Parts of body systems and their functions

Category: Topics in the syllabus

The body is made up of many systems that all work together as a unit. Each body system has a particular function. Let’s see their functions and parts.

Digestive system
Function: The digestive system takes nutrients from the food and turns it into energy.
Parts

1. Mouth. The mouth chews and breaks the food down into small pieces to be digested.​
   • Teeth. The teeth chop the food into small pieces.
   • Tongue. The tongue rolls and moves the food in the mouth.
   • Salivary glands. The saliva moistens and lubricates the food.
2. Pharynx. The pharynx receives the food from the mouth when you swallow.
3. Esophagus. The esophagus delivers food to the stomach.
4. Stomach. The stomach digests the food with a mixture of digestive enzymes and acid.
5. Small intestine. The small intestine absorbs the nutrients from the food.
6. Pancreas. The pancreas secretes digestive enzymes into the small intestine.
7. Liver. The liver processes the nutrients from the small intestine and secretes the bile for the digestive process. It also filters toxins from the blood.
8. Gallbladder. The gallbladder stores and recycles excess bile.
9. Large intestine. The large intestine absorbs water and breaks down waste.
10. Rectum. The rectum holds the stool (fecal matter) until it is evacuated.
11. Anus. The anus controls the expulsion of the feces.

 
Respiratory system
Function: The respiratory system provides oxygen to all body’s cell and gets rid of carbon dioxide.
Parts

1. Nose and nasal cavity. The nose and the nasal cavity inhale and filter air entering the body.
2. Pharynx. The pharynx ensures that air can pass into the trachea.
3. Larynx. The larynx prevents food or drinks from being aspirated in the respiratory tract.
4. Trachea. The trachea filters the air before it goes to the bronchi.
5. Bronchus. The bronchus connects the trachea to the lungs.
6. Lungs. The lungs provide oxygen to all body’s cell and exhale carbon dioxide.
7. Alveolus. The alveolus exchange carbon dioxide for oxygen.
8. Diaphragm. The diaphragm contracts and relaxes the thoracic cavity in order to let the air moves into and out of the lungs.

 
Circulatory system
Function: The circulatory system transports blood and oxygen from the lungs to all body’s cells.
Parts

1. Heart. The heart pumps the blood to the different parts of the body.
2. Arteries. The arteries carry oxygenated blood to organs and cells in the body.
3. Veins. The veins carry deoxygenated blood from parts of the body back to the heart.
4. Blood. The blood carries water, oxygen, nutrients, and waste products to and from the body’s cells.
5. Lungs. The lungs send oxygen-rich blood to the left side of the heart.

 
Nervous system
Function: The nervous system sends signals from the brain to the rest of the body.
Parts

1. Brain. The brain receives input from the sensory organs, interprets that information, and guides the response to it.
2. Spinal cord. The spinal cord relays information to and from the brain.
3. Nerves. The nerves carry signals from the body to the spinal cord or brain.

 
Skeletal system
Function: The skeletal system gives the body structure, provides motor power for the movement, protects organs, stores minerals, and produces red blood cells.
Parts

1. Skull. The skull protects the brain.
2. Clavicle. The clavicle provides support and movement of the arms.
3. Ribs. The ribs protect the lungs.
4. Radius. The radius enables the hand to rotate and be flexible.
5. Phalanges. The phalanges give the movement of the fingers and toes.
6. Vertebral column. The vertebral column protects the spinal cord.
7. Pelvis. The pelvis allows movement of the body, especially walking, running, sitting, and kneeling.
8. Femur. The femur transmits forces from the tibia to the hip joint.
9. Tibia. The tibia supports the movement of the leg.

 
Muscular system
Function: The muscular system helps the body move and gives it shape, heat, and strength.
Parts

1. Heart. The heart pumps the blood to the different parts of the body.
2. Triceps. The triceps extend the elbow and straighten the arm.
3. Biceps. The biceps help the arm to bend at the elbow.
4. Abs. The abdominal muscles provide postural support and protect internal organs.
5. Quadriceps. The quadriceps give movement of the knee.

 
Excretory system
Function: The excretory system eliminates the body’s waste.
Parts

1. Kidney. The kidneys filter extra water and toxins such as urea from the blood.
2. Liver. The liver filters toxins from the blood.
3. Large intestine. The large intestine breaks down waste.
4. Skin. The skin excretes sweat through sweat glands throughout the body.
5. Lungs. The lungs get rid of the carbon dioxide.
6. Ureter. The ureter carries urine from the kidney to the urinary bladder.
7. Urinary bladder. The urinary bladder collects waste excreted by the kidneys.
8. Urethra. The urethra excretes the urine out of the body.

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