I.   Grade/Course Title: 7th Grade Science


      a. Course Overview/Description: ______________________________________________________


      b. Quarter: Four


II. Unit #6 LIFE SYSTEMS: BIOCHEMICAL    Unit Length 5 weeks


      a. Unit Introduction: The human body is a complex organism that is made up of a number of different body systems. Each system carries out a specific life process contributing to the body as a whole. The digestive, respiratory, and circulatory systems work in concert to provide our cells with nutrients and oxygen needed for energy production, growth, and repair. The digestive system breaks down food in the digestive tract into nutrients that can be transported by the circulatory system. The respiratory system provides oxygen from the air to the blood and returns the waste product carbon dioxide from the blood to the air. The circulatory system supplies the vital nutrients to all cells of the body.



      b. Standards for Unit #6

·      C 16. Describe the structures of the human digestive, respiratory and circulatory systems, and explain how they function to bring oxygen and nutrients to the cells and expel waste materials.

CT State Grade Level Expectations (Draft)

GRADE-LEVEL CONCEPT 2:  u  Multicellular organisms need specialized structures and systems to perform basic life functions.


1.       Systems consist of parts that interact with and influence each other.  Parts of a system work together to make the whole entity work.  Similarly, each part of an animal body has a specific job to do, and all the different parts work together to support life. 

2.       Although all cells have similar basic structures, in multicellular organisms cells have specialized shapes that enable them to perform specific roles (for example, muscle, nerve, and skin cells can be identified by their distinct shapes).

3.       Groups of similar cells are organized in tissues that have specific functions (for example, providing support, connecting parts, carrying messages, protecting internal and external surfaces).

4.       Different tissues work together to form an organ, and organs work together as organ systems to perform essential life functions.

5.       The major parts of the human respiratory system are the nose, trachea, bronchi and lungs. This system is responsible for breathing and exchange of gases between the body and its surroundings.

6.       The major parts of the human circulatory system are the heart, arteries, veins and capillaries.  The right side of the heart pumps blood to the lungs for gas exchange; the left side of the heart pumps the oxygenated blood around the body.

7.       The blood is made up of plasma, red and white blood cells, and platelets. Its main role is to carry small food molecules and respiratory gases (oxygen and carbon dioxide) to and from cells.  Blood cells are also responsible for destroying invading particles, preventing diseases, and stopping bleeding after injuries.

8.       The respiratory and circulatory systems work together to provide all cells with oxygen and nutrients.  When the body’s need for oxygen changes, the circulatory and respiratory systems respond by increasing or decreasing breathing and heart rates. These changes can be measured by counting breaths, heartbeats or pulses per minute.

9.       The major parts of the human digestive system are the mouth, esophagus, stomach, small intestine and large intestine. This system is responsible for breaking down food, absorbing nutrients and water, and eliminating waste.  The liver and pancreas support the functions of the major digestive organs by producing and releasing digestive liquids into the digestive tract. 

10.    The nervous, immune and excretory systems interact with the digestive, respiratory and circulatory systems to maintain the body’s dynamic internal balance (homeostasis).



c. Essential Questions:

1. How does the digestive system break down food?

2. How do different enzymes work on different foods?

3. How do nutrients enter the blood stream?

4. What are the components of the digestive system?

5. How do nutrients and oxygen enter the cell?

6. What are the components of the circulatory system?

7. How does blood move through the arteries and veins?

8 How is oxygen exchanged in the alveoli?


d. Essential Content/Concepts:

1.  The digestive system breaks down food that can be absorbed into the blood.

2. The digestive system consists of the digestive tract and the accessory organs.

3. Accessory organs produce digestive enzymes that are released into the digestive tract.

4.  The digestive system breaks down food by physical and chemical means.

5. The circulatory system transports needed nutrients to all body cells and carries away cell waste products.

 6. The components of the circulatory system are the heart, blood, arteries, veins, and capillaries.

7. The capillaries allow exchange between blood and cells in other tissues.

8. Blood is a liquid tissue that consists of plasma, red blood cells, white blood cells, and platelets.

9. The heart is a muscle that contracts regularly to pump blood throughout the body.

10. The respiratory system provides oxygen to the body.

11. The components of the respiratory are the trachea, bronchi, and air sacs.

12. Respiratory gases are exchanged in the alveoli.


e. Essential Skills:

1.  Identify major components of the circulatory, respiratory, and digestive system.

2.  Draw conclusions from data collected in an experiment.


f. Vocabulary

Digestive tract, esophagus, stomach, small intestines, large intestines, colon, accessory organs, enzymes, feces, heart, blood, plasma, red blood cells, white blood cells, platelets arteries, veins, capillaries, lymph, trachea, bronchi, alveoli,


g. Science Misconceptions

1. The difference in size between a cell and a molecule.

2. Blood is blue in color.

3. That the stomach is the only part of the digestive system.

4. That all digestion is mechanical.     





Trading Places


Travel Brochure of the Body Systems


Blood Bits



Reading For Information:

Chew For Health


IV.. Significant Tasks (ST): Feel The Beat

      a. Significant Task Introduction: In this investigation, students will explore how different movements (e.g., walking, climbing steps, lifting weights, or hand-clapping) affect pulse rate.  Students will also identify independent and dependent variables, and those variables that are kept constant, when designing an experiment. They will keep a detailed and organized record of your experimental design, data collection and analysis in their science notebook and draw conclusions and identify sources of error in the experimental process.




      b. Length/Timing: End of the unit


      c. Essential Questions:  

     Why does the heart beat faster with different movements?


      d. Assessment Tools (AT): Lab Report





            Readings, Texts, Materials, Videos


Suggested Science Fair Topics


Example Assessment Questions


  1. A group of organs working together to carry out a life process is called a(n)

a. cell      b. tissue       c. organ        d. organ system


  1. Going from the simple to complex, which order correctly represents the organization of the human body?
  1. organ system>organ>cell>tissue
  2. cell>tissue>organ>organ system
  3. tissue>cell>organ>organ system
  4. organ>organ system>cell>tissue


  1. The function of the circulatory system is to
  1. carry materials to and from the cells
  2. break down food into a usable form
  3. respond to stimuli
  4. regulate body activities


  1. Which represents the correct pathway of the nutrients in an apple once you take a bite?

a. circulatory system>cell>digestive system

b. digestive system>circulatory system>cell

c. cell>digestive system>circulatory system

d. circulatory system>digestive system>cell





  1. At each body cell,
  1. carbon dioxide enters the blood, and oxygen leaves the blood
  2. both carbon dioxide and oxygen enter the blood
  3. both carbon dioxide and oxygen leave the blood
  4. oxygen enters the blood and carbon dioxide leaves the blood


  1. The process by which energy is released from nutrients is called

a. cellular respiration   b. excretion   c. digestion     d. circulation


  1. What would happen if all of the red blood cells in your blood disappeared?





  1. How would the inability to make saliva affect digestion?






  1. Describe how the circulatory and respiratory system work together to provide nutrients to the cells.






10. What body process produces the carbon dioxide you exhale?