In this audio resource from NOVA, astronaut Gene Cernan recounts his harrowing experience during America's first attempt to do work in outer space.

The digestive system is amazing: it takes the foods we eat and breaks them into smaller components that our body can use for energy, cell repair and growth. This lesson introduces students to the main parts of the digestive system and how they interact. In addition, students learn about some of the challenges astronauts face when trying to eat in outer space.

The Engineering and the Human Body unit covers the broad spectrum of topics that make-up our very amazing human body. Students are introduced to the space environment and learn the major differences between the environment on Earth and that of outer space. The engineering challenges that arise because of these discrepancies are also discussed. Then, students dive into the different components that make up the human body: muscles, bones and joints, the digestive and circulatory systems, the nervous and endocrine systems, the urinary system, the respiratory system, and finally the immune system. Students learn about the different types of muscles in the human body and the effects of microgravity on muscles. Also, they learn about the skeleton, the number of and types of bones in the body, and how outer space affects astronauts' bones. In the lessons on the digestive, circulatory, nervous and endocrine systems, students learn how these vital system work and the challenges faced by astronauts whose systems are impacted by spaceflight. And lastly, advances in engineering technology are discussed through the lessons on the urinary, respiratory and immune systems while students learn how these systems work with all the other body components to help keep the human body healthy.

This lesson describes the major components and functions of the immune system and the role of engineers in keeping the body healthy (e.g., vaccinations and antibiotics, among other things). This lesson also discusses how an astronaut's immune system is suppressed during spaceflight due to stress and other environmental factors.

This lesson describes how the circulatory system works, including the heart, blood vessels and blood. Students learn about the chambers and valves of the heart, the difference between veins and arteries, and the different components of blood. This lesson also covers the technology engineers have developed to repair the heart if it is damaged. Students also understand how the circulatory system is affected during spaceflight (e.g., astronauts lose muscle in their heart during space travel).

This lesson helps students explore the functions of the kidney and its place in the urinary system. Students learn how engineers design instruments to help people when kidneys are not functioning properly or when environmental conditions change, such as kidney function in space.

Students are introduced to the International Space Station (ISS) with information about its structure, operation and key experiments. The ISS itself is an experiment in international cooperation to explore the potential for humans to live in space. The space station features state-of-the-art science and engineering laboratories to conduct research in medicine, materials and fundamental science to benefit people on Earth as well as people who will live in space in the future.

Students learn about the unique challenges astronauts face while eating in outer space. They explore different food choices and food packaging. Students learn about the engineering design process, and then, as NASA engineering teams, they design and build original model devices to help astronauts eat in a microgravity environment --- their own creative devices for food storage and meal preparation.

This lesson covers the topic of muscles. Students learn about the three different types of muscles in the human body and the effects of microgravity on muscles. Students also learn how astronauts need to exercise in order to lessen muscle atrophy in space. Students discover what types of equipment engineers design to help the astronauts exercise while in space.

This activity helps students learn about the three different types of muscles and how outer space affects astronauts' muscles. They will discover how important it is for astronauts to get adequate exercise both on Earth and in outer space. Also, through the design of their own microgravity exercise machine, students learn about the exercise machines that engineers design specifically for astronaut use.

This lesson describes the function and components of the human nervous system. It helps students understand the purpose of our brain, spinal cord, nerves and the five senses. How the nervous system is affected during spaceflight is also discussed in this lesson.

This lesson goes over the parts of the human respiratory system and the gas exchange process that occurs in the lungs. It also covers changes in the respiratory system that occur during spaceflight, such as decreased lung capacity.

Students learn how the endocrine system works and compare it to the mail delivery system. Students discuss the importance of communication in human body systems and relate that to engineering and astronauts.

In this activity, students participate in a series of timed relay races using their skeletal muscles. The compare the movement of skeletal muscle and relate how engineers help astronauts exercise skeletal muscles in space.