Unit Checkpoint: Cells
Test Your Knowledge
This checkpoint covers everything you've learned in the Cells unit. Answer all 10 questions to check your understanding. Click "Show Answer Explanation" after each question to learn more.
Question 1: What is the smallest unit of life?
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Correct Answer: B - Cell
The cell is the smallest unit of life. While atoms are smaller, they are not alive. Tissues and organs are made up of many cells working together. All living things are made of one or more cells.
Question 2: Which organelle is known as the "powerhouse" of the cell because it produces energy?
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Correct Answer: C - Mitochondria
Mitochondria convert food (glucose) into energy (ATP) that the cell can use. This is why they're called the "powerhouse" of the cell. Without mitochondria, cells wouldn't have the energy to perform their functions.
Question 3: Which structure is found in plant cells but NOT in animal cells?
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Correct Answer: C - Cell wall
Plant cells have a rigid cell wall made of cellulose that provides extra support and protection. Animal cells only have a flexible cell membrane. Both plant and animal cells have cell membranes, nuclei, and mitochondria.
Question 4: What is the function of chloroplasts in plant cells?
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Correct Answer: C - Make food through photosynthesis
Chloroplasts contain chlorophyll (the green pigment) and use sunlight, water, and carbon dioxide to make glucose (food) through photosynthesis. This is why plants can make their own food and animals cannot.
Question 5: Where is DNA located in a cell?
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Correct Answer: A - Nucleus
The nucleus contains DNA, which is the genetic material that has instructions for all cell activities. The nucleus is like the "brain" or "control center" of the cell because it directs what the cell does.
Question 6: Which type of graph would be BEST to show how a cell grows over 5 days?
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Correct Answer: B - Line graph
Line graphs are best for showing change over time. Since the question asks about growth over 5 days, a line graph would clearly show how the cell size changed from day to day. Bar graphs compare categories, and pie charts show parts of a whole.
Question 7: In a CER (Claim-Evidence-Reasoning) paragraph, what is the purpose of EVIDENCE?
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Correct Answer: B - To provide facts and data that support your claim
Evidence consists of facts, data, and observations that support your claim. Option A describes the claim, Option C describes reasoning. Good evidence comes from experiments, observations, or reliable sources.
Question 8: The jelly-like substance that fills the cell and surrounds the organelles is called the:
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Correct Answer: B - Cytoplasm
Cytoplasm is the jelly-like fluid that fills the cell between the cell membrane and the nucleus. All organelles float in the cytoplasm. It's like the "factory floor" where cell activities happen.
Question 9: Which organelle packages and ships proteins to where they are needed?
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Correct Answer: C - Golgi Body
The Golgi Body (or Golgi Apparatus) is like the "shipping and packaging department" of the cell. It takes proteins made by ribosomes, packages them, and sends them where they need to go inside or outside the cell.
Question 10: Why do plant cells typically appear more rectangular while animal cells appear more round?
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Correct Answer: B - Plant cells have a rigid cell wall that maintains their shape
The cell wall in plant cells is made of cellulose, which is rigid and provides structural support. This gives plant cells their boxy, rectangular shape. Animal cells only have a flexible cell membrane, so they can take on more irregular, rounded shapes.
Unit Summary
Cell Structure
Organelles and their functions
Plant vs Animal
Key differences between cell types
Data Analysis
Tables and graphs for cell data
CER Writing
Scientific explanations
Next Steps
- Review any questions you missed by reading the explanations
- Go back to specific lessons if you need more practice
- Continue to the next science unit to keep learning!