Download Chapter 2 Resource: Traits and How They Change

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Glencoe Science
Chapter Resources
Traits and
How They Change
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
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
Traits and How They Change program. Any other reproduction, for use or sale, is
prohibited without prior written permission of the publisher.
Send all inquiries to:
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ISBN 0-07-867146-9
Printed in the United States of America.
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Reproducible
Student Pages
Reproducible Student Pages
■
Hands-On Activities
MiniLAB: Try at Home Observing Gravity and Stem Growth . . . . . . . 3
MiniLAB: Observing Fruit Fly Phenotypes . . . . . . . . . . . . . . . . . . . . . . 4
Lab: Jelly Bean Hunt . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5
Lab: Toothpick Fish . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7
Laboratory Activity 1: Identifying Bean Traits . . . . . . . . . . . . . . . . . . . 9
Laboratory Activity 2: How many plants can a pepper produce? . . . . 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
Traits and How They Change
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Hands-On Activities
Hands-On
Activities
2 Traits and How They Change
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Date
Class
Hands-On Activities
Name
Observing Gravity and Stem Growth
Procedure
1. Plant popcorn or other seeds in a pot of soil.
2. Water thoroughly.
3. When the plants begin to sprout, turn the pot on its side for three days. You
may turn the pot upright to water the plant but return it to the same position
each time.
Analysis
1. Predict what eventually would happen if you rolled the pot so that the stems were growing
downward.
Copyright © Glencoe/McGraw-Hill, a division of the McGraw-Hill Companies, Inc.
2. Does gravity affect phenotype? Explain.
Traits and How They Change
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Name
Date
Class
Procedure
1. Obtain a container of fruit flies from your teacher.
2. Use a magnifying lens to observe the eyes and wings of the flies.
Data and Observations
Fruit Fly Phenotypes
Eyes
Wings
Your
Observations
Analysis
1. What variations did you find in the eyes and wings of the flies?
2. Hypothesize what caused the variations.
4 Traits and How They Change
Copyright © Glencoe/McGraw-Hill, a division of the McGraw-Hill Companies, Inc.
Hands-On Activities
Observing Fruit Fly Phenotypes
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Name
Date
Class
Hands-On Activities
Jelly Bean Hunt
Lab Preview
Directions: Answer these questions before you begin the LAB.
1. What do the jelly beans and the poster board represent?
2. Why should you not eat or drink anything in the laboratory?
The environment plays an important role in the development of some
phenotypes. In this lab, you will observe how camouflaged animals are less
likely to be captured by predators.
Real-World Question
Procedure
How do differences in animal coloration camouflage some but expose others to predation?
1. Determine which shade is which number.
2. Put the poster board on the desk. Have your
partner turn his or her back to the poster.
3. Arrange the 50 jelly beans on the poster.
Mix up the different shades of jelly beans.
4. Have your partner, who is the hunter, turn
and pick up one at a time, as many jelly
beans as possible in 3 s.
5. Count the number of each shade of jelly
bean the hunter caught. Record these
numbers in the Hunt #1 row in the table
in the Data and Observations section.
6. Mix up the jelly beans and have the hunter
make four more hunts.
Copyright © Glencoe/McGraw-Hill, a division of the McGraw-Hill Companies, Inc.
Materials
five shades of green jelly beans (10 each)
*five shades of another color (10 each)
green poster board
*poster board that matches chosen color
*Alternative materials
Goals
■
■
Model camouflage and predation.
Infer how the effect of the environment on
phenotype helps some animals survive.
Safety Precautions
WARNING: Never eat or drink anything in the
lab.
Traits and How They Change
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Name
Date
Class
(continued)
Jelly Bean Data
Shade #1
Shade #2
Shade #3
Shade #4
Shade #5
Hunt #1
Hunt #2
Hunt #3
Hunt #4
Hunt #5
Conclude and Apply
1. Observe Which shade of jelly bean did the hunter select most often? Least often?
2. Explain why the hunter caught more of certain shades of green jelly beans than others.
3. Predict your results with a different shade of poster board.
4. Infer how your experiment could explain the specific green color of tropical lizards.
Communicating Your Data
Describe how the environment’s effect on some phenotypes can help animals survive.
For more help, refer to the Science Skill Handbook.
6 Traits and How They Change
Copyright © Glencoe/McGraw-Hill, a division of the McGraw-Hill Companies, Inc.
Hands-On Activities
Data and Observations
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Name
Date
Class
Hands-On Activities
Toothpick Fish
Lab Preview
Directions: Answer these questions before you begin the Lab.
1. What safety precautions are necessary with this lab?
2. What do the colored toothpicks represent?
The genotypes and phenotypes in a population can be affected by environmental changes. In this lab, you will simulate how the environment can
affect the genetics and population of a species.
Real-World Question
How can the environment affect a species’
gene pool?
Goals
Copyright © Glencoe/McGraw-Hill, a division of the McGraw-Hill Companies, Inc.
■
■
■
Identify how the environment can affect a
gene pool.
Demonstrate how the law of independent
assortment is random.
Distinguish between the number of phenotypes and genotypes.
Materials
petri dish
toothpicks (24) (8 green, 8 red, 8 yellow)
Safety Precautions
Procedure
1. The petri dish represents a fish gene pool
and the colored toothpicks represent the
alleles that control fish skin color. The
green allele is dominant. The red and yellow alleles are recessive to green, but fish
with a red allele and a yellow allele have
orange skin. List all of the genotypes for
the four fish skin colors on a separate piece
of paper.
2. Make a copy of Table A and Table B from
your textbook on a separate sheet of paper.
3. Select an allele pair (2 toothpicks) without
looking and record the results in Table A.
Continue selecting and recording pairs
until the gene pool is empty. Do not mix
up the pairs.
4. Count and record in Table B the numbers
of each color of fish offspring in the first
generation.
5. Predators easily spot yellow fish in the
green seaweed. Remove the yellow fish and
put the remaining alleles back in the gene
pool. Select a second generation of fish
without looking. Record your results in
Table A. Repeat step 3.
6. Remove yellow fish again and return the
surviving fish alleles to the petri dish.
Repeat step 4 two more times to model the
third generation and fourth generation.
7. Draw a fifth generation from the gene
pool. Record the data in Table A.
8. Factory wastes are dumped into the
stream and kill the seaweed. The green
fish now are easily seen by predators.
Remove the green fish and record the
number of surviving offspring in the last
row of Table B.
Traits and How They Change
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Name
Date
Class
(continued)
Allele Pairs and Fish Offspring Skin Colors
Generations
First
Allele
pair
Skin
color
Second
Allele
pair
Skin
color
Third
Allele
pair
Skin
color
Fourth
Allele
pair
Skin
color
Fifth
Allele
pair
Skin
color
Analyze Your Data
1. Compare the population in the fourth generation to the first, second, and third generation.
Explain any differences.
2. Determine if any alleles have disappeared. Describe why it did or did not occur.
Conclude and Apply
1. Explain how the environment affected the fish population.
2. Infer how the environmental changes could lead to the extinction of a species.
Communicating Your Data
Combine the data in Table A from all students in your class. Calculate the average number
of each fish color for each generation. How do your data compare to the class average?
8 Traits and How They Change
Copyright © Glencoe/McGraw-Hill, a division of the McGraw-Hill Companies, Inc.
Hands-On Activities
Table A
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Date
1
Laboratory
Activity
Class
Identifying Bean Traits
You have learned that every living thing has certain inherited traits. It is often easy to recognize the
physical traits of animals—cats with striped coats or solid coats; dogs with floppy ears or short ears.
But plants also have traits that are recognizable. How can you classify plants according to their traits?
Strategy
You will identify the physical traits of beans.
You will classify a bag of mixed beans into two
main groups and four sub-groups based on
the presence or absence of physical traits.
Materials
small bag of mixed beans
large plastic container
medium plastic containers(2)
small plastic containers(4)
Procedure
1. Empty your bag of beans into the large
plastic container.
2. Examine your beans closely. Make a list of
the physical traits of your beans. Traits
define color, shape, and other distinctive
features of the beans.
3. Of the traits you observe, choose one trait
that allows you to divide your beans into
two groups—Group 1 and Group 2.
4. Divide the beans into Groups 1 and 2
according to the trait you chose in step 3.
Use the two medium containers to hold the
beans in Groups 1 and 2.
5. Examine Groups 1 and 2 closely. Choose a
trait that will allow you to divide Group 1
into two sub-groups—Groups 1a and 1b.
Then choose a trait that allows you to
divide Group 2 into two sub-groups—
Groups 2a and 2b.
6. Divide the beans according to the traits
you chose in step 5. Use the four small
containers to hold the beans in the four
sub-groups.
Copyright © Glencoe/McGraw-Hill, a division of the McGraw-Hill Companies, Inc.
Data and Observations
In the diagram below, fill in the traits you used to classify your beans.
Group 1
Group 2
Trait: _______________________
Trait: _______________________
Group 2a
Group 1a
Trait: ____________
Trait: ____________
Group 1b
Trait: ____________
Group 2b
Trait: ____________
Traits and How They Change
9
Hands-On Activities
Name
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Name
Date
Class
Laboratory Activity 1 (continued)
1. What trait did you use to divide the entire bag of beans into two groups? Explain your reasons
for choosing this trait over another.
2. What traits did you choose to divide the two groups of beans into four sub-groups? Was
making the four sub-groups easier or more difficult than making the first two groups of beans?
Why?
3. How many different kinds of beans were there in your original bag of beans? Why do you think
there are so many different kinds of beans?
Strategy Check
Can you identify the physical traits of beans?
Can you classify beans into two groups and four sub-groups according to specific traits?
10 Traits and How They Change
Copyright © Glencoe/McGraw-Hill, a division of the McGraw-Hill Companies, Inc.
Hands-On Activities
Questions and Conclusions
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Date
2
Laboratory
Activity
Class
How many plants can a pepper
produce?
You have learned that environmental factors influence how many organisms survive in an area.
These factors can be either living or nonliving. Most organisms overproduce, meaning that, for
example, if one plant produced 1,000 seeds and each seed grew into a new plant the next year, 1,000
new plants would result. If each of these 1,000 new plants produced 1,000 seeds, then a total of
1,000,000 plants would result. Environmental factors help prevent such large numbers from growing.
Strategy
You will count the number of seeds in one green pepper.
You will calculate the average number of green pepper seeds in the class.
You will determine how many plants would grow from these green pepper seeds over a
five year period.
Safety Precautions
Materials
green pepper (with seeds), cut in half
Copyright © Glencoe/McGraw-Hill, a division of the McGraw-Hill Companies, Inc.
Procedure
1. Remove the seeds from the pepper and
count them. Record the number in Table 1
in the Data and Observations section.
2. Collect seed totals from the rest of the class
to calculate the average number of seeds in
a green pepper. Add the seed totals, then
divide by the number of people in the
class. Round the average off to the nearest
hundred. Record the numbers in Table 1.
3. Complete the data table using the following
assumptions:
a. One green pepper plant grew in the
first year.
b. The first green pepper plant produced the
rounded-off average number of seeds.
c. All seeds produced by the green pepper
plant grow into new plants.
d. Every new plant always produces the
rounded-off number of seeds each year.
4. Determine how many new green pepper
plants will grow in the second year. Record
this number in Table 2.
5. Determine how many new green pepper
plants will grow in the third, fourth, and
fifth years. Record these numbers in Table 2.
Data and Observations
Table 1
Seeds in green pepper
Seeds in all green peppers
Number of students in a class
Average number of green pepper seeds
Class average rounded to nearest 100
Traits and How They Change
11
Hands-On Activities
Name
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Name
Date
Class
Laboratory Activity 2 (continued)
Year
Number of pepper plants
1
2
3
4
5
Questions and Conclusions
1. How many green pepper plants were recorded for the first year? How many plants will be
produced in the fifth year?
2. Name some of the living and nonliving factors in the environment that would prevent every
green pepper seed from growing into a new plant.
3. What are the chances that 100,000,000 green pepper plants will eventually result from the seeds
of one green pepper plant? Explain your answer.
4. How is it adaptive for organisms to overproduce?
12 Traits and How They Change
Copyright © Glencoe/McGraw-Hill, a division of the McGraw-Hill Companies, Inc.
Hands-On Activities
Table 2
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Name
Date
Class
Hands-On Activities
Laboratory Activity 2 (continued)
5. What other factors have you learned about that help ensure the survival of a species?
Strategy Check
Can you determine the number of seeds in one green pepper?
Can you calculate the average number of seeds per pepper for your class?
Copyright © Glencoe/McGraw-Hill, a division of the McGraw-Hill Companies, Inc.
Can you determine how many plants will grow from one green pepper each year for
five years?
Traits and How They Change
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Name
Date
Class
Hands-On Activities
Traits and How They Change
Directions: Use this page to label your Foldable at the beginning of the chapter.
blood type
eye color
hair color
height
Copyright © Glencoe/McGraw-Hill, a division of the McGraw-Hill Companies, Inc.
ear shape
Traits and How They Change
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Meeting Individual Needs
Meeting Individual
Needs
16 Traits and How They Change
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Name
Date
Directed Reading for
Content Mastery
Class
Overview
Traits and How They Change
Directions: Complete the concept map using the terms listed below.
natural selection
alleles
evolution
phenotype
DNA
genes
mutation
An organism’s
Meeting Individual Needs
1.
is determined by its
genotype
environment
which is coded in
which, over time, can influence
an organism through
2.
Copyright © Glencoe/McGraw-Hill, a division of the McGraw-Hill Companies, Inc.
5.
located in
and
3.
6.
of which there are
different forms called
and
4.
7.
Traits and How They Change
17
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Name
Date
Section 1
Directed Reading for
Content Mastery
■
Class
Traits and the
Environment
Directions: Use the clues below to complete the crossword puzzle.
1
3
4
I
E
6
T
7
8
D
I
P
L
Across
3. Traits passed from parents
6. Portion of the DNA in your chromosomes
7. The visible traits of an organism
8. Type of environmental factor, such as the presence of a hormone, that might
affect an organism’s phenotype
Down
1. A complex material that contains all the information needed to create an organism
2. An organism’s genetic makeup
4. Type of environmental factor, such as temperature or amount of light, that might
affect an organism’s phenotype
5. Feature passed from parents to offspring
18 Traits and How They Change
Copyright © Glencoe/McGraw-Hill, a division of the McGraw-Hill Companies, Inc.
Meeting Individual Needs
5
2
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Name
Date
Directed Reading for
Content Mastery
Section 2
Section 3
Class
■
■
Genetics
Environmental
Impact over Time
Directions: For each of the following, write the letter of the term or phrase that best completes the sentence.
2. Each parent passing only one of the alleles to its offspring is known as
______.
a. segregation
b. dominance
3. The theory of ______ helps to explain the wide variety of living things.
a. dominance
b. evolution
4. The law of ______ states that the alleles for one trait have no effect on
how alleles for another trait are inherited.
a. segregation
b. independent assortment
Copyright © Glencoe/McGraw-Hill, a division of the McGraw-Hill Companies, Inc.
5. A gene has two alleles, A and a. If a parent with a genotype of AA is
crossed with a parent with a genotype of aa, the offspring will have a
genotype of ______.
a. Aa
b. AA
Directions: Read the information below. Then in the Punnett square, write the correct genotype. On the line
next to the square, write the correct phenotype.
6. One trait in pea plants is the color of their pea pods. The gene for the trait has
two alleles. The green allele (G) is dominant, and the yellow allele is recessive (g).
The Punnett square shows a cross between two parents each with a dominant
allele and recessive allele. Filling in the Punnett square will show you what traits
their offspring will have.
Parent
alleles
green pea pods
________________________
G
b. ________________________
g
G
GG
b.
g
a.
a. ________________________
c.
c. ________________________
Traits and How They Change
19
Meeting Individual Needs
1. Destruction of a species’ habitat is one cause of ______.
a. extinction
b. mutation
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Name
Date
Directed Reading for
Content Mastery
Class
Key Terms
Traits and How They Change
Directions: Match the terms in Column II with the definitions in Column I. Write the letter of the correct term in
the blank at the left.
Column I
Column II
1. different forms of a gene
a. adaptive radiation
Meeting Individual Needs
3. organisms well-adapted to their environment
survive and reproduce at a greater rate than
other organisms do
b. gene
c. allele
4. the science of how traits are passed from
parents to offspring
d. extinction
5. occurs when the last individual of a species dies
e. genetics
6. several species are produced from one
ancestral species
f. natural selection
7. an organism’s observable traits that result from
both its genetic makeup and its environment
g. genotype
8. part of the DNA code on a chromosome
h. phenotype
Directions: Complete the following sentences using the terms listed below.
dominant
evolution
mutation
recessive
trait
9. A feature that an organism inherits is called a(n) ____________________.
10. ____________________ is the process in which DNA changes to form new
alleles.
11. ____________________ is the change in the genetic makeup of a species over
time.
12. ____________________ alleles always have an effect on an organism’s phenotype.
13. ____________________ alleles affect an organism’s phenotype only when two
are present in the genotype.
20 Traits and How They Change
Copyright © Glencoe/McGraw-Hill, a division of the McGraw-Hill Companies, Inc.
2. an organism’s genetic makeup
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Nombre
Fecha
Lectura dirigida para
Dominio del contenido
Clase
Sinopsis
Los rasgos y cómo cambian
Instrucciones: Completa el mapa conceptual usando los siguientes términos.
selección natural
alelos
evolución
fenotipo
DNA
genes
mutación
Satisface las necesidades individuales
El
1.
de un organismo lo determina su
genotipo
que está codificado en
ambiente
el cual, con el paso del tiempo,
influye sobre
2.
Copyright © Glencoe/McGraw-Hill, a division of the McGraw-Hill Companies, Inc.
5.
ubicados en
y
3.
6.
de los cuales hay dos formas diferentes llamadas
y
4.
7.
Los rasgos y cómo cambian
21
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Nombre
Fecha
Sección 1
Lectura dirigida para
Dominio del contenido
Clase
■
Los rasgos y el
ambiente
Instrucciones: Usa las claves para completar el crucigrama.
1
2
3
I
4
G
6
7
8
Horizontales
2. Rasgos visibles de un organismo
5. Tipo de factor ambiental, como la temperatura o la cantidad de luz, que puede
afectar el fenotipo de un organismo
6. Características transmitidas de progenitores a progenie
7. Se dice de los rasgos transmitidos por los progenitores
Verticales
2. Composición genética de un organismo
3. Tipo de factor ambiental, como la presencia de una hormona, que puede afectar
el fenotipo de un organismo
4. Porción de ADN de los cromosomas
8. Material complejo que contiene toda la información necesaria para crear un nuevo
organismo
22 Los rasgos y cómo cambian
Copyright © Glencoe/McGraw-Hill, a division of the McGraw-Hill Companies, Inc.
Satisface las necesidades individuales
5
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Nombre
Fecha
Lectura dirigida para
Dominio del contenido
Sección 2
Sección 3
Clase
■
■
La genética
Impacto ambiental a través del tiempo
2. “ Cada progenitor pasa solamente uno de los alelos a su progenie”, esto
se conoce como ______.
a. segregación
b. dominancia
3. La teoría de la ______ ayuda a explicar la gran variedad de organismos
vivos.
a. dominancia
b. evolución
4. La ley de la ______ establece que, en la herencia, los alelos para un rasgo
no afectan los alelos de otro rasgo.
a. segregación
b. segregación independiente
Copyright © Glencoe/McGraw-Hill, a division of the McGraw-Hill Companies, Inc.
5. Un gene tiene dos alelos, A y a. Si un progenitor de genotipo AA se
cruza con un progenitor de genotipo aa, la progenie tendrá el
genotipo ______.
a. Aa
b. AA
Instrucciones: Lee la información. Llena luego el cuadrado de Punnett. Escribe al lado de las letras los pares de
alelos de la progenie y el rasgo que recibirán.
6. Un rasgo de las plantas de guisantes es el color de la vaina. El gene para este rasgo
tiene dos alelos. El alelo verde (G) es dominante y el alelo amarillo es recesivo(g).
El cuadrado de Punnett muestra un cruce entre dos progenitores que tienen cada
uno un alelo dominante y uno recesivo. Llena el cuadrado para mostrar los rasgos que tendrá la progenie.
Los alelos
del progenitor
vainas verdes
________________________
G
b. ________________________
g
G
GG
b.
g
a.
a. ________________________
c.
c. ________________________
Los ragos y cómo cambian
23
Satisface las necesidades individuales
Instrucciones: Escribe la letra del término o frase que complete mejor cada una de las oraciones.
1. La destrucción del hábitat de una especie es una causa de ______.
a. extinción
b. mutación
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Nombre
Fecha
Lectura dirigida para
Dominio del contenido
Clase
Términos claves
Los rasgos y cómo cambian
Instrucciones: Coordina los términos de la Columna II con las definiciones de la Columna I. Escribe la letra del
término correcto en el espacio en blanco a la izquierda.
Columna I
Columna II
1. diferentes formas de un gene
a. radiación adaptativa
3. los organismos bien adaptados a su ambiente
sobreviven y se reproducen a tasas más altas que
otros organismos
4. estudio de cómo se pasan los rasgos de
progenitores a progenie
b. gene
c. alelo
d. extinción
5. cuando muere el último individuo de una especie
6. se producen varias especies a partir de especies
ancestrales
7. rasgos observables de un organismo que resultan
de su composición genética y de su ambiente
e. genética
f. selección natural
g. genotipo
8. parte del código del ADN en un cromosoma
h. fenotipo
Instrucciones: Completa las oraciones con los siguientes términos.
dominante
evolución
mutación
recesivo
rasgo
9. Una característica heredada se llama también ____________________.
10. El(La) ____________________ es el proceso mediante el cual el ADN cambia y
forma alelos nuevos.
11. El(La) ____________________ es el cambio en la composición genética de
una especie a través del tiempo.
12. Los alelos ____________________ siempre afectan el fenotipo de los
organismos.
13. Los alelos ____________________ afectan el fenotipo de un organismo
solamente cuando hay dos de ellos presentes en el genotipo.
24 Los rasgos y cómo cambian
Copyright © Glencoe/McGraw-Hill, a division of the McGraw-Hill Companies, Inc.
Satisface las necesidades individuales
2. composición genética de un organismo
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Name
Date
1
Reinforcement
Class
Traits and the Environment
Directions: In number 1 below, a code letter has been substituted for each letter of the alphabet. To find out
what the sentence says, use the following key to decode it. In the key, the code letters are shown directly below the
alphabet letters that they stand for. Write the correct letter above each code letter, then read the sentence aloud.
A B C D E F G H I J K L M N O P Q R S T U V W X Y Z
Z Y X W V U T S R Q P O N M L K J I H G F E D C B A
__________
XVO O H
__________
X LW V W
____
RM
_______
GSZG
_______
SZEV
___
Z
_______
WMZ
__________
ULFMW
_____________,
MFXOVFH
_____
RM
__________
GIZRGH
_____
ZIV
Meeting Individual Needs
1. ____
RM
___________________.
XSILNLHLNVH
Sentence:
Copyright © Glencoe/McGraw-Hill, a division of the McGraw-Hill Companies, Inc.
Directions: Complete the following sentences using the correct terms.
2. An organism’s genetic makeup is called its _______________________. The combination of
genetic makeup and environment produce observable traits called _______________________.
3. According to Darwin and Wallace, changes happen from generation to generation that result in
adaptations to the environment. This process is called _______________________.
Darwin and Wallace proposed that organisms that are better adapted to their environment
survive and reproduce at a greater rate than other organisms that are not. They called
this _______________________.
Directions: Match the environmental effects in Column II with their classification in Column I. Write the letter of
the correct environmental effect in the blank at the left.
Column I
Column II
4. external effect
a. hormones
5. internal effect
b. sunlight
6. competition
c. limited supply of growth factors
Traits and How They Change
25
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Name
2
Date
Class
Genetics
Reinforcement
Directions: Use the clues below to complete the crossword puzzle.
1
2
3
4
6
7
8
9
10
11
Across
Down
1. Mendel’s plants
2. Chart to help predict genetic crosses
4. Passing of traits from parent to offspring
3. Science of heredity
5. Famous heredity scientist
7. Parents produce ______.
6. Alleles that will show their effect on the
phenotype when present in the genotype
8. Different form of a gene
9. Parts of the DNA code on chromosomes
10. Two of the same alleles of this type are
needed to produce a trait
11. Principle that each parent passes only one
allele for a trait to its offspring
26 Traits and How They Change
Copyright © Glencoe/McGraw-Hill, a division of the McGraw-Hill Companies, Inc.
Meeting Individual Needs
5
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Name
3
Date
Reinforcement
Class
Environmental Impact
over Time
Directions: Find the mistakes in the statements below. Rewrite each statement correctly on the lines provided.
1. Pollution is a living environmental factor that can limit whether a species survives in a habitat.
3. In Darwin’s theory, the theory of evolution by independent assortment, several factors act
together over time to make new species.
4. Over generations, groups in an environment adapt to predators by evolving ways to be detected.
Copyright © Glencoe/McGraw-Hill, a division of the McGraw-Hill Companies, Inc.
5. Darwin and Mendel were working separately to determine theories of evolution.
6. Mapping is the process that changes DNA to form new alleles.
7. Selective breeding is used in nature to provide change over time.
8. The production of several species from many ancestral species is called adaptive radiation.
9. Evidence of selective breeding is found in fossil records.
10. New species can occur when natural selection favors a useless variation.
Traits and How They Change
27
Meeting Individual Needs
2. Predators never limit the number of animals found in an environment.
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Name
Enrichment
Class
Genes and Environmental
Factors
Meeting Individual Needs
Biological research has made great advances
related to human genes and their functions.
Included among these discoveries are genes
related to a variety of types of cancers. Breast,
colon, and prostate cancer are three types of
cancer now associated with particular genes.
A common misunderstanding, however, is
that these genes are responsible for causing
cancer. While genes may have an influence on
a person’s chance of developing cancer, other
factors, especially the environment, are as
responsible as genetics for producing cancer.
Breast Cancer Connection?
Breast cancer is a major health threat for
women. This type of cancer can affect women
of all ages and backgrounds. Two genes have
been connected to breast cancer, BRCA-1 and
BRCA-2. Women with both of these genes
have a 70% to 85% chance of developing
breast cancer. However, only 2% of women
have both genes. This means that most breast
cancer patients may not have either of the
genes responsible for causing breast cancer.
Scientists have discovered other genes that
might increase a person’s risk of developing
cancer depending on their environment.
Many genes, disease-causing or not, come in
several different versions. These genes are
called polymorphic, or many shapes. Some
versions of certain genes, when exposed to
certain environmental factors, increase a
person’s risk for developing a type of cancer.
For example, the NAT gene has a relationship
with cigarette smoke and breast cancer.
The NAT Gene
The NAT gene’s function is to rid a body’s
cells of a particular toxin found in cigarette
smoke. There are two versions of the NAT gene,
one that works quickly and one that works
slowly. If a person has the slow version and
their environment includes cigarette smoke,
their risk of contracting breast cancer is higher.
Experts believe that this type of situation,
where genes and the environment work
together, is much more common than we
know. Before people can expect a precise test
to determine their risk of cancer, more work
needs to be done. However, it is clear that
some forms of cancer can be avoided by
controlling your environment.
1. List several types of cancer that have a specific genetic component.
2. Who would be at a greater risk of developing breast cancer, a person with a family history of
BRCA-1 or a person with a family history of the slow NAT gene? Why?
3. List and discuss several possible benefits as well as several problems with genetic testing for
cancer genes.
28 Traits and How They Change
Copyright © Glencoe/McGraw-Hill, a division of the McGraw-Hill Companies, Inc.
1
Date
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Name
Enrichment
Genes and Disease
When you look in the mirror you probably
see some physical characteristics that are similar
to your mother and some that are similar to
your father. Phenotypically and genotypically,
people are combinations of their parents. While
nobody can guarantee what a child will look
like, our understanding of genetics allows us to
predict, with some confidence, the probability
of a child having a particular trait. When
discussing the similarities between parents
and children, people often focus on external
traits such as eye color, skin pigment, and hair
color. There are other traits, less obvious to the
naked eye, that children can inherit from their
parents that might affect their lives more significantly than eye color.
Genetic Diseases
Copyright © Glencoe/McGraw-Hill, a division of the McGraw-Hill Companies, Inc.
Class
Scientists have identified several genes that are
responsible for, or contribute to, specific diseases.
Diseases that are passed from parents to children
through their genes include some types of breast
cancer, Alzheimer’s disease, and Huntington’s
disease. With advances in DNA technology and
genetics, it is now possible for people to be tested
to determine if they have the gene related to a
specific disease. Currently, experts do not recommend everyone have a genetic screening, only
those at high risk or with a family history of a
disease. Some might want this information to
make informed decisions about having children,
or to have preventative care to reduce their risk
of contracting the disease.
The number of diseases that are influenced
by single genes is small. It is more common to
see several genes, or genes in combination
with the environment, influence a person’s
susceptibility to a disease.
Disease Severity
Scientists are now finding that groups of
genes, while not directly linked to a single
disease, might play a role in the severity of the
disease. This can be seen in some children with
bronchitis. While thousands of children are
exposed to the virus that can lead to bronchitis,
most children only get the sniffles. Children
with a specific gene may become seriously ill
and require hospitalization and oxygen therapy.
Similarly, in areas of the world where malaria
is common, not all people become extremely ill.
Scientists now believe a person’s genes dictate
the severity of the symptoms. It appears that the
genes in question may play a role in immune
response and the ability of a person to fight off
disease causing organisms.
More Information to Come
As scientists discover the location and
function of more genes, they will provide us
with more information about the role a
person’s genes play in their health. If people
choose to be tested to determine their genetic
makeup, they and their doctor can use this
information to make decisions about their life
or effective treatments.
1. If a person tested has a “disease gene,” will that person necessarily become sick? Explain.
2. Describe some of the reasons a person might want to know what genes he or she has.
3. Why might a person want to be tested for genes related to the immune system?
Traits and How They Change
29
Meeting Individual Needs
2
Date
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Name
Enrichment
Class
Confrontational Squirrels
Meeting Individual Needs
You’re hiking along a trail when suddenly
you hear a distinctive rattling sound. You
freeze and see in front of you a rattlesnake
shaking its tail and looking dangerous. If you
are like most people, you hope that the snake
decides to go on its way and leave you alone.
Ground squirrels, however, have a different
reaction. They might confront the snake,
lunging, kicking dirt at the snake, and even
partially burying it. Why such aggressive
behavior from such a little animal?
No Fear
Ground squirrels show no fear when confronting rattlesnakes. Squirrels will taunt the
snake. If the snake does strike, the squirrel will
leap evasively backwards to avoid the venomous
fangs. Sometimes, even though squirrels are
fast, the snake hits its target, and is able to inject
venom into the squirrel. This often has no
effect. Many ground squirrels found in areas
where rattlesnakes also exist are immune to
rattlesnake venom. Scientists have discovered
an enzyme in the blood of these squirrels that
stops the rattlesnake venom from working.
Squirrels who live in locations that have no
rattlesnakes do not have this immunity. It seems
that natural selection has led to certain populations of squirrels that can withstand rattlesnake
venom. Questions still exist, however, about the
squirrels’ strange behavior.
Pup Protection
Scientists tested a wide variety of squirrels
to determine their reaction to snakes. Some
squirrels lived with snakes in nature and some
lived in areas where no rattlers are found but,
all squirrels showed similar confrontational
behavior. If the snakes were found near the
squirrels’ home burrows, the taunting would
increase. The mother squirrels were even more
fierce, and watched the snakes for longer
periods of time. This behavior makes sense
because rattlesnakes are one of the primary
predators of squirrel pups. Pups do not have
the proper enzyme to resist snake venom. By
confronting a snake, the squirrel is actually
judging the threat the snake poses. The sound
of the rattle tells the squirrel how big the
snake is; bigger snakes are more dangerous
to squirrels.
What is interesting about this behavior
pattern is that all squirrels will confront a
snake, while only those who live with rattlers
in nature can resist the snake venom. This is an
example of two traits, venom resistance and
taunting behavior, changing in nature at
different rates. Perhaps the ability to resist snake
venom has been lost through evolution in
those squirrels that don’t live in snake-infested
habitats. Not enough time has passed, however,
to eliminate the confrontational behavior.
1. Why do ground squirrels confront poisonous rattlesnakes?
2. How can some squirrels survive a rattlesnake bite?
3. Explain, using natural selection, why there are two types of squirrels: those that can survive a
rattlesnake bite, and those that can’t survive a rattlesnake bite.
4. Why do squirrels that don’t live with snakes and are susceptible to snake venom still confront a
snake in a laboratory setting?
30 Traits and How They Change
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
Traits and How They Change
Traits and the Environment
A. ________________—features an organism inherits from its parents
1. Hereditary materials include genes, part of the DNA code on a _______________.
2. An organism’s genetic makeup is its __________________.
B. Environmental effects of phenotypes ______________; some influences are internal while others
are external.
1. _____________________ for environmental factors has significant effects on a population.
2. An organism’s ____________________ can change based on the environment.
3. Some fish species can change ________________ in response to the ratio of males and
females available in the population.
Section 2
Genetics
A. Genetics—science of ______________
Copyright © Glencoe/McGraw-Hill, a division of the McGraw-Hill Companies, Inc.
B. Gregor Mendel developed ____________________ of genetics by experimenting with pea plants.
1. Different forms of a gene are each called an ________________.
2. __________________ alleles show in an organism’s phenotype whenever present in its
genotype.
3. Recessive alleles show their effect in an organism’s ________________ only when two are
present in the genotype.
4. Principle of _____________________—each parent passes only one allele for a trait to its
offspring.
5. Principle of _____________________ ____________________—the alleles for one trait
do not influence the alleles for another trait.
C. Predicting genetic outcomes—Mendel used _____________________ to make predictions.
1. Reginald G. Punnett developed the ________________________ 50 years after Mendel’s
work was published.
2. When the parents’ genotypes are known, a Punnett square is used to _________________
possible offspring.
Traits and How They Change
31
Meeting Individual Needs
3. A phenotype is an organism’s visible genetic makeup and the ________________ influence
on that makeup.
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Name
Date
Class
Note-taking Worksheet (continued)
Section 3
Environmental Impact over Time
A. Over long time periods, the environment impacts a species’ ability to _________________.
1. ___________________ influences include temperature, rainfall, fire, elevation, volcanic
eruptions, periodic flooding, and pollution.
2. Availability of food, ___________________, and the number of species living in an area
affect a species’ survival.
1. ___________________________—organisms best adapted to their environment have a
higher rate of survival and reproduction than organisms less well adapted.
2. __________________—process in which DNA changes to form new alleles
3. ____________________________ involves human choice in the traits desired in offspring.
4. Adaptive ______________ occurs when one ancestral species produces several new species
over time.
5. ____________________, the end of a species, can occur for many reasons, including
destruction of an organism’s habitat and the introduction of a new species into an
environment.
Copyright © Glencoe/McGraw-Hill, a division of the McGraw-Hill Companies, Inc.
Meeting Individual Needs
B. ________________ and Wallace explained evolution—over time environmental factors can
change the genetics of a species.
32 Traits and How They Change
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Assessment
Assessment
34 Traits and How They Change
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Name
Date
Class
Traits and How They Change
Chapter
Review
Part A. Vocabulary Review
Directions: Write the correct term in the spaces beside each definition. Unscramble the boxed letters to find the
correct answer to question 10.
1. features an organism inherits from its parents
2. these alleles show their effect on the phenotype
whenever they are present in the genotype
___
___ ___ ___ ___
___ ___ ___ ___ ___ ___ ___
3. combination of actual genetic makeup
and the environmental effect on that makeup
___ ___ ___
4. an organism’s genetic makeup
___ ___ ___ ___
5. science of heredity
___ ___ ___ ___ ___
6. the demise of an entire species
___ ___ ___ ___ ___ ___ ___
7. change in DNA that forms new alleles
___ ___ ___
8. change in the genetics of a species over time
___ ___ ___ ___ ___ ___ ___
___ ___ ___ ___ ___
___ ___ ___
___ ___
___ ___
___ ___ ___ ___
___
9. organisms that are better suited to their environment survive and reproduce at a greater rate
than organisms that are not
___ ___ ___ ___ ___
___ ___ ___ ___ ___ ___ ___ ___ ___
10. production of several species from one
ancestral species is called adaptive
___ ___ ___ ___ ___ ___ ___ ___ ___
Assessment
Copyright © Glencoe/McGraw-Hill, a division of the McGraw-Hill Companies, Inc.
___
Part B. Concept Review
Directions: Fill in the Punnett square to predict the height of the offspring. Then write your prediction on the
lines provided.
1.
H
H
H
a.
b.
h
c.
d.
2.
Traits and How They Change
35
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Name
Date
Class
Chapter Review (continued)
Directions: Correctly complete each sentence by underlining the best choice in parentheses.
3. Each parent passing only one allele for a trait to its offspring is known as (segregation,
independent assortment).
4. A trait often seen in each generation is (dominant, recessive).
5. Mendel worked with (pea, bean) plants to learn about heredity.
6. Darwin’s theory proposes that changes happen from generation to generation from (adaptations,
increases) of an organism to the environment.
7. The temperature in which an organism lives is an example of a(n) (external, developmental)
environmental influence.
8. Sometimes (mutation, extinction) occurs because of the destruction of a habitat.
9. The outcome of two parents reproducing is an (offspring, allele).
Directions: Give several examples of each type of environmental effect.
10. internal
11. external
Assessment
Column I
Column II
12. Reginald C. Punnett
a. evolution by natural selection
13. Charles Darwin
b. principle of dominance
14. Gregor Mendel
c. Punnett squares
15. Alfred Russell Wallace
Directions: Answer the following questions on the lines provided.
16. What is the difference between genotype and phenotype?
17. What is Mendel’s law of independent assortment?
36 Traits and How They Change
Copyright © Glencoe/McGraw-Hill, a division of the McGraw-Hill Companies, Inc.
Directions: Match the scientist in Column I with his theory or scientific development in Column II. The items in
Column II may be used more than once.
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Transparency Activities
Transparency
Activities
Traits and How They Change
41
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Name
1
Date
Section Focus
Transparency Activity
Class
Nice Kitty
Transparency Activities
1. Describe the two environments you see pictured.
2. Why is each tiger’s coat good for its particular environment?
42 Traits and How They Change
Copyright © Glencoe/McGraw-Hill, a division of the McGraw-Hill Companies, Inc.
On a cold winter day, most people will put on a warm, heavy coat
before going outside. In a way, some animals do that, too. The large
Siberian tiger shown in the cold-weather habitat grows a thick coat
to keep warm during the winter months. The tiger’s winter coat also
is lighter in color than its summer coat. On the other hand, the tiger
in the warm-weather habitat keeps a sleek, striped coat year-round.
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Name
2
Date
Section Focus
Transparency Activity
Class
An Unpleasant Chord
1. In greenhouses, California cordgrass generally is shorter than
smooth cordgrass. Why might plant height not be a good way to
identify the species in nature?
Transparency Activities
Copyright © Glencoe/McGraw-Hill, a division of the McGraw-Hill Companies, Inc.
Waving in the marshes and mudflats along the ocean is cordgrass, a
long-leafed plant also known as marsh grass. Smooth cordgrass is an
eastern species that has invaded areas in the west where California
cordgrass grows naturally. Smooth cordgrass can form hybrids with
the native California cordgrass. Now the native species is in danger of
being overwhelmed by the invader and its hybrids.
2. California cordgrass starts flowering in July; smooth cordgrass
flowers in mid- to late August. Predict when the hybrids flower.
How might this trait be used to protect the native California cordgrass?
Traits and How They Change
43
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Name
3
Date
Section Focus
Transparency Activity
Class
The Caribbean Monk Seal
Transparency Activities
1. What could people have done to protect the Caribbean monk seal?
2. How do we know if a species no longer exists?
44 Traits and How They Change
Copyright © Glencoe/McGraw-Hill, a division of the McGraw-Hill Companies, Inc.
Over time, species can die out. Sometimes this is a natural event,
but other times it is related to what people do. In the case of the
Caribbean monk seal, frequent contact with humans and increased
hunting wiped the species out.
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Name
Date
2
Teaching Transparency
Activity
Class
Reproductive Cells/
Punnett Square
Parent Reproductive Cell
AaBbCc
ABC
ABc
AbC
Abc
Possible sex cells
aBc
abC
abc
Female (XX)
X
X
X
XX
XX
Y
XY
XY
Transparency Activities
Copyright © Glencoe/McGraw-Hill, a division of the McGraw-Hill Companies, Inc.
aBC
Male
(XY)
Traits and How They Change
45
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Name
Teaching Transparency Activity
Date
Class
(continued)
1. A parent with three different traits on three pairs of chromosomes could produce how many
genetically different sex cells?
2. What are alleles?
3. Humans have how many chromosomes?
4. In the reproductive cells, what is used to represent a dominant trait?
5. What is a Punnett square?
Transparency Activities
Copyright © Glencoe/McGraw-Hill, a division of the McGraw-Hill Companies, Inc.
6. According to the Punnett square, what percentage of offspring will be female (XX)?
46 Traits and How They Change
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Name
Date
Assessment
Transparency Activity
Class
Traits and How They
Change
Directions: Carefully review the chart and answer the following questions.
Male
r
R
RR
Rr
r
Rr
?
Female
R
1. What are the colors of the parent plants?
A The male plant is red and the female plant is white.
B The male plant is white and the female plant is red.
C Both parent plants are white.
D Both parent plants are red.
2. Which genotype will best complete this Punnett square?
F RR
G Rr
H rR
J rr
3. If the plants produce 100 offspring, approximately how many will
be white?
A 100
B 50
C 25
D0
Transparency Activities
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R–Dominant red
r–Recessive white
4. According to the information above, a white plant will be white
because _____.
F it has the genotype for white color
G it does not receive enough sunlight
H it receives too much water
J it is planted in light colored soil
Traits and How They Change
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