# Cells and Systems This worksheet reviews how living things are organized into cells, tissues, organs and systems, and how these parts work together to keep an organism healthy ([Topic](https://goa-cc-uat-aili-app-001.azurewebsites.net/explore/node/17317), [Outcome](https://goa-cc-uat-aili-app-001.azurewebsites.net/explore/node/17319)). You will also practise describing human body systems and the cells that make them function ([Outcome](https://goa-cc-uat-aili-app-001.azurewebsites.net/explore/node/17320), [Outcome](https://goa-cc-uat-aili-app-001.azurewebsites.net/explore/node/17321)). ## Exercises **1. Matching: Cell structures** Match each term to its correct description. Write the matching letter on the line beside each number. | Term | Answer | Description | |---|---|---| | 1. Cell membrane | ______ | A) Found only in plant cells, gives rigid support | | 2. Cell wall | ______ | B) Basic unit of life found in all organisms | | 3. Cell | ______ | C) Controls what enters and leaves the cell | **2. Short answer: Single-celled vs. multicelled organisms** Choose one single-celled organism and one multicelled organism (for example, an amoeba and a grizzly bear, or a single-celled alga and a poplar tree) ([Outcome](https://goa-cc-uat-aili-app-001.azurewebsites.net/explore/node/17320)). a) Name your two organisms: ______________________ and ______________________ b) Describe one similarity between them: ___________________________________________ c) Describe one difference between them: ___________________________________________ **3. Multiple choice: Diffusion and osmosis** Circle the best answer for each question. i) Diffusion is the movement of substances from an area of: A) low concentration to high concentration B) high concentration to low concentration C) equal concentration in all directions D) inside the cell only, never outside ii) Osmosis specifically refers to the movement of: A) oxygen B) water C) solid food particles D) electricity ([Outcome](https://goa-cc-uat-aili-app-001.azurewebsites.net/explore/node/17320)) **4. Fill in the blank: Human body systems** Use the words below to complete the sentences. Each word is used once. circulation digestion excretion respiration sensory a) The __________________ system breaks down food so the body can absorb nutrients. b) The __________________ system carries oxygen and nutrients to tissues through the blood. c) The __________________ system removes waste products from the body. d) The __________________ system brings oxygen into the body and removes carbon dioxide. e) The __________________ system allows the body to detect and respond to its surroundings. ([Outcome](https://goa-cc-uat-aili-app-001.azurewebsites.net/explore/node/17321)) **5. Short answer: Cells that keep the body healthy** For each cell type below, describe one job it does in the human body ([Outcome](https://goa-cc-uat-aili-app-001.azurewebsites.net/explore/node/17321)). a) Nerve cell: ___________________________________________________________________ b) Muscle cell: __________________________________________________________________ c) Blood cell: ___________________________________________________________________ **6. Extended response: Body response to change** Describe one way the human body changes its function in response to a changing condition. Choose one example: heart rate during exercise, metabolism in cold temperatures, or a reflex response to a stimulus ([Outcome](https://goa-cc-uat-aili-app-001.azurewebsites.net/explore/node/17321)). You may also mention one factor that could affect the healthy function of the system involved, such as illness, aging or air quality ([Outcome](https://goa-cc-uat-aili-app-001.azurewebsites.net/explore/node/17322)). Condition or stimulus: ____________________________________________________________ How the body responds: __________________________________________________________ _________________________________________________________________________________ A factor that could affect this system: ______________________________________________ _________________________________________________________________________________ ## Answer key 1. 1-C, 2-A, 3-B 2. Answers will vary. Similarity might note both are made of cells and carry out life functions; difference might note one is single-celled and one is multicelled, or differences in size and structure ([Outcome](https://goa-cc-uat-aili-app-001.azurewebsites.net/explore/node/17320)). 3. i) B, ii) B 4. a) digestion, b) circulation, c) excretion, d) respiration, e) sensory 5. Answers will vary. Nerve cells carry signals through the body; muscle cells contract to produce movement; blood cells carry oxygen, nutrients or fight infection ([Outcome](https://goa-cc-uat-aili-app-001.azurewebsites.net/explore/node/17321)). 6. Answers will vary. Example: heart rate increases during exercise to deliver more oxygen to muscles; illness or air quality could affect the respiratory system's healthy function ([Outcome](https://goa-cc-uat-aili-app-001.azurewebsites.net/explore/node/17321), [Outcome](https://goa-cc-uat-aili-app-001.azurewebsites.net/explore/node/17322)). --- *AILI homework sheet · language en · model claude-sonnet-5 · generated 2026-09-17 · id f9439806-0b68-47f0-b3a8-fe1db97b1a1e* ### Sources - node:n1: Unit B: Cells and Systems (https://goa-cc-uat-aili-app-001.azurewebsites.net/explore/node/17317) - node:n2: Outcomes for Science, Technology and Society (STS) and Knowledge (https://goa-cc-uat-aili-app-001.azurewebsites.net/explore/node/17318) - node:n3: *Students will:* Investigate living things; and identify and apply scientific ideas used to interpret their general stru (https://goa-cc-uat-aili-app-001.azurewebsites.net/explore/node/17319) - node:n4: *Students will:* Investigate and describe the role of cells within living things - describe the role of cells as a basic (https://goa-cc-uat-aili-app-001.azurewebsites.net/explore/node/17320) - node:n5: Students will: Interpret the healthy function of human body systems, and illustrate ways the body reacts to internal and (https://goa-cc-uat-aili-app-001.azurewebsites.net/explore/node/17321) - node:n6: *Students will:* Describe areas of scientific investigation leading to new knowledge about body systems and to new medic (https://goa-cc-uat-aili-app-001.azurewebsites.net/explore/node/17322)