Endocrine and Reproductive Systems
Title: Human Development
Grade Level: 9–12
Subject/Content: Science/Biology
Summary of Lesson: Students will be introduced to the process of sex cell formation, the
uniting of these cells and the process of human development that follows.
Focus Question: How do two microscopic cells unite and then create an infant, with
trillions of cells, within nine months?
Resource: Science in Context
Procedures:
Steps/Activites by Teacher:
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Ask students to discuss how a single unfertilized egg becomes an infant, with trillions
of cells, within nine months.
Draw a large circle to represent the outline of a cell during meiosis I. Next, draw two
circles side-by-side to represent the outline of two cells simultaneously undergoing
meiosis II.
Use twelve pipe cleaners of at least six different colors to demonstrate and explain a
DNA strand.
Represent and explain a super coiled condensed sister chromatid by coiling a pipe
cleaner around a pencil. Lay them across each other to create six whole
chromosomes.
Next, have students draw a diagram showing the stages of meiosis I.
Direct students to Science in Context. Instruct them to search for meiosis to find the
article "Meiosis." Biology. Ed. Richard Robinson. New York: Macmillan Reference
USA, 2009., and images of meiosis.
Instruct students to read the first three sections of the article and examine the
images they have found. Once students have finished, introduce the stages of
meiosis II by drawing them on the board.
Instruct students to read the section of the article titled "Meiosis II and Cytokinesis."
Break students into small groups and have the groups discuss the connections
between the stages of meiosis I and II and the original question, "How do two
microscopic cells unite and then create an infant, with trillions of cells, within nine
months?"
Have groups of students share their ideas with the class.
Show a video such as The Miracle of Life as a visual demonstration of the uniting of
sex cells. Students can also further search Science in Context for additional
information on meiosis, including reference articles, images, and journal articles.
Next, have students discuss the connections between what they viewed in the video,
the stages of meiosis I and II, and the question, "How do two microscopic cells unite
and then create an infant, with trillions of cells, within nine months?"
Steps/Activities by Student(s):
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Draw a diagram illustrating the stages of meiosis I.
Using Science in Context, locate the article "Meiosis." Biology. Ed. Richard Robinson.
New York: Macmillan Reference USA, 2009., and images of meiosis.
Read assigned sections of the article and examine the images you have found.
Discuss the connection between the stages of meiosis I and II with the question,
"How do two microscopic cells unite and then create an infant, with trillions of cells,
within nine months?"
Share your ideas with the class.
Watch a video such as The Miracle of Life and discuss the connection between it, the
stages of meiosis I and II, and the question, "How do two microscopic cells unite and
then create an infant, with trillions of cells, within nine months?"
Outcome: Students will be able to explain how human sex cells form, unite, and develop
into a trillion cell organism in nine months.
Related Activities:
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Math/Science
Discuss the probability of two cells uniting to create an infant.
Standards Alignment
Next Generation Science Standards
LS1.DCI.A:1. Systems of specialized cells within organisms help them perform the essential
functions of life. (HS-LS1-1)
LS1.DCI.A:3. Multicellular organisms have a hierarchical structural organization, in which
any one system is made up of numerous parts and is itself a component of the next level.
(HS-LS1-2)
LS1.DCI.B:1. In multicellular organisms individual cells grow and then divide via a process
called mitosis, thereby allowing the organism to grow. The organism begins as a single cell
(fertilized egg) that divides successively to produce many cells, with each parent cell
passing identical genetic material (two variants of each chromosome pair) to both daughter
cells. Cellular division and differentiation produce and maintain a complex organism,
composed of systems of tissues and organs that work together to meet the needs of the
whole organism. (HS-LS1-4)
HS-LS3-1. Ask questions to clarify relationships about the role of DNA and chromosomes in
coding the instructions for characteristic traits passed from parents to offspring.
Standard Source: Next Generation Science Standards (2013)
Common Core State Standards
Grades 9-10
CCSS.ELA-Literacy.RST.9-10.2
Determine the central ideas or conclusions of a text;
trace the text's explanation or depiction of a complex process, phenomenon, or concept;
provide an accurate summary of the text.
CCSS.ELA-Literacy.RST.9-10.3
Follow precisely a complex multistep procedure when
carrying out experiments, taking measurements, or performing technical tasks attending to
special cases or exceptions defined in the text.
CCSS.ELA-Literacy.RST.9-10.4
Determine the meaning of symbols, key terms, and
other domain-specific words and phrases as they are used in a specific scientific or technical
context relevant to grades 9-10 texts and topics.
CCSS.ELA-Literacy.RST.9-10.5
Analyze the structure of the relationships among
concepts in a text, including relationships among key terms (e.g., force, friction, reaction
force, energy).
CCSS.ELA-Literacy.RST.9-10.7
Translate quantitative or technical information expressed
in words in a text into visual form (e.g., a table or chart) and translate information
expressed visually or mathematically (e.g., in an equation) into words.
CCSS.ELA-Literacy.RST.9-10.9
Compare and contrast findings presented in a text to
those from other sources (including their own experiments), noting when the findings
support or contradict previous explanations or accounts.
CCSS.ELA-Literacy.RST.9-10.10
By the end of grade 10, read and comprehend
science/technical texts in the grades 9-10 text complexity band independently and
proficiently.
CCSS.ELA-Literacy.WHST.9-10.4 Produce clear and coherent writing in which the
development, organization, and style are appropriate to task, purpose, and audience.
CCSS.ELA-Literacy.WHST.9-10.6 Use technology, including the Internet, to produce,
publish, and update individual or shared writing products, taking advantage of technology's
capacity to link to other information and to display information flexibly and dynamically.
CCSS.ELA-Literacy.WHST.9-10.7 Conduct short, as well as more sustained research
projects, to answer a question (including a self-generated question) or solve a problem;
narrow or broaden the inquiry when appropriate; synthesize multiple sources on the
subject, demonstrating understanding of the subject under investigation.
CCSS.ELA-Literacy.WHST.9-10.8 Gather relevant information from multiple authoritative
print and digital sources, using advanced searches effectively; assess the usefulness of each
source in answering the research question; integrate information into the text selectively to
maintain the flow of ideas, avoiding plagiarism and following a standard format for citation.
CCSS.ELA-Literacy.WHST.9-10.9
analysis, reflection, and research.
Draw evidence from informational texts to support
CCSS.ELA-Literacy.WHST.9-10.10 Write routinely over extended time frames (time for
reflection and revision) and shorter time frames (a single sitting or a day or two) for a range
of discipline-specific tasks, purposes, and audiences.
Grades 11-12
CCSS.ELA-Literacy.RST.11-12.2
Determine the central ideas or conclusions of a text;
summarize complex concepts, processes, or information presented in a text by paraphrasing
them in simpler but still accurate terms.
CCSS.ELA-Literacy.RST.11-12.3
Follow precisely a complex multistep procedure when
carrying out experiments, taking measurements, or performing technical tasks; analyze the
specific results based on explanations in the text.
CCSS.ELA-Literacy.RST.11-12.4
Determine the meaning of symbols, key terms, and
other domain-specific words and phrases as they are used in a specific scientific or technical
context relevant to grades 11-12 texts and topics.
CCSS.ELA-Literacy.RST.11-12.5
Analyze how the text structures information or ideas into
categories or hierarchies, demonstrating understanding of the information or ideas.
CCSS.ELA-Literacy.RST.11-12.7
Integrate and evaluate multiple sources of information
presented in diverse formats and media (e.g., quantitative data, video, multimedia) in order
to address a question or solve a problem.
CCSS.ELA-Literacy.RST.11-12.8
Evaluate the hypotheses, data, analysis, and conclusions
in a science or technical text, verifying the data when possible and corroborating or
challenging conclusions with other sources of information.
CCSS.ELA-Literacy.RST.11-12.9
Synthesize information from a range of sources (e.g.,
texts, experiments, simulations) into a coherent understanding of a process, phenomenon,
or concept, resolving conflicting information when possible.
CCSS.ELA-Literacy.RST.11-12.10 By the end of grade 12, read and comprehend
science/technical texts in the grades 11-12 text complexity band independently and
proficiently.
CCSS.ELA-Literacy.WHST.11-12.2a Introduce a topic and organize complex ideas, concepts,
and information so that each new element builds on that which precedes it to create a
unified whole; include formatting (e.g., headings), graphics (e.g., figures, tables), and
multimedia when useful to aiding comprehension.
CCSS.ELA-Literacy.WHST.11-12.2b Develop the topic thoroughly by selecting the most
significant and relevant facts, extended definitions, concrete details, quotations, or other
information and examples appropriate to the audience's knowledge of the topic.
CCSS.ELA-Literacy.WHST.11-12.4 Produce clear and coherent writing in which the
development, organization, and style are appropriate to task, purpose, and audience.
CCSS.ELA-Literacy.WHST.11-12.6 Use technology, including the Internet, to produce,
publish, and update individual or shared writing products in response to ongoing feedback,
including new arguments or information.
CCSS.ELA-Literacy.WHST.11-12.7 Conduct short, as well as more sustained research
projects, to answer a question (including a self-generated question) or solve a problem;
narrow or broaden the inquiry when appropriate; synthesize multiple sources on the
subject, demonstrating understanding of the subject under investigation.
CCSS.ELA-Literacy.WHST.11-12.8 Gather relevant information from multiple authoritative
print and digital sources, using advanced searches effectively; assess the strengths and
limitations of each source in terms of the specific task, purpose, and audience; integrate
information into the text selectively to maintain the flow of ideas, avoiding plagiarism and
overreliance on any one source and following a standard format for citation.
CCSS.ELA-Literacy.WHST.11-12.9 Draw evidence from informational texts to support
analysis, reflection, and research.
CCSS.ELA-Literacy.WHST.11-12.10 Write routinely over extended time frames (time for
reflection and revision) and shorter time frames (a single sitting or a day or two) for a range
of discipline-specific tasks, purposes, and audiences.
Standard Source: Common Core State Standards Initiative (2010)