Week 5: Week 5 Content
Grade 7 Science | Rosche | Kairos Academies
**Scientists Like Us:** In this lesson, you'll work as a team of scientists investigating [topic-specific content]. Every scientist brings unique perspectivesβyour ideas matter!
**Community Connection:** This phenomenon affects our community in [topic-specific content]. You'll investigate how scientists use evidence to understand [topic-specific content] in places like ours.
**Progress Checkpoint:** You've completed [topic-specific content]. Next up: [topic-specific content].
**Pair-Share:** First, think about [topic-specific content] on your own (1 min). Then share with your partner (2 min). Finally, we'll discuss as a class.
Accessibility & Learning Support
- Need text read aloud? Chrome: Right-click then "Read aloud" | Edge: Click speaker icon in address bar
- Working from home? Look for the HOME ALTERNATIVE boxes at each station
- Need extra support? Click the green "Need help?" buttons for hints and sentence starters
- Stuck? Look for the red "Stuck?" boxes with step-by-step help
NGSS Standards Covered This Week
MS-LS3-2 (Primary)
What it means: Develop and use a model to describe why asexual reproduction results in offspring with identical genetic information and sexual reproduction results in offspring with genetic variation.
In student language: I can model how different types of reproduction affect genetic diversity in offspring.
MS-LS1-5 (Secondary)
What it means: Construct a scientific explanation based on evidence for how environmental and genetic factors influence the growth of organisms.
In student language: I can explain how both genes and environment affect how organisms grow and develop.
3-Dimensional Learning
| Dimension | What You'll Practice |
|---|---|
| SEP-2 Developing & Using Models | Use Punnett squares to predict inheritance |
| DCI LS3.A Inheritance of Traits | Learn how traits pass from parents to offspring |
| DCI LS3.B Variation of Traits | Understand why siblings look different |
| CCC-2 Cause and Effect | Connect genes to observable traits |
Success Criteria - How You'll Know You've Got It
Target 1: Explain how chromosomes carry genetic information
Self-check: Can I explain why we have chromosome pairs?
Target 2: Use Punnett squares to predict trait inheritance
Self-check: Can I predict offspring ratios for a simple trait?
Target 3: Distinguish between genotype and phenotype
Self-check: Can I explain the difference between what genes you have and what you look like?
Why This Matters to YOU:
You inherited half your DNA from each parent, creating a unique combination that's 100% you. Understanding heredity explains family resemblances, genetic conditions, and how farmers breed better crops.
Meet a Geneticist: Dr. Mary-Claire King
Who: Dr. King is a groundbreaking geneticist who discovered the BRCA1 gene - the first gene proven to increase risk of breast and ovarian cancer when mutated. Her work transformed how families understand inherited health risks.
Research Connection to This Week: Dr. King's discovery proved that cancer susceptibility can be inherited just like eye color or height! Using the same Punnett square logic you're learning, genetic counselors help families predict the probability that children will inherit BRCA1 mutations. If a parent has one mutated copy (Bb) and one normal copy (BB), each child has a 50% chance of inheriting the mutation - exactly like the trait crosses you'll practice in Station 2. This real-world application has saved thousands of lives through early screening and prevention.
Career Pathway: Dr. King earned her PhD in genetics from UC Berkeley and spent 17 years proving BRCA1's connection to cancer - many scientists told her it was impossible! She also helped identify victims of human rights violations in Argentina by matching DNA from grandmothers to grandchildren, showing how heredity patterns can reunite families separated by tragedy.
Why It Matters: Because of Dr. King's work, families can now make informed health decisions. In St. Louis's diverse communities, genetic testing helps people from all backgrounds - African American, Latina, Asian, and White families - understand their unique cancer risks. However, genetic counseling and testing are often more accessible to wealthy families, creating health equity concerns. Understanding heredity empowers YOU to advocate for equal access to genetic healthcare in your community.
St. Louis's Genetic Diversity: A Living Laboratory
St. Louis is a richly diverse city - home to immigrant communities from across the globe and people from every continent. Missouri's population reflects significant genetic diversity: communities of African American, Hispanic/Latino, Asian American, Bosnian, and other backgrounds. This diversity isn't just cultural - it represents millions of years of human evolution and adaptation to different climates, diets, and environments around the globe.
Why This Matters for Heredity: When you use Punnett squares this week, you're predicting traits in the same diverse populations that make St. Louis special. Genetic variation - the differences in alleles between people - provides evolutionary advantages. For example, the sickle cell allele (which causes disease when inherited from both parents) actually protects against malaria when inherited from just one parent. This allele is more common in West African, Mediterranean, and South Asian populations where malaria was historically prevalent. St. Louis's genetic diversity means disease resistance, unique adaptations, and combinations of traits that help our community thrive.
Your Family's Story: Every St. Louis student carries a unique genetic heritage. Maybe you inherited your grandmother's dark eyes, your father's height, or your mother's curly hair. These traits traveled through generations using the same chromosome pairing and inheritance patterns you'll model in Punnett squares today. Ask your family: What traits "run in the family"? Which traits skipped a generation? You're carrying genetic information that tells the story of human migration, survival, and adaptation across thousands of years - and St. Louis is where all those stories come together.
Heredity & Health Equity in St. Louis Communities
Why is sickle cell trait more common in African American populations? The answer connects heredity to environmental adaptation. The sickle cell allele provides protection against malaria in regions where malaria is endemicβWest Africa, where many Black Americans' ancestors lived. In St. Louis, Washington University Medical Center and Siteman Cancer Center offer genetic counseling to help families understand hereditary conditions. Dr. Jennifer Doudna, Nobel Prize winner and CRISPR pioneer, studies how we might edit genes to treat hereditary diseases like sickle cell anemia. Understanding alleles isn't just about inheriting eye colorβit's about health equity, ancestry, and ensuring all St. Louis communities have access to genetic screening and treatment. Genetic counselors ($65k-$95k), medical geneticists ($180k-$280k), and researchers work to make treatments accessible.
The Phenomenon: The Sibling Similarity Mystery
Consider this puzzling observation:
- Identical twins look exactly alike - same eye color, hair color, height
- Some siblings share many traits (both have brown eyes, curly hair)
- Other siblings look very different from each other
- All siblings have the same two parents
If children get their genes from the same parents, why don't all siblings look identical? How does nature create so much variety?
Focus Question: Why do some siblings look alike while others look completely different?
Learning Targets
By the end of this week, you will be able to:
Vocabulary
Cognate Strategy: Many science words look similar in English and Spanish β use your Spanish to learn science!
| Term | Spanish | Definition |
|---|---|---|
| chromosome | cromosoma | A structure containing DNA with many genes |
| gene | gen | A segment of DNA that codes for a specific trait |
| allele | alelo | Different versions of the same gene (e.g., brown eye allele, blue eye allele) |
| dominant | dominante | An allele that shows its trait even with only one copy |
| recessive | recesivo | An allele that only shows its trait with two copies |
| genotype | genotipo | The actual alleles you have (BB, Bb, or bb) |
| phenotype | fenotipo | The trait you can see (brown eyes or blue eyes) |
Worked Example
Step-by-Step Problem Solving
Problem Scenario
Review the problem scenario and work through each step below.
Practice These Vocabulary Terms
WORKED EXAMPLE: Genetic Counseling Case (Week 5 - Advanced Integration)
Week 5+: YOU integrate concepts across multiple weeks independently!
PROBLEM:
A couple wants to know the probability that their children will have a genetic condition. The mother has brown eyes (Bb) and the father has blue eyes (bb). They also want to understand how this trait passed through the family across three generations. Use your knowledge from Weeks 1-5 to trace the inheritance pattern from DNA in cells β chromosomes β genes β observable traits.
YOUR TURN - Advanced Integration:
- Create a Punnett square for this cross and explain the probability of each phenotype
- Trace how this trait could have originated in the grandparents' generation (what were possible genotypes?)
- Connect to Week 3 (gene expression): Explain how the brown eye allele is expressed at the molecular level while the blue allele is "hidden"
AUTONOMY SUPPORT: Choose Your Learning Path (Week 5)
Research shows student choice increases engagement and deeper learning. Pick the approach that works best for YOU!
Option 1: Visual Pedigree Analysis
Trace genetic traits through family trees (pedigrees). Create a visual diagram showing how traits pass across 3 generations in a real or hypothetical family.
Best for: Visual learners who like diagrams and patterns
Option 2: Agricultural Breeding Simulation
Design a breeding program for crops or livestock. Use Punnett squares to predict outcomes over multiple generations to achieve desired traits (like disease resistance or high yield).
Best for: Applied learners who want real-world engineering applications
Option 3: Genetic Disorder Case Study
Investigate a real genetic condition (like cystic fibrosis or sickle cell anemia). Explain inheritance patterns, carrier probability, and why recessive conditions can "skip" generations.
Best for: Students interested in medicine and helping families understand genetic risks
Note: You can explore ANY of these approaches during stations or exit ticket reflections. Talk to Mr. Rosche if you want to dive deeper into one path!
Hook - The Sibling Similarity Mystery
12 Points | ~10 Minutes
The Challenge
What You'll Do (~10 minutes)
- Connect to prior knowledge about DNA and genes (3 min)
- Explore how traits pass from parents to children (4 min)
- Make predictions about inheritance patterns (3 min)
Think About This:
- Why do you look similar to your parents but not identical?
- How can siblings have the same parents but look different?
- What determines which traits you get?
COMPLETE THE HOOK FORM BELOW
Submit your prior knowledge and predictions before moving to Station 1.
[EMBED G7.C1.W5 Hook Form Here]
Form ID: ________________
Learning Support Tracker - Topic: Heredity
I do + You watch
We do together
You do + I check
Guided Practice (You Fill In):
"Chromosomes come in pairs because _____ [hint: think about parents]. For any gene, you might have _____ [hint: different versions from mom and dad]. This creates variation because _____ [hint: which version expresses?]. The CCC of Cause & Effect shows..."
Use this 4-step inheritance analysis:
- Identify the gene and its locations (alleles)
- Determine which allele is dominant
- Predict the phenotype (observable trait)
- Explain using cause-effect: genotype β phenotype
Station 1 - Chromosome Investigation
20 Points | ~15 Minutes
Your Mission: Understand Genetic Information Storage
Key Concepts:
- Chromosomes: Structures containing DNA with many genes
- Humans have 46 chromosomes arranged in 23 pairs
- Each pair: One chromosome from mom, one from dad
- Genes: Segments of DNA coding for specific traits
- Alleles: Different versions of the same gene
Investigation Focus:
- Why do chromosomes come in pairs?
- How do alleles relate to traits?
- Why does having two copies of each gene create variation?
INTERACTIVE: Chromosome Pairing Simulator
Explore all 23 pairs of human chromosomes. Click on any pair to see which genes are located there and the different alleles from mom (pink) and dad (blue).
Need extra support? Click here for hints and sentence starters
Key Concept Reminder:
- You got 23 chromosomes from mom and 23 from dad
- Each chromosome has the SAME genes in the SAME order as its partner
- But the alleles (versions) might be different!
Sentence Starters:
- "Chromosomes are in pairs because..."
- "A gene is like a recipe, and alleles are like..."
- "Having two copies creates variation because..."
Word Bank:
chromosome, gene, allele, DNA, trait, parent, offspring, version, copy, combination
Stuck? Click here for step-by-step help
Try these steps in order:
- Review: In Week 3 you learned that DNA is in the nucleus - chromosomes are how DNA is organized
- Analogy: Genes are like individual songs, chromosomes are like playlists
- Remember: 23 from mom + 23 from dad = 46 total chromosomes
- Watch: Search "Chromosomes and Genes"
- Still stuck? Email Mr. Rosche with your specific question
COMPLETE THE STATION 1 FORM BELOW
Explore chromosomes, genes, and alleles.
[EMBED G7.C1.W5 Station 1 Form Here]
Form ID: ________________
Station 2 - Trait Inheritance Patterns
20 Points | ~15 Minutes
Your Mission: Master Punnett Squares
Key Vocabulary:
| Term | Definition | Example |
|---|---|---|
| Dominant (B) | Shows trait with one copy | Brown eyes (capital letter) |
| Recessive (b) | Needs TWO copies to show | Blue eyes (lowercase letter) |
| Genotype | Actual alleles | BB, Bb, or bb |
| Phenotype | Observable trait | Brown eyes or blue eyes |
Common Misconception Alert!
Traits don't BLEND like mixing paint! A person with Bb has BROWN eyes (not medium-brown) because the dominant B is expressed. The b allele is still there but hidden.
Virtual Lab: Dominant & Recessive Alleles in Action
Use this PhET simulation to observe how dominant and recessive alleles are inherited across multiple generations. You'll see the same Punnett square logic you're practicing - but in a living population! Watch as brown fur (dominant) and white fur (recessive) alleles pass from parents to offspring.
Investigation Steps (8-10 minutes):
- Set Up Alleles: Start with a population that has BOTH brown fur alleles (dominant) and white fur alleles (recessive)
- Observe Inheritance: Click on individual bunnies to see their genotype (BB, Bb, or bb). Notice which phenotypes appear
- Track Ratios: Watch several generations. Do the phenotype ratios match Punnett square predictions? (3:1 ratio for dominant:recessive)
- Predict Outcomes: If a brown bunny (Bb) mates with a white bunny (bb), what genotypes will offspring have? Check your prediction!
- Homozygous vs Heterozygous: Find bunnies that are BB, Bb, and bb. Which ones show the brown phenotype?
Connection to Punnett Squares:
Every time two bunnies mate in the simulation, it's like filling out a Punnett square! The offspring genotypes follow the same probability patterns you calculate. If both parents are Bb Γ Bb, you should see approximately 25% BB, 50% Bb, and 25% bb in the offspring - just like your Punnett square predicts!
How to Use a Punnett Square:
- Draw a 2x2 grid
- Put one parent's alleles on top (B and b)
- Put other parent's alleles on the side (b and b)
- Fill in the boxes by combining top + side
- Count the outcomes: How many Bb? How many bb?
Need extra support? Click here for Punnett square help
Memory Tricks:
- Dominant = "Bossy" - it dominates over the recessive
- Capital letter = Dominant (B for Brown)
- Lowercase letter = Recessive (b for blue)
- Genotype = "Genetics" (what genes you have)
- Phenotype = "Physical" (what you look like)
Sentence Starters:
- "The genotype is _____ which means the phenotype is..."
- "If both parents are Bb, their children could be..."
- "The probability of blue eyes is _____ because..."
COMPLETE THE STATION 2 FORM BELOW
Practice Punnett squares and dominant/recessive patterns.
[EMBED G7.C1.W5 Station 2 Form Here]
Form ID: ________________
Station 3 - Design a Breeding Plan
25 Points | ~20 Minutes (Highest Value!)
Agricultural Engineering Challenge
Your Mission:
You are a plant breeder working with tomatoes. Design a breeding plan to achieve specific trait goals!
SCENARIO:
Traits:
- Red fruit (R) is DOMINANT over yellow fruit (r)
- Tall plants (T) is DOMINANT over short plants (t)
Client wants: YELLOW fruit on TALL plants
Available plants: Red/Tall (RrTt), Yellow/Short (rrtt)
Can you design a plan to achieve the goal?
Design Thinking Steps:
- Identify target genotype: What genes do you need? (rr for yellow, T_ for tall)
- Analyze crosses: What offspring can you get from available plants?
- Calculate probabilities: What fraction will have the desired traits?
- Plan strategy: Which plants to cross? Do you need multiple generations?
Need extra support? Click here for design hints
Design Tips:
- Break it down: Think about fruit color SEPARATELY from plant height
- For yellow fruit: You need rr (both recessive)
- For tall plant: You need at least one T (Tt or TT works)
- Target genotype: rrTt or rrTT
Sentence Starters:
- "First, I would cross _____ with _____ because..."
- "The offspring would have _____ genotype, which means..."
- "The probability of getting yellow/tall is _____ because..."
- "To identify the correct plants, I would look for..."
COMPLETE THE STATION 3 FORM BELOW
Design your breeding plan using genetic reasoning!
[EMBED G7.C1.W5 Station 3 Form Here]
Form ID: ________________
Exit Ticket - Heredity Basics Integration
23 Points | ~15 Minutes
Show What You Learned
Question Types:
- 2 NEW - Genes, alleles, and inheritance patterns
- 2 SPIRAL - Review of W3 gene expression and previous concepts
- 1 INTEGRATION - Apply Punnett squares to real-world genetics
- 1 SEP-2 - Using models (limitations of Punnett squares)
Remember:
Punnett squares help predict PROBABILITIES, not certainties. A 25% chance doesn't mean every 4th child will have that trait!
COMPLETE THE EXIT TICKET BELOW
This is your final assessment for Week 5. Take your time!
[EMBED G7.C1.W5 Exit Ticket Form Here]
Form ID: ________________
St. Louis's Growing Biotech Industry: From Genetics to Innovation
The heredity and genetics concepts you're mastering this week are driving St. Louis's growing biotech industry. Companies and research institutions at Washington University, the Cortex Innovation Community, and emerging biotech startups are developing genetic tests, gene therapies, and personalized medicine treatments based on understanding heredity. Genetic counselors help families understand inherited disease risks using Punnett square logic. Pharmacogenomicists predict how individuals will respond to medications based on their unique genotypes. Bioinformaticians analyze genetic data to discover new disease patterns and treatment targets. As St. Louis strengthens its position as a life sciences hub, there are growing opportunities for students who master the genetics you're learning nowβturning molecular knowledge into careers that transform human health.
Enrichment & Extension
Optional deep dives for early finishers.
Optional content if you finish early or want to go deeper.
Scientist Spotlight
Research a scientist who contributed to this week's topic area and describe their key findings.
Environmental Justice Connection
Explore how this week's science concepts connect to environmental justice issues in our community.