Rough draft.This research track is under review with Dr. Atit's lab. Content and sequence may still change.
Craniofacial Research Track
Session 6The Master Switch, OctoberLens: Human Body Systems
When palatal shelves meet: the seam must disappear
Discovery question
Mateo's palatal shelves did grow and rise, but the roof of his mouth stayed open. If the shelves touched, what step at the seam between them did not finish?
Rising and touching is not enough. The cell layer at the inner edge of each shelf must be cleared so the two shelves become one , with no seam left behind.
The plan
Prerequisite check
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
Rising and touching is not enough. The cell layer at the inner edge of each shelf must be cleared so the two shelves become one , with no seam left behind.
Learn first
What to learn
Goal: Describe how palatal shelves rise and meet, and explain how the medial edge is removed by and EMT under the signal so the seam disappears.
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.
The plan
Guided notes
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 .
Explore
Reading the Research
What to read
Read the title and the abstract only, not the whole paper. Development of the face and palate (open textbook)
Why this source matters
This is the published evidence behind today's idea: Rising and touching is not enough. The cell layer at the inner edge of each shelf must be cleared so the two shelves become one , with no seam left behind.
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
You do not need the methods or statistics yet. If a sentence is about lab technique or math you have not learned, mark it and skip it.
Your output
Write one claim-evidence sentence: what this source claims, and the one piece of evidence that backs it up.
Explore
Vetted links for this session
Learn first
Pick your level
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.
The plan
Work as a research team
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?
Check yourself
Demonstration of learning
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: Describe how palatal shelves rise and meet, and explain how the medial edge epithelium is removed by apoptosis and EMT under the signal TGFB3 so the seam disappears.
How this is graded (rubric)
For: Describe how palatal shelves rise and meet, and explain how the medial edge epithelium is removed by apoptosis and EMT under the signal TGFB3 so the seam disappears.
| 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 the right way (Schoology for routine work) 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 "Describe how palatal shelves rise and meet, and explain how the medial edge epithelium is removed by apoptosis and EMT under the signal TGFB3 so the seam disappears.".
- 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 turned in on Schoology and confirmed.