Cell Structure and Function: From Molecule to Organelle

Cell Structure and Function: From Molecule to Organelle

Grade 10 · Science · NYSSLS HS-LS1-1 · 60 Minutes

NYS-Aligned Standard

HS-LS1-1 — Construct an explanation based on evidence for how the structure of DNA determines the structure of proteins which carry out the essential functions of life through systems of specialized cells. NYS P-12 Science Learning Standards / NYSSLS (2017)

Three-Dimensional Alignment

Learning Objectives — “I Can” Statements

• I can trace the pathway from DNA → RNA → protein (central dogma).
• I can explain how a protein’s shape determines its function (enzyme, structural, transport).
• I can construct a written explanation of how a mutation in DNA can alter protein function.
• I can connect specific cell functions to the specialized cells that perform them.

Essential Question

How does the information stored in DNA become the machinery that keeps you alive?

Lesson Sequence

Hook (8 min)

1. Present: “Sickle cell disease is caused by a change of ONE letter in the DNA code — changing a single amino acid in hemoglobin. How can ONE change affect an entire blood cell’s shape?”
2. Students write a hypothesis (2 min), share (2 min). Bridge: “Today we’ll explain exactly how that happens.”

Direct Instruction (18 min)

1. Central Dogma: DNA → mRNA (transcription) → protein (translation)
   • DNA is in the nucleus; mRNA travels to the ribosome; ribosome assembles amino acids
2. Protein structure: sequence of amino acids determines shape; shape determines function
3. Types of proteins: enzymes (speed up reactions), structural (collagen, keratin), transport (hemoglobin), signaling (hormones)
4. Mutation → altered protein → altered (or lost) function → disease or altered cell behavior

Guided Practice (15 min)

1. In pairs: read an original case study (below) about a hypothetical enzyme
2. Identify: (a) what the DNA codes for, (b) what the protein does, (c) what happens when the DNA mutates
3. Share out; class builds a cause-effect chain on the board

Original Case Study (StandardCraft-authored):

Enzyme L is a protein produced by cells in the pancreas. Its job is to break down fats during digestion. Enzyme L has a specific active site shaped to bind fat molecules. When a mutation occurs in the gene that codes for Enzyme L, the active site changes shape and can no longer bind fat. As a result, fats pass through the digestive system undigested. This leads to nutrient absorption problems.

Independent Practice (12 min)

Students write a 4–6 sentence explanation responding to: “Using evidence from today’s lesson and the case study, explain how DNA structure determines protein structure, and how that protein structure determines cell function. Include one specific example.”

Closure (7 min)

Exit ticket: “Trace the pathway from a change in DNA sequence to an observable change in a cell’s function. Use the central dogma.”

SDI & Differentiation Block

Supports for MLLs/ELLs

Entering/Emerging (NYSESLAT Levels 1–2):

• Central Dogma visual flowchart: DNA → RNA → Protein (arrow diagram with bilingual labels)
• Case study vocabulary pre-taught: enzyme, active site, mutation, protein, function
• Allow bullet-point format for the written explanation instead of full paragraphs
• Sentence frame: “DNA codes for ___. The protein ___ does ___. When DNA mutates, ___ changes because ___.”

Transitioning/Expanding (NYSESLAT Levels 3–4):

• Provide a partially completed explanation template with sentence starters
• Academic vocabulary preview: transcription, translation, amino acid, sequence, mutation, active site
• Allow student to speak through explanation before writing

Supports for Students with IEPs

SDI Adaptation Dimensions: content, methodology, delivery

• Content: Focus on the central dogma as a 3-step sequence only; reduce the explanation to 2–3 sentences using a graphic organizer; remove mutation analysis if prerequisite content is not in place
• Methodology: Use a color-coded central dogma flowchart (blue = DNA, green = RNA, orange = protein); provide the case study with key evidence sentences highlighted
• Delivery: Allow typed or dictated response; extended time; graphic organizer with fill-in structure provided

Suggested Placement: ICT

Suggested IEP Goal Reference (Teacher Reference Only — Not Legal Advice): Given a central dogma flowchart and a case study with highlighted key sentences, the student will write a 2-sentence explanation connecting DNA structure to protein function with 75% accuracy across 4 of 5 assessment tasks, supporting progress toward HS-LS1-1.

Extensions for Advanced Learners

• Research a specific genetic disease (sickle cell, PKU) and trace the exact DNA change to the altered protein to the phenotypic result
• Connect to NYSSLS HS-LS3-1: chromosome structure and gene expression
• Evaluate: Why is the central dogma called a “dogma”? Is it truly a rule without exceptions? (Hint: retroviruses)

Answer Key / Model Written Explanation

“DNA stores genetic information in the sequence of its nitrogenous bases. Through transcription, this information is copied into mRNA, which then travels to the ribosome. In translation, the ribosome reads the mRNA code and assembles a specific sequence of amino acids. This sequence folds into a protein with a particular three-dimensional shape, and that shape determines what the protein can do (its function). In the case of Enzyme L, a mutation changes the shape of the active site, preventing fat binding and disrupting digestion — demonstrating that even a small change in DNA can cascade into a significant change in cellular function.”

Alignment Record