8th Grade Science
UNIT
Cells & Heredity
Standards Strand 4: Life Science
Concept 2: Reproduction and Heredity
PO1. Explain the purposes of cell division:
growth and repair
reproduction
PO2. Explain the basic principles of heredity using the human examples of:
eye color
widow’s peak
blood type
Topics
PO3. Distinguish between the nature of dominant and recessive traits in humans.
1. Structure of the cell
2. Meiosis & Mitosis
3. Punnett Squares
4. Dominant & recessive, co-dominance
5. Alleles/genes/chromosomes
6. Phenotype & genotype
Strand 4: Life Science
Topic: Structure of the cell
SCORE Minimum Requirement
4
In addition to score 3.0, in-depth inferences
and applications that go beyond what was
taught
3.5
In addition to score 3.0, in-depth inferences
and applications with partial success
3
TSW create an analogy for a cell.
TSW predict the repercussions of a mutation
on cell division.
TSW analyze why a single cell does not have
2 nuclei.
2.5
2
No major errors or omissions regarding 2.0
content and partial knowledge of 3.0 content
TSW explain why humans have 46
chromosomes.
TSW illustrate and label an animal cell.
TSW explain Interphase of a cell.
1.5
1
No major errors or omissions regarding 1.0
content and partial knowledge of 2.0 content
An understanding of most of the simpler
details and processes, with minimal help
when needed.
0
No information available to assess student
Sample Tasks
1. Compare the cell to a real life concept
or object and explain your analogy.
2. A cell has a mutation (problem) in its
nucleus. Predict what will happen to
the cells that it produces.
3. Jesus tells a student that a cell must
have 2 nuclei because one cell makes
2 new cells each with its own nucleus.
Determine how you would help Jesus
correct his misunderstanding.
1.
Our parents each have 46
chromosomes. Explain why we are
not born with 92 chromosomes.
2. Draw an animal cell, including and
labeling the cell membrane, nuclear
membrane, and nucleus.
3. Explain what the cell is doing during
Interphase.
1.
As an organism grows and matures
physically, what happens to its cells?
2. What is the purpose of cell division?
3. Sex cells are also known as __. How
chromosomes are in a human sex
cell?
1. As an organism grows and matures physically, what happens to its cells?
a) The individual cells grow larger.
b) The cells reproduce to make more cells.
c) The cells absorb food and water to grow larger.
d) The body parts of the organism stretch to become longer.
2. What is the purpose of cell division?
a)
b)
c)
d)
e)
f)
Growth
Repair
Reproduction
A&B
B &C
A, B, & C
3. Sex cells are also known as _________. How many chromosomes are in a human sex
cell?
a) Gametes, 46
b) Gametes, 23
c) Gabinetes, 46
d) Gabinetes, 23
4. Our parents each have 46 chromosomes. Explain why we are not born with 92
chromosomes.
5. Draw an animal cell. Make sure to include and label the cell membrane, nuclear
membrane, and nucleus.
6. Explain what the cell is doing during interphase.
7. Compare the cell to a real life concept or object and explain your analogy.
8. A cell has a mutation (problem) in its nucleus. Predict what will happen to the cells that it
produces.
9. Jesus tells a student that a cell must have 2 nuclei because one cell makes 2 new cells each
with its own nucleus. Determine how you would help Jesus correct his misunderstanding.
Strand 4: Life Science
Topic: Meiosis & Mitosis
SCORE Minimum Requirement
4
In addition to score 3.0, in-depth inferences
and applications that go beyond what was
taught
3.5
In addition to score 3.0, in-depth inferences
and applications with partial success
3
TSW analyze crossing over in meiosis.
TSW classify terms into meiosis or mitosis.
TSW find what is common between mitosis
and meiosis.
TSW compare and contrast mitosis and
meiosis.
2.5
2
No major errors or omissions regarding 2.0
content and partial knowledge of 3.0 content
TSW explain why sex cells have half the
number of chromosomes as a body cell.
TSW explain how body cells reproduce with
the full count of chromosomes.
TSW illustrate fertilization.
1.5
1
No major errors or omissions regarding 1.0
content and partial knowledge of 2.0 content
An understanding of most of the simpler
details and processes, with minimal help
when needed.
0
No information available to assess student
1. Meiosis produces…
a) Body cells
b) Sex cells
c) Hair
Sample Tasks
1. Analyze how the process of meiosis
results in offspring that are not exact
clones of one parent.
2. Classify the following words or
phrases into meiosis or mitosis: full
chromosome count, half
chromosome count, 23
chromosomes, 46 chromosomes, 4
cells produced, 2 cells produced.
3. Find what is common between
mitosis and meiosis.
4. Compare and contrast mitosis and
meiosis.
1. Explain why sex cells must have half
the chromosomes of a body cell.
2. Explain how body cells beget more
body cells with the full chromosome
count.
3. Illustrate a sperm and egg joining
together to make a zygote
(fertilization).
1. Meiosis produces…
2. Mitosis produces…
3. If a human body cell contains 46
chromosomes, how many
chromosomes does a human sex cell
contain?
d) Cancer cells
2. Mitosis produces…
a) Body cells
b) Sex cells
c) Zygotes
d) Egg cells
3. If a human body cell contains 46 chromosomes, how many chromosomes does a human sex
cell contain?
a) 46
b) 92
c) 23
d) 16
4. Explain why sex cells must have half the chromosomes of a body cell.
5. Explain how body cells produce more body cells with the full chromosome count.
6. Illustrate a sperm and egg joining together to make a zygote (fertilization).
7. Analyze how the process of meiosis results in offspring that are not exact clones of one parent.
8. Classify the following words or phrases into meiosis or mitosis: full chromosome count, half
chromosome count, 23 chromosomes, 46 chromosomes, 4 cells produced, 2 cells produced.
Mitosis
9. Find what is common between mitosis and meiosis.
10. Compare and contrast mitosis and meiosis.
Meiosis
Strand 4: Life Science
Topic: Punnett Squares
SCORE Minimum Requirement
4
In addition to score 3.0, in-depth inferences
and applications that go beyond what was
taught
3.5
In addition to score 3.0, in-depth inferences
and applications with partial success
3
TSW predict the probability of second
generation offspring.
TSW create a rule to explain a Punnett
Square.
TSW generalize why traits that are dominant
continue to show their phenotype.
2.5
2
No major errors or omissions regarding 2.0
content and partial knowledge of 3.0 content
TSW illustrate a Punnett square.
TSW determine the probability of different
offspring.
1.5
1
No major errors or omissions regarding 1.0
content and partial knowledge of 2.0 content
An understanding of most of the simpler
details and processes, with minimal help
when needed.
Sample Tasks
1. Predict the probability that the
second generation of offspring will
have dark fur (dominant) if both
parents are heterozygous for dark
fur.
2. Create a rule to explain the results of
the below Punnett Square (Image:
Punnett square for 2 homozygous
dominant parents).
3. Jakaria is convinced that she could
have a child with no widow’s peak,
even though her biological parents,
both sets of biological grandparents,
and all four sets of biological great
grandparents had widow’s peaks.
Jakaria also has a widow’s peak. Is
Jakaria right or wrong? Explain your
answer.
1. Draw a Punnett square for 2
homozygous dominant parents using
“L” to represent a widow’s peak.
2. What is the probability that
a) The offspring from the above
Punnett square are not going to
have a widow’s peak?
b) The offspring from the above
Punnett square are going to have a
widow’s peak
1. What is a Punnett square used for?
2. The 2 allele pairs on the outside
edges of the Punnett square
represent __________.
3. The 4 allele pairs inside the Punnett
square represent…
0
No information available to assess student
1. What is a Punnett square used for?
a) To predict the phenotypes of a pair of organisms’ four offspring
b) To predict the probability of genotypes of a pair of organism’s offspring
c) To predict the phenotype of an individual’s future offspring
d) To predict the probability that an individual has a mutation
2. The 2 allele pairs on the outside edges of the Punnett square represent __________.
a) Geontype of 2 offspring
b) Genotypes of 2 parents
c) Genotypes of 1 parent
d) Genotype and phenotype of 1 offspring
3. The 4 allele pairs inside the Punnett square represent…
a) 4 possible genotypes of offspring
b) 4 possible genotypes of parents
c) 4 actual genotypes of parents
d) 2 actual genotypes from a grandmother on each side of the family
4. Draw a Punnett square for 2 homozygous dominant parents using “L” to represent a
widow’s peak.
5. What is the probability that
a) The offspring from the above Punnett square are not going to have a widow’s peak?
b)The offspring from the above Punnett square are going to have a widow’s peak?
6. Predict the probability that the second generation of offspring will have dark fur
(dominant) if both parents are heterozygous for dark fur.
7. Create a rule to explain the results of the below Punnett Square.
8. Jakaria is convinced that she could have a child with no widow’s peak, even though her
biological parents, both sets of biological grandparents, and all four sets of biological great
grandparents had widow’s peaks. Jakaria also has a widow’s peak. Is Jakaria right or
wrong? Explain your answer.
Strand 4: Life Science
Topic: Phenotype & genotype
SCORE Minimum Requirement
4
In addition to score 3.0, in-depth inferences
and applications that go beyond what was
taught
3.5
In addition to score 3.0, in-depth inferences
and applications with partial success
3
TSW create general statements based on
knowledge as to why genotype cannot solely
be determined by phenotype.
TSW compare and contrast genotype and
phenotype.
TSW predict the presence of dominant and
recessive traits in a given population.
2.5
2
No major errors or omissions regarding 2.0
content and partial knowledge of 3.0 content
TSW explain how to determine an
individual’s phenotype based on genotype.
TSW explain possible genotypes for a
widow’s peak phenotype.
TSW describe how the genotype of recessive
traits can more easily be determined from
phenotype than of dominant traits.
Sample Tasks
1. Create generalizing statements to
explain why it’s not as easy to figure
out an individual’s genotype based on
his/her phenotype (versus phenotype
based on genotype).
2. Compare and contrast genotype and
phenotype.
3. Before white bunnies settled into the
Glendale region, there used to only
be brown bunnies. This means that
the brown bunnies had brown fur,
brown eyes, etc. Eventually, some
white bunnies settled into the same
area as the brown bunnies. These
white bunnies began to mate with the
brown bunnies. Predict what
happened to the brown bunnies’
physical traits after they mated with
the white bunnies.
1. Explain how to figure out an
individual’s phenotype based on
his/her genotype.
2. What is/are the possible genotype(s)
for an individual with a widow’s
peak? Explain how you got that
answer.
3. Juan looked at a picture of Marissa
and her family and noticed that they
all had blond hair and blue eyes. He
said, “I bet I can tell you the genotype
for your eye color and hair color.”
Marissa was doubtful. Why was Juan
so sure that he could figure out
Marissa’s eye color and hair color
genotypes, without doing genetic
testing?
1.5
1
No major errors or omissions regarding 1.0
content and partial knowledge of 2.0 content
An understanding of most of the simpler
details and processes, with minimal help
when needed.
0
No information available to assess student
1.
2.
3.
4.
Define phenotype.
Define genotype.
Provide 3 examples of phenotype.
Provide 3 examples of genotype.
1. Define phenotype.
a) The observable characteristics of an individual
b) The genetic chracterisitics of an individual
c) The environmental impact on an individual’s traits
d) The entire list of an individual’s genetic material
2. Define genotype.
a) The observable characteristics of an individual
b) The genetic chracterisitics of an individual
c) The environmental impact on an individual’s traits
d) The entire list of an individual’s genetic material
3. Provide 3 examples of phenotypes.
a)
b)
c)
4. Provide 3 examples of genotypes.
a)
b)
c)
5. Explain how to figure out an individual’s phenotype based on his/her genotype.
6. What is/are the possible genotype(s) for an individual with a widow’s peak? Use “B.”
Explain how you got that answer.
7. Juan looked at a picture of Marissa, her parents, both sets of grandparents, and all four
great grandparents and noticed that they all had blonde hair and blue eyes. He said, “I bet I
can tell you the genotype for your eye color and hair color.” Marissa was doubtful. Why is
Juan so sure that he could figure out Marissa’s eye color and hair color genotypes, without
doing genetic testing?
8. Create generalizing statements to explain why it’s not as easy to figure out an individual’s
genotype based on his/her phenotype (versus phenotype based on genotype).
9. Compare and contrast genotype and phenotype.
10. Before white bunnies settled into the Glendale region, there used to only be brown bunnies.
This means that the brown bunnies had brown fur, brown eyes, etc. Eventually, some white
bunnies settled into the same area as the brown bunnies. These white bunnies began to
mate with the brown bunnies. Predict what happened to the brown bunnies’ physical traits
after they mated with the white bunnies.
Strand 4: Life Science
Topic: Dominant & recessive, co-dominance
SCORE Minimum Requirement
4
In addition to score 3.0, in-depth inferences
and applications that go beyond what was
taught
3.5
In addition to score 3.0, in-depth inferences
and applications with partial success
3
TSW compare and contrast dominant and
co-dominant traits.
TSW categorize different dominant and
recessive traits.
TSW predict a second generation’s
offspring’s blood type.
2.5
2
No major errors or omissions regarding 2.0
content and partial knowledge of 3.0 content
TSW illustrate a Punnett square.
TSW determine the probability of different
offspring.
TSW explain the concept of co-dominance.
1.5
1
No major errors or omissions regarding 1.0
content and partial knowledge of 2.0 content
An understanding of most of the simpler
details and processes, with minimal help
when needed.
0
No information available to assess student
Sample Tasks
1. Compare and contrast a dominant
trait with a co-dominant trait.
2. Categorize the following as dominant
or recessive: blue eyes, brown eyes,
widow’s peak, no widow’s peak, etc.
3. Predict what the second generation’s
blood types may be if the parent
generation had 2 individuals that
both had OO blood type.
1. Draw a Punnett square to show the
possible combinations for the
offspring of a heterozygous partner
and a homozygous recessive partner.
2. What is the probability that a
homozygous dominant individual
and a homozygous recessive
individual would have homozygous
recessive offspring?
3. Explain how co-dominance works.
1. Define recessive trait.
2. List the possible gene combinations
for a person with a widow’s peak,
using “B” to symbolize the dominant
trait.
3. _________ is an example of codominance.
1. Define recessive trait.
a) An interherited trait that is only seen when 2 copies of the allele are present
b) An inherited trait that is only seen when 2 different alleles are present
c) A set of alleles where neither is dominant over the other
d) A set of alleles that blend together
2. List the possible gene combinations for a person with a widow’s peak, using “B” to symbolize
the dominant trait.
3. _________ is an example of co-dominance.
a) Eye color
b) Skin color
c) Blood type
d) Gender
4. Draw a Punnett square to show the possible combinations for the offspring of a heterozygous
partner and a homozygous recessive partner. Use “G.”
5. What is the probability that a homozygous dominant individual and a homozygous recessive
individual would have homozygous recessive offspring? Use “A.”
Answer: __________
6. Explain how co-dominance works.
7. Compare and contrast a dominant trait with a co-dominant trait.
8. Categorize the following as dominant or recessive: blue eyes, brown eyes, widow’s peak, and no
widow’s peak.
Dominant
Recessive
9. Predict what the second generation’s blood types may be if the parent generation had 2
individuals that both had OO blood type.
Strand 4: Life Science
Topic: Alleles/genes/chromosomes
SCORE Minimum Requirement
4
In addition to score 3.0, in-depth inferences
and applications that go beyond what was
taught
3.5
In addition to score 3.0, in-depth inferences
and applications with partial success
3
TSW compare and contrast genes and
alleles.
TSW predict logical consequences of a
recessive trait as it is crossed with dominant
traits.
TSW create rules to explain why recessive
alleles have not died out.
2.5
2
No major errors or omissions regarding 2.0
content and partial knowledge of 3.0 content
TSW explain how recessive traits do not
always show in the phenotype of an
individual.
TSW describe how genes and chromosomes
share in commonalities.
1.5
1
0
TSW draw a diagram of alleles attached to a
chromosome.
No major errors or omissions regarding 1.0
content and partial knowledge of 2.0 content
An understanding of most of the simpler
details and processes, with minimal help
when needed.
Sample Tasks
1. Compare and contrast genes and
alleles.
2. Predict what will happen to a
parent’s blue eye allele that it passed
down to the first generation if the
later (second, third, and onward)
generations partner with brown-eyed
individuals.
3. Write out some generalizing
statements to explain why the alleles
for blue eyes or no widow’s peak
haven’t “died out.”
1. Explain how a person can have an
allele for blue eyes yet have brown
eyes.
2. Describe how a gene and
chromosome are interrelated.
3. Draw a diagram to show how alleles
are attached to a chromosome.
1. Define gene.
2. Give an example of an allele.
3. A human has 46 ______ but up to
120,000 _____ that code for our
many traits.
No information available to assess student
1. Define gene.
a) A unit of heredity transferred from parent to offspring
b) One form of a gene
c) The entire list of genetic material for an individual
d) A threadlike structure of DNA materialfound in the nucleus
2. Which is an example of an alelle?
a) Skin color
b) Female gender
c) Blue eyes
d) Eye color
3. A human has 46 ______ but up to 120,000 _____ that code for our many traits.
a) Alleles; genes
b) Genes; chromosomes
c) Genes; alleles
d) Chromosomes; genes
4. Explain how a person can have an allele for blue eyes yet have brown eyes.
5. Describe how a gene and chromosome are interrelated.
4. Draw a diagram to show how alleles are attached to a chromosome.
5. Compare and contrast genes and alleles.
6. Predict what will happen to a parent’s blue eye allele that it passed down to the first generation
if the later (second, third, and onward) generations partner with brown-eyed individuals.
4. Write out some generalizing statements to explain why the alleles for blue eyes or no widow’s
peak haven’t “died out.”