How Much Do You Know About How Your Organs Work?


By: Kristin Tolentino

6 Min Quiz

Image: Yuichiro Chino / Moment / Getty Images

About This Quiz

When you think about it, your organs do some pretty amazing stuff. For starters, they help you breathe and think every single day. Your organs also digest all of your favorite foods, whether you're munching on veggies or sipping a fruit smoothie. Needless to say, your organs work very hard. But do you know how they actually work?

Well, thanks to this challenging quiz, you can finally find test your anatomy knowledge. We'll ask you about the functions and roles of different organs. We'll also discuss the ways organs interact with other parts of the body. Last but not least, we'll talk about entire organ systems and how they keep you healthy and well.

If you are nervous about taking this quiz, don't worry. Just liver little and trust your gut! If you get stuck, you can always click the "hint" button. By doing so, you'll get a nudge in the right direction. So, whether you work in the medical field or simply love science, you can be sure that you'll have fun with this quiz. You might even learn something new along the way, too.

Ready to find out if you know how your organs work? Let's get this quiz started.

Which part of the brain controls body temperature, hunger and thirst?

The hypothalamus is in charge of basic bodily functions. Aside from body temperature, hunger and thirst, it also controls sleep, growth, weight and more. The hypothalamus is small, but important!


The gallbladder stores something that's produced by the liver. Do you know what it's called?

Bile is a fluid that helps your small intestine digest lipids like cholesterol, fats and fat-soluble vitamins. The fluid, which is sticky and thick, ranges from dark green to yellow-brown in color.


So, you just ate tasty lunch. How does your stomach break down the food?

Your stomach produces a liquid called gastric acid. It's made of sodium chloride, potassium chloride and hydrochloric acid. After this fluid breaks down the food, it moves on to your small intestine.


What organ delivers blood and nutrients throughout your body?

Your heart pumps blood to various parts of the body. This is super important because blood is rich in nutrients and oxygen! So, when your organs get enough blood, they can work properly and stay healthy.


Did you know that your lungs aren't the same size? Which one is bigger?

Your right lung is slightly bigger than your left lung. This because your heart is on the left side of your body, and it takes up a lot of space. So, your left lung is smaller, which gives the heart more room.


What's another name for the large intestine?

The large intestine is also known as the colon or large bowel. When digested material reaches this organ, existing bacteria breaks it down. This becomes waste, which is eventually excreted as stool.


The muscles in your intestines move food by contracting and relaxing. What is the movement called?

When food and liquid pass through your intestines, the muscles move in a wave-like movement called peristalsis. Your esophagus also uses peristalsis to move food to your stomach.


Can a human live without a spleen?

Yes, you can live without a spleen! Your spleen, which is like a large lymph node, filters the blood. But if you need to have your spleen removed, the liver and lymph nodes can get the job done.


Which part of the brain controls emotions like fear or anxiety?

The amygdala controls your emotional reactions. For example, if you have a fear of spiders, you can thank your amygdala! It tells the rest of your brain that something is a threat.


The heart uses multiple chambers to pump blood. How many does it have?

The human heart has four chambers. They're called the right atrium, right ventricle, left atrium and left ventricle. Together, these chambers pump blood throughout the body.


What organ regulates your blood sugar levels?

The pancreas is located just behind the stomach. It regulates your levels of blood sugar, which is also known as blood glucose. This organ also secretes digestive enzymes into the small intestine.


Which of the following functions isn't done by the liver?

The liver makes bile, which is stored by the gallbladder. It also filters blood and removes toxins as your body processes food and medicine. But when it comes to taking in oxygen, your lungs are the organs for the job.


Your lungs are made of tiny air sacs. What are these air sacs called?

Your lungs have approximately 600 million tiny air sacs called alveoli. They're in charge of letting oxygen pass into your blood, which then brings oxygen to different parts of your body.


What organ system includes the airways, larynx and lungs?

The respiratory system helps you breathe. With every breath, it takes in oxygen and gets rid of carbon dioxide. This is important because your entire body needs oxygen to function.


Do you know what's the most complex organ in your body?

From thinking to feeling, your brain controls everything you do and say. It's also responsible for memory, movement and decision making. Luckily, it's protected by a thick skull.


Which organ is in charge of making urine?

The kidneys are bean-shaped organs that are part of the excretory system. They filter the blood and remove toxins, which eventually become urine. This helps the body maintain fluid balance.


A community of bacteria lives in your digestive tracts. What is it called?

The microbial community in your intestines is called gut flora or gut microbiota. These "good" bacteria help digestion, control metabolism and work with your immune system to keep you healthy.


Which two gases are exchanged in your lungs?

During gas exchange, your lungs deliver oxygen to the blood. At the same time, your lungs pull out carbon dioxide from your blood. The carbon dioxide leaves your body when you exhale.


What is the largest organ in the body?

Your skin is your largest organ! It also grows the fastest. As an organ that protects your body, skin keeps all of your inside parts in place. It also keeps out harmful germs so you can stay healthy.


In order to make urine, what do your kidneys need to filter?

Every day, your kidneys filter almost 3 liters of blood about 60 times. As blood passes through, the kidneys pull out waste and excess water, which eventually becomes urine.


Which organ consists of the duodenum, jejunum and ileum?

In the small intestine, the duodenum secretes a fluid that neutralizes stomach acid. The jejunum absorbs nutrients into the bloodstream, while the ileum absorbs bile acids, vitamin B12 and other remaining nutrients.


When you're faced with a threat, which gland triggers a "fight or flight" response?

When your brain senses fear, it sends signals to your adrenal glands. These glands release adrenaline, which increase your heart rate and send blood to your muscles. This response helps you get away in the face of danger.


What's the outermost layer of your skin called?

The epidermis is basically a barrier. As the outermost layer, it keeps out harmful germs that can cause infection. The inner layers of the skin are called the dermis and hypodermis.


Do you know what a nephron is? Which organ is it part of?

Nephrons are the filtering units of your kidneys. One kidney has about one million nephrons! They filter your blood and make urine, which is sent to your bladder.


What organ system includes the adrenal gland, thyroid gland and pineal gland?

The endocrine system consists of glands that produce important hormones. For example, the pineal gland releases melatonin, a hormone that controls your sleep.


You just ate a delicious sandwich. Where are most of the nutrients absorbed?

When you eat food, most of nutrient absorption takes place in the small intestine. A lot of this happens in the jejunum, the middle section of the small intestine.


What kidney-shaped organs help the immune system?

Lymph nodes, or lymph glands, are part of the lymphatic system. They support the immune system by filtering foreign substances and cancer cells. You have lymph nodes all throughout your body.


Which sensory organ lets you detect light and colors?

Your eyes are organs that respond to light and pressure. When they absorb light, our brain processes the information and forms visual images. Your eyeballs are able to move because of different eye muscles.


This organ produces eggs and releases hormones that control menstruation. What is it called?

Ovaries are female reproductive organs; there's one on each side of the body. Each month, they make an egg for fertilization. The ovaries also release hormones that regulate the menstrual cycle.


Which organ system sends chemical signals to and from your brain?

Your nervous system includes your brain, spinal cord and sensory organs (like your skin and eyes). These parts are connected by nerves that send chemical messages in the form of electrical signals.


Males have organs that make sperm. What are these organs called?

Testicles are two egg-shaped organs that are responsible for making sperm. They also produce testosterone, the primary male sex hormone. Testicles are also known as testes.


After your kidneys make urine, where does the urine go?

The bladder stores urine until you go to the bathroom to pee. When it's empty, the bladder is about the size of a grapefruit, but it can stretch if needed.


Which organ system includes the liver, stomach and intestines?

Thanks to your digestive system, your body can break down food and absorb nutrients. It also turns your food into energy, which is essential for basic bodily functions.


Your body can make cholesterol. Which organ is in charge of this?

Cholesterol gets a bad reputation, but you do need some of it to survive. In fact, it's so important that your liver makes it for you! Your small intestine also makes a small amount.


Which of the following isn't a hollow organ?

The liver is a solid organ. However, the stomach, large intestines and heart are like empty bags or tubes. This lets things like food or blood move through.


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