Enrichment/Instructional Packet - SCIENCE, GRADE 7 - SCIENCE - Enrichment/Instructional ...
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SCIENCE, GRADE 7
Enrichment/Instructional Packet
April 20, 2020- May 1, 2020
SCIENCE
Prince George’s County Public Schools
Division of Academics
Department of Curriculum and Instruction
The teacher will not grade this packet.
April 20th – April 24th
Topic 1: Genetic Variation-
Think about this question as you work through the activities.
Essential Question: How do organisms differ in sexual reproduction and asexual reproduction?
Text 1
Read the passage titled “How Is Asexual Reproduction Different from Sexual Reproduction?
Part 1”. You will read about asexual and sexual reproduction in order to complete the task below.
Please be sure to annotate the text. You will be able to use evidence from this text in your
constructed response.
How Is Asexual Reproduction Different from Sexual Reproduction? Part 1
In sexual reproduction, plants and animals create offspring by combining their genetic material. Two parent
organisms produce gametes that come together through fertilization. Asexual reproduction involves only one
parent that replicates its genetic material and produces offspring. Unlike sexual reproduction, asexual
reproduction does not require mating.
Green plants use both sexual and asexual reproduction throughout their life cycles. Each generation alternates
between the two mechanisms. Plants will produce spores asexually that give rise to offspring. Those offspring
then produce gametes that fuse in sexual reproduction to create genetic diversity. Some flowering plants, such
as orchids, release pollen that is transported to other orchids by bees and butterflies. The transported pollen
enters the flower and fertilizes the egg to form a new seed. The seed is released from the orchid and grows
into a new flower that is a genetic cross of the two parent orchids. You have probably eaten rice, wheat, and
corn. These crops are other examples of plants that reproduce sexually. They differ from orchids and other
flowering plants in that the pollen is transported by wind. By reproducing sexually, these crops can evolve to
succeed in different environments.
Organisms that reproduce asexually typically produce many offspring in a relatively short amount of time. In
contrast, most mammals that reproduce sexually have a long gestation period and only produce one or a few
offspring. A single elephant calf develops over 21 months in the mother’s womb! Organisms such
as bacteria that reproduce asexually may produce one offspring every few minutes. Fungi produce thousands
of spores and release them into the environment. They will grow into new individuals under the right
environmental conditions.
Task: On your own paper, create a table and place each of the phrases under the correct organism. Some
phrases may be used more than once.
• Many offspring
• 1-2 offspring
• Long gestational period
• Short life cycles
• Produces spores
• Produces gametes
• One parent
• Two parents
2
Text 2
Read the passage titled “How Is Asexual Reproduction Different from Sexual Reproduction?
Part 2”. You will read about asexual and sexual reproduction in order to complete the task below.
Please be sure to annotate the text. You will be able to use evidence from this text in your
constructed response.
How Is Asexual Reproduction Different from Sexual Reproduction? Part 2
Offspring of asexual reproduction receive a complete copy of the single parent’s chromosomes. Therefore,
offspring of asexual reproduction are genetically identical to each other and to the parent. This is why the
offspring look like the parent and each other. In some cases, organisms that reproduce asexually have half the
genetic material of the parent. Honeybees are an example of organisms that sometimes use parthenogenesis.
Bees that develop from an unfertilized egg become drones while fertilized eggs develop into worker bees. The
drone honeybee has only one copy of each chromosome from the parent.
There are advantages to both sexual and asexual reproduction. Organisms that have a genetic abnormality
and produce asexually will pass that abnormality on to all of their offspring. In contrast, in sexual reproduction,
the formation of gametes may eliminate the genetic abnormality from the offspring’s genetic material. This is
because each parent passes on only one of its two alleles for a particular gene. If the normal allele is passed
on, the abnormality is eliminated from the offspring’s genetic material.
Mutations in genetic material can cause abnormalities or even death in offspring. In asexual reproduction, only
one set of genetic material is being processed and replicated, resulting in fewer opportunities for errors to be
introduced. Mutations can also be beneficial to offspring. For example, a mutation in a bacterium’s genetic
material may result in resistance to an antibiotic. Once that mutation is introduced, it will be passed on to all the
bacterium’s offspring rather quickly by asexual reproduction.
Task: On your own paper, create a table like the one below and place each of the phrases under the
advantage/disadvantage.
• Does not require mating
• Provides less chances for harmful mutations to be passed on
• Increases genetic variation
• Provides a greater chance for harmful mutations to be passed on
• Requires mating
• Produces fewer offspring over a long time period
• Produces little or no genetic variation in offspring
• Produces many offspring quickly
Asexual Reproduction Sexual Reproduction
Advantage Disadvantage Advantage Disadvantage
3Constructed Response
Guiding Question: During asexual reproduction, organisms reproduce using only mitosis. Describe
some genetic implications (positive and negative) that these organisms will face due to this.
Use your own paper to record your thoughts in a graphic organizer similar to the one below. Make
sure that you leave enough space to record information in all sections of the organizer. Consider
using at least two positive and two negative implications in your response. Then, write your
constructed response in paragraph form on your own paper. Be sure to review the rubric to make
sure that your explanation contains all of the appropriate pieces. An image comparing mitosis and
meiosis has been included to assist you. You may use your textbook if you need more information.
Image of mitosis and meiosis
Sample Graphic Organizer
Genetic Implications Faced by Organisms Undergoing Asexual Reproduction
Positive implication 1
Positive implication 2
Negative implication 2
Negative implication 2
4Rubric for Writing
3 2 1 0
There is evidence in There is evidence in There is evidence in There is evidence that
this response that this response that the this response that the the student has no
the student has a full student has a general student has a minimal understanding of the
and complete understanding of the understanding of the solution to a problem or
understanding of the solution to a problem solution to a problem the question.
solution to a problem or constructs a or constructs a
• The response is
or constructs a general explanation of minimal explanation of
completely incorrect, too
complete explanation the question. the question.
vague, or irrelevant to the
of the question.
• Provides a solution or • Provides a solution or solution or question
• Provides a solution or explanation that is explanation that is
explanation that is mostly coherent and minimally based on
coherent and based on based on disciplinary disciplinary core ideas
disciplinary core ideas core ideas
• Reflects little or no
• Reflects a complete • Reflects some synthesis of
synthesis of synthesis of understanding of
understanding of understanding of complex ideas and
complex ideas and complex ideas and crosscutting concepts
crosscutting concepts crosscutting concepts
April 27th – May 1st
Topic 2: Survival-
Think about this question as you work through the activities.
Essential Question: How does genetic variation in a population increase some individual’s probability
of surviving and reproducing?
Text
Read the passage titled “How Does Genetic Variation Lead to Natural Selection and
Adaptation?” Be sure to annotate the text. You will be able to use this information to complete the
scientific explanation.
How Does Genetic Variation Lead to Natural Selection and Adaptation?
All organisms are constantly working to survive. For example, in a population of mice, each mouse is involved
in searching for food, avoiding predators, finding a mate, caring for young, and much more. Any gene that
provides it with a characteristic that helps with one or more of these jobs will aid the mouse’s survival. For
example, a mouse with a brown coat is far more likely to survive on the forest floor than one with a trait for a
white coat. The process whereby better adapted organisms, like the brown mouse, are likely to survive and
reproduce is called natural selection.
Because natural selection works on all the organisms in a population, it can alter how common a gene is in that
population. If natural selection removes white mice from our forest population, the gene for white coat will
become less frequent. It may even eventually disappear. The change in gene frequency within a population is
called evolution.
Evolution has been observed many times. Some of the best-known studies have been done on finches in the
Galapagos Islands. These finches, first made famous by Charles Darwin, have been studied for many years.
5They have been seen to adapt to changes in the environment. For example, the beak size in one species of
small ground finch has been shown to be an adaptation that determines the size of seeds a bird can eat. The
ground finch population showed a variation in beak size. During a drought, individual birds with deep strong
beaks could crack open big seeds. Those with smaller beaks could only feed on small seeds. They had less
food, and fewer survived the drought. As a result of the drought, genes for big beaks increased in frequency in
the population as more big-beaked birds survived. A bigger proportion of the population was adapted to crack
open big seeds.
Natural selection can account for all the strange and complex adaptations we can observe in living organisms.
As a result, organisms have been able to adapt to some of the harshest environments on Earth.
Task: Finch Adaptations
Look at these data. Beak depth, the distance from the top to the bottom of the beak, is controlled by the bird's
genes. The bar chart shows the variation in beak size before a drought. The survival of birds after the drought
with a particular bill depth is shown by the yellow line.
Scientific Explanation
Guiding Question: Explain how the graph supports the idea of natural selection among the finches.
Use your own paper to record your claim, evidence, and reasoning thoughts in a graphic organizer similar to
the one below. Make sure that you leave enough space to record information in all three sections of the
CER. Then, write your scientific explanation in paragraph form on your own paper. Be sure to review the
CER rubric to make sure that your explanation (essay) contains all of the appropriate pieces.
6Claim, Evidence, and Reasoning (CER) Student Graphic Organizer
C
(Claim)
A statement that answers the guiding question.
E
(Evidence)
Provide scientific data to support your claim. The evidence should be
relevant and sufficient. The analysis of the data should include a
trend, difference, or relationship. The interpretation explains what the
analysis means. This can be listed here in bullet points. Include at
least 3 pieces of evidence.
R
(Reasoning)
Use scientific principles and knowledge that you have about the topic
to explain why your evidence supports the claim.
Claim, Evidence, and Reasoning Rubric for Writing
Scale
Criteria 3 2 1 0
Claim The claim includes a testable The claim includes a testable The claim includes a statement No response,
statement or conclusion that statement or conclusion that that answers some components or response
fully answers all components of answers most components of of the question. not
the question. the question. appropriate.
Evidence Data included in the Data included in the explanation Data included in the explanation No response,
explanation helps answer the helps answer the question or helps answer the question or or response
question. Data comes from a problem, OR data comes from a problem, OR data comes from a not
variety of resources. Evidence variety of resources, AND variety of resources, OR appropriate.
is both appropriate and evidence is both appropriate evidence is both appropriate
sufficient. and sufficient. and sufficient.
Reasoning The reasoning describes why The reasoning describes why The reasoning describes why No response,
the evidence is relevant and the evidence is relevant and the evidence is relevant and or response
should be used to support the should be used to support the should be used to support the not
claim. The explanation includes claim, OR the explanation claim, OR the explanation appropriate.
reasoning for how the evidence includes reasoning for how the includes reasoning for how the
supports the claim. Scientific evidence supports the claim. evidence supports the claim.
principles and scientific Scientific principles and Scientific principles OR
language link the evidence to scientific language link the scientific language link the
the claim. evidence to the claim. evidence to the claim.
7Science 7 Enrichment Packet ANSWER KEY: April 20, 2020- May 1, 2020
Topic 1: Genetic Variation-
Task: Responses
Bacteria Mammal Plant
Many offspring 1-2 offspring Many offspring
Short life cycles Long gestational period Produces spores
One parent Two parents One parent
Produces gametes
Task: Responses
Asexual Reproduction Sexual Reproduction
Advantage Disadvantage Advantage Disadvantage
• Does not require • Provides a • Provides less • Requires mating
mating greater chance chance for • Produces fewer
• Produces many for harmful harmful mutations offspring over a
offspring quickly mutations to be to be passed on long time period
passed • Increases genetic
• Produces little or variation
no genetic
variation in
offspring
Scientific Explanation:
Sample responses might include: Organisms that reproduce through asexual reproduction are able to
reproduce with only one parent since the joining of gametes is not needed for reproduction to occur. Due to
this, organisms will be less diverse than those who can sexually reproduce and use meiosis. Responses
should include at least two positive and two negative implications.
Topic 2: Survival-
Task: Finch Adaptations
Sample response: The data in this chart show a connection between beak depth and survival in finches. The
data supports the idea that natural selection is occurring among the finches. Finches born with deep beaks
have a higher rate of survival in this study than finches with beaks with smaller depth. This suggests that
finches with deep beaks are better adapted to live in their environment.
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