II, the nuclei divide and the chromatids separate, producing ________ cells with
half the number of chromosomes of the original nucleus.
Section 3
DNA
A. DNA—a ____________ that contains information that an organism needs to grow and function
1. Watson and _________ made an accurate model of DNA in 1953.
2. The structure of DNA is similar to a __________________.
a. The sides of the ladder are made up of _____________________________.
b. The rungs of the ladder are made up of __________________.
3. Before a cell divides, its DNA duplicates itself by unwinding and separating its sides, then
each side becomes a pattern on which a _____________ forms.
32 Cell Reproduction
Copyright © Glencoe/McGraw-Hill, a division of the McGraw-Hill Companies, Inc.
Meeting Individual Needs
1. Fertilization—the joining of an _______ and a _________, generally from two different
organisms of the same species
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Note-taking Worksheet (continued)
B. Genes—sections of _______ on a chromosome
1. Contain instructions for making specific ____________
2. RNA carries the _________ for making proteins from the nucleus to the ribosomes in the
cytoplasm.
a. Messenger RNA carries the code that directs the order in which the _______________
bond.
c. ________ RNA brings amino acids to the ribosomes to build the protein.
3. Cells use only the _________ that direct the making of proteins needed by that cell.
C. Mutations—any permanent __________ in the DNA sequence of a cell’s gene or chromosome
1. Can be caused by outside factors like X rays, ____________, and some chemicals
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2. A change in a gene or chromosome can change the __________ of an organism.
Cell Reproduction
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Meeting Individual Needs
b. Ribosomal RNA makes up _____________, where proteins are built.