The human body is a remarkable network of human anatomy organs, each playing a specialized role to keep us alive and thriving. The term “organ” refers to a group of tissues that come together to perform unique functions. Although there are various ways to categorize human body parts, experts generally agree on a list of organs in the human body that totals seventy-eight. In this guide, we will uncover what are the 78 organs in the human body in order, identify the 5 vital organs of human body, explore how they function, and discuss fascinating extras that make our page more informative than ever.
An organ is formed when similar cells and tissues work together to perform a specific function. For example, your heart pumps blood, your lungs aid in respiration, and your liver supports digestion and detoxification. These internal organs of human body and their functions are vital for sustaining life. In fact, studying these structures helps us understand crucial concepts about our health and well-being.
Before diving into what are the 78 organs in the human body and their functions, let’s highlight the 5 vital organs of human body. These are absolutely critical for survival—if any one of these fails to function properly, life is at immediate risk without medical intervention.
Heart
Pumps blood throughout the body, supplying oxygen and nutrients.
Vital to circulatory health and maintaining blood pressure.
Brain
Central control system for thoughts, emotions, and body movements.
Regulates all voluntary and involuntary actions.
Lungs (Pair)
Facilitate the exchange of oxygen and carbon dioxide.
Essential for respiration and maintaining blood pH levels.
Liver
Largest internal organ and key for detoxification, bile production, and metabolism.
Helps in clotting and various biochemical processes.
Kidneys (Pair)
Filter out waste products and excess water from the blood.
Play a role in blood pressure regulation and maintaining electrolyte balance.
Explore, Human Respiratory System
Many learners often ask, “what are the 12 organs of the body?” or “what are the 78 organs in the human body in order?” The confusion arises because some sources focus on the major organs only, while others recognize additional structures such as glands, tissues, or newly classified organs (e.g., the interstitium). Below is a list of organs in the human body (in alphabetical order) recognized by most experts:
Note: Some items (like blood vessels) can be broken down further into arteries, veins, and capillaries. The exact counting may vary, but this remains the generally recognized list of organs in the human body.
Among these human body parts, a few stand out due to their size and overall impact. Learning about them sheds light on how complex our human anatomy organs truly are.
Skin (Largest External Organ)
Offers protection from pathogens, regulates temperature, and prevents dehydration.
Houses various sensory receptors for touch, temperature, and pain.
Liver (Largest Internal Organ)
Weighs around 1.3 to 1.5 kg.
Oversees hundreds of functions, including metabolism and detoxification.
Brain
Protected by the skull and cerebrospinal fluid.
Coordinates and regulates body functions, thoughts, and emotions.
Lungs
Spongy, elastic organs for gas exchange.
Expand and contract roughly 12-20 times per minute at rest in adults.
Heart
Pumps about 2,000 gallons of blood a day.
Always working, even as we sleep.
Also, read Structure of Brain
While all 78 human body parts name in the list have their importance, certain organs perform indispensable tasks:
Pancreas
Produces insulin, glucagon, and digestive enzymes.
Regulates blood sugar levels.
Small Intestine
Responsible for nutrient absorption.
Longest part of the alimentary canal.
Spleen
Filters blood, recycles old red blood cells, and supports immune function.
Stomach
Performs mechanical and chemical digestion.
Produces acid and enzymes for breaking down food.
Spinal Cord
Major conduit for transferring signals between the brain and the rest of the body.
Essential for reflex actions and coordination.
These internal organs of human body and their functions collectively keep your systems running in harmony.
Also, read Human Excretory System
Interstitium: Newly recognized by some researchers as a fluid-filled compartment that surrounds tissues.
Mesentery: Once thought to be just a fold of tissue, it’s now recognized as a continuous organ that supports and positions the intestines.
Such discoveries reflect how our understanding of human anatomy organs evolves with ongoing research.
Try this engaging activity to see how well you can identify key human body parts:
Gather some coloured stickers or markers.
Print or draw a simple outline of the human body.
Label at least 15 organs from the list of organs in the human body on your diagram.
Challenge a friend or family member to do the same. Compare your drawings and see who got more correct!
This hands-on task helps you remember human body parts name and placement in a fun way.
Which organ is responsible for filtering blood and removing waste products?
A. Pancreas
B. Kidneys
C. Heart
D. Lungs
The largest internal organ in the human body is:
A. Skin
B. Liver
C. Brain
D. Heart
Which organ produces insulin?
A. Thyroid
B. Adrenal gland
C. Pancreas
D. Pituitary gland
The fluid that cushions the brain is called:
A. Bile
B. Plasma
C. Synovial fluid
D. Cerebrospinal fluid
Lymph nodes are primarily associated with:
A. Digestion
B. Immune function
C. Respiration
D. Hormone regulation
Which of the following is part of the 5 vital organs of human body?
A. Spleen
B. Kidneys
C. Stomach
D. Pancreas
The alveoli are found in the:
A. Lungs
B. Liver
C. Brain
D. Stomach
The small tube carrying urine from the bladder to the outside of the body is called:
A. Ureter
B. Urethra
C. Trachea
D. Vas deferens
Which is the outermost covering that protects the entire body?
A. Skin
B. Hair follicles
C. Nails
D. Bone
The organ that helps in pumping blood is the:
A. Liver
B. Lungs
C. Heart
D. Kidneys
1 – B, 2 – B, 3 – C, 4 – D, 5 – B, 6 – B, 7 – A, 8 – B, 9 – A, 10 – C
1. How many organs are there in the human body?
There are commonly accepted to be 78 organs, though some sources may vary slightly depending on classification.
2. What are the 5 vital organs of human body?
The five vital organs are the heart, brain, lungs, liver, and kidneys. All are essential for survival.
3. Why do some sources say 12 organs?
“What are the 12 organs of the body?” often refers to the major organs or organ systems, but this number changes with different classifications.
4. Which organ is the largest in the body?
The skin is the largest external organ, whereas the liver is the largest internal organ.
5. Are blood vessels counted as organs?
Generally, arteries, veins, and capillaries are parts of the circulatory system, and some classifications count them individually as organs.
6. What is the interstitium?
The interstitium is a network of fluid-filled spaces newly recognized as a possible organ, surrounding tissues and organs.
7. How does the mesentery fit in the list of organs in the human body?
The mesentery was recently classified as an organ; it supports the intestines and holds them in place.
8. Is the appendix useless?
While often considered vestigial, research suggests the appendix may have immune functions, especially in gut flora maintenance.
9. Which organs are crucial in the digestive process?
The stomach, liver, pancreas, small intestine, and large intestine are key organs in digestion and nutrient absorption.
10. How do organs work together in the body?
Organs group into organ systems (e.g., respiratory, digestive, circulatory), ensuring different bodily functions are carried out in harmony.