Clue 1: Orient yourself
What are the main parts, stages, or choices in this model?
Use the labels and the picture's left-to-right, near-to-far, or before-and-after order. Name only what you can point to.
The question
Two sides of the roof of the mouth touched. Why did they still fail to become one piece?
Why it matters: Joining the palate creates a working roof for the mouth. Understanding how its temporary seam clears helps explain later feeding, speech, and hearing needs when that joining step does not finish.
On your WebXam
You can sequence how two tissue edges join and compare ways a temporary seam is cleared.
For life
To find the cause, change one thing and watch what changes.
Principle: Same look, different cause
Try the everyday version first
Same look, different cause
Two zipper halves can touch without becoming one closed zipper. The teeth must line up, catch, and lose the temporary divider between them.
Do not jump to the biology yet. Treat the picture as a small system. Track its parts, follow one change at a time, and keep more than one explanation open until the picture supplies a way to separate them.
Clue 2: Trace one change
What changes while the other parts stay the same?
Follow one object, stage, or path. Point to the first place where the situation changes instead of jumping to the ending.
Clue 3: Keep the cause open
What check would separate two explanations that still fit the picture?
List more than one explanation that still fits. Name the extra observation that would help you separate those possibilities.
Now inspect the illustration
Work from the visible evidence. A useful answer names the part of the picture that supports it and leaves unknown causes open.
- 1What are the main parts, stages, or choices in this model?
- 2What changes while the other parts stay the same?
- 3What check would separate two explanations that still fit the picture?
Tier 1 check
Finish with the everyday model
Explain how two edges can touch but still fail to become one continuous piece.
Answer in plain words. You can finish this required check without opening either optional section below.
Ready for the real names? Optional tier 2
Craniofacial Research Track
Session 6The Master Switch, OctoberLens: Human Body Systems
When palatal shelves meet: the seam must disappear
Discovery question
Two sides of the roof of the mouth touched. Why did they still fail to become one piece?
Same look, different cause. Two seams can both disappear, even when the cells left in different ways, so the final picture does not reveal the full story.
Before this page, you should know
- Cell fate is the final identity a cell commits to, set by which genes it switches on.
- A is a that binds DNA and turns specific genes on or off.
If not, review
Today's new idea is only
Same look, different cause. Two seams can both disappear, even when the cells left in different ways, so the final picture does not reveal the full story.
Goal: Put the joining steps in order and compare two ways the temporary seam could be cleared.
Know by the end
- Two palatal shelves start beside the tongue, swing up to , and meet at the to form the secondary .
- Where the shelves touch, each is covered by a cell layer called the .
- The MEE must be removed, partly by (programmed cell death) and partly by EMT (-to-mesenchymal transition), so the shelves join into one continuous .
- The signaling tells the MEE to clear; without that signal the seam persists.
- The , a thin outer cell layer, must not stick where shelves should fuse, or it can block them from joining.
1
Rise and meet
Model start: Each starts hanging down beside the tongue, then rotates up to and reaches toward the .
- Draw the two palatal shelves before and after they swing up to .
- Mark the and the place where the two inner edges will touch.
2
Clearing the seam
Model start: The medial edge is the cell layer on the inner edge of each shelf, exactly where the two shelves press together.
- Define MEE and explain why it cannot simply stay in place.
- Compare and EMT as two ways the MEE cells are removed.
3
The signal and the failure point
Model start: is the signal that tells the medial edge to clear out so the shelves can fully join.
- State, in one line, what tells the MEE to do.
- Predict how a weak signal, or a that sticks, could leave Mateo with an open .
MedlinePlus
Open the tool Plain-language explanations of a gene or condition, written for patients and families.
When you use this: Use this when a research paper is too dense, or when you need to explain a finding to Mateo's family in everyday words.
What the screen looks like
Step by step
- 1Open medlineplus.gov/genetics and search the gene or condition (IRF6).
- 2Read the summary written in everyday words.
- 3Note the conditions the gene is linked to at the bottom of the page.
Capture these fields
- Topic: IRF6 gene
- Plain-language summary: IRF6 helps the tissues of the face join correctly before birth.
- Linked conditions: Van der Woude syndrome; nonsyndromic cleft
How to read it: Start here when a research paper is too dense. MedlinePlus gives you the gist in everyday words so you can go back to the harder source knowing what it is about.
Lost? About MedlinePlus Genetics
Level 1, Guided
Use the sentence starters, a word bank from the vocabulary, a labeled diagram, and the exact source link.
Level 2, Collaborative
Complete a partly blank model or table and explain it.
Level 3, Independent
Make a claim from a new example or an unfamiliar entry in the same database.
Team roles
- Manager: keeps the group moving
- Recorder: writes the shared model or table
- Evidence checker: verifies each claim against the source
- Reporter: explains the group's reasoning
Process reflection
- What evidence changed your thinking today?
- What did your group disagree about, and how did you resolve it?
- What question is still unresolved?
By the end of this session, submit ONE of: a labeled diagram with a 2-sentence explanation; a claim, evidence, reasoning paragraph; a completed data table from a real database; or a one-question exit ticket using today's vocabulary.
Meets standard if your explanation correctly connects structure, timing, gene or protein function, or evidence source to Mateo's case: Put the joining steps in order and compare two ways the temporary seam could be cleared.
How this is graded (rubric)
For: Put the joining steps in order and compare two ways the temporary seam could be cleared.
| Criterion | Proficient | Developing | Beginning |
|---|---|---|---|
| Complete | Every required part of the artifact is present and filled in. | Most parts are present, but one is missing or left blank. | Several parts are missing. |
| Accurate | The science and data are correct and match the evidence. | Mostly correct, with a small factual slip. | Key science or data is wrong. |
| Scientific reasoning (CER) | States a claim, backs it with specific evidence, and explains the reasoning. | Has a claim and evidence, but the reasoning is thin or missing. | Gives an answer with no evidence or reasoning. |
| Professional communication | Clear, organized, and labeled the way a clinician or scientist would write it. | Readable but disorganized or missing labels. | Hard to follow. |
| Submitted | Turned in through the route named under Submit here and confirmed. | Turned in, but in the wrong place or unconfirmed. | Not turned in. |
How the model answer scores against this rubric
- CompleteProficient: Nothing is left blank: the model fills every part of "Put the joining steps in order and compare two ways the temporary seam could be cleared.".
- AccurateProficient: Every number and claim matches the case evidence.
- Scientific reasoning (CER)Proficient: It names a claim, cites the specific evidence, and explains the reasoning, not just the answer.
- Professional communicationProficient: It is organized and labeled like a real chart note.
- SubmittedProficient: It would be attached to your class form or handed in, and confirmed.
Go deeper Optional tier 3
Everything required is above. Open this section only if you want the research reading and source trail.
Student reading
The idea in plain English
Two sides of the roof of the mouth touched. Why did they still fail to become one piece?
Two zipper halves can touch without becoming one closed zipper. The teeth must line up, catch, and lose the temporary divider between them.
Same look, different cause. Two seams can both disappear, even when the cells left in different ways, so the final picture does not reveal the full story.
- Two palatal shelves start beside the tongue, swing up to , and meet at the to form the secondary .
- Where the shelves touch, each is covered by a cell layer called the .
- The MEE must be removed, partly by (programmed cell death) and partly by EMT (-to-mesenchymal transition), so the shelves join into one continuous .
- The signaling tells the MEE to clear; without that signal the seam persists.
- The , a thin outer cell layer, must not stick where shelves should fuse, or it can block them from joining.
This lesson reading is written from the vetted sources in the advanced citation trail below.
Everything you need for today is on this page. These links are optional.
What to read
Read the short plain-language explanation written for this lesson. Plain-language reading for this session
Why this source matters
This explanation gives you the background for today's idea without making you decode a research paper: Same look, different cause. Two seams can both disappear, even when the cells left in different ways, so the final picture does not reveal the full story.
Reading moves
- Skim the title and abstract first to get the gist.
- Circle the one sentence that states the main claim.
- Box the evidence the authors give for that claim.
- Mark one sentence that confuses you, and move on.
Stop point
Stop after the final 'Use it now' section. The research citations are available separately for advanced readers.
Your output
Write one claim-evidence sentence: state the main idea, then name the example or evidence that supports it.
These records and papers document the science. They are not assigned student reading. Use the plain-language lesson reading above unless your teacher asks you to inspect an original source.