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This content has been developed to support nursing students preparing for the National Council Licensing Examination for Registered Nurses (NCLEX-RN). Videos and questions will be added to this collection throughout the summer and fall of 2014. All of this content has been created under the direction of Khan Academy and has been reviewed under the direction of the the American Association of Colleges of Nursing (AACN). This content is intended to be a supplemental resource for nursing graduates, not a program of study for the NCLEX-RN exam. The NCLEX-RN is administered by the National Council of State Boards of Nursing (NCSBN). For more information on the NCLEX-RN, visit: https://www.ncsbn.org/nclex.htm
Community Questions

NCLEX-RN Practice Questions

A collection of NCLEX-RN questions from all the diseases covered in the NCLEX-RN test prep section.

Circulatory system

Your heart sits in the middle of your chest and pumps blood from about 4 weeks after conception until the day that you die. It never stops, and over your lifetime it will pump ~175 million liters of blood. To visualize that, imagine the amount of water that falls over Niagara falls in a few minutes. Remarkable! This little pump is the size of your clenched fist and in an adult can weigh about 300 grams. Watch these videos to learn more about how the heart works, blood flow in arteries and veins, blood pressure, and lymphatics.

Circulatory system diseases

With the heart pumping 24 hours a day, 7 days a week, it’s absolutely vital to make sure things are flowing smoothly (pun intended!). Unfortunately, this isn’t always the case, and different parts of the circulatory system can cause problems: your heart, your blood vessels, and even the fluid in your tissues and blood itself can be the issue. To further complicate things, the underlying reasons for circulatory system problems vary from your genes (nature) to your lifestyle habits (nurture). An understanding of how different diseases can affect your circulatory system is important to combat this growing problem in the world.

Respiratory system

Place your hand on your ribs and inhale deeply. You’ll notice that your chest expands and your back straightens. As this occurs, air is rushing through your windpipe and branches off to either your left or right lung. After 20 to 30 more branch points, oxygen in the air ends up in the alveoli where it diffuses into the liquid that surrounds the alveoli, and slips into the blood. This microscopic gas exchange occurs rapidly, oxygen is taken into the body and carbon dioxide is removed from the body, and then you exhale. Learn more about the intricate and fascinating respiratory system in these videos!

Respiratory system diseases

Our lungs are composed of a bronchial tree (think of an upside down tree with millions of leaves), blood vessels bringing blood in and out, and a protein-rich fluid that forms a matrix holding everything together! If any part of this well-balanced organ isn’t working properly, a person can be left feeling short of breath. The lungs are also exposed to the outside environment, making them prone to infections. To counter infections, the lungs are lined with cells that have tiny protein bristles which wave back and forth and can literally sweep away dangerous bacteria. Learn more about diseases of the lungs and how modern medicine helps to keep them healthy!

Hematologic system diseases

Blood is incredibly important in combating disease and the healing process after an injury. It acts as a highway for medicine, stops bleeding, fights infections, controls cells from multiplying too fast, and so much more. But things can go wrong with blood too! What if your blood couldn’t clot and stop you from bleeding, or started to clot uncontrollably? What if your red blood cells or white blood cells suddenly disappeared? Blood contains many different types of tissues doing very different jobs, making diseases of the blood produce a variety of symptoms, including continuously feeling tired and bone pain. Learn about the different blood diseases, how they are diagnosed, and the cool ways health professionals treat these conditions.

Endocrine system

Dive into the endocrine system! See how the body uses special organs (called glands) that secrete chemical messages (called hormones) in order to properly respond to it's changing environment.

Lymphatic system

Welcome to the lymphatic system! Learn about how it is a critical part of the circulatory system. Find out how it comes to the rescue of the cardiovascular system and the immune system. Also discover how it moves fluid in one direction, like blood, but without a heart!

Immune system

Discover your body's arsenal of weapons against invaders, like bacteria and viruses. Find out which different kinds of cells are involved, and how they work.

Renal system

Learn how the kidneys take blood and very selectively extract waste from it to expel from the body as urine. Learn how the kidneys vary our salt and water content to regulate our blood pressure.

Gastrointestinal system

Understand how we digest food from the second it enters our mouth to the moment it ends up in the bathroom. Learn how the Gastrointestinal Tract is perfectly designed to digest food and extract nutrients for our bodies to use.

Muscular system

How do our muscles work? When we decide to kick a ball or shake a leg, how do we get our bodies to do that? Which muscles do we control? Which muscles control us? Learn how our muscles work at the smallest, most cellular level. Then see how nature scales up those microscopic processes into a kick or a dance move. Finally, learn how our brain tells muscle to contract and how that helps us respond to changes in temperature or even a lion chasing us.

Skeletal system

The skeletal system plays numerous vital roles in the human body. Learn about the structure and function of bones and the skeleton, as well as the endocrine control of the skeletal system.