Smaller arteries are more muscular in the structure of their walls. Nutrients may be organic or inorganic: Essential fatty acids EFAs are fatty acids that humans and other animals must ingest because the body requires them for good health but cannot synthesize them. Start the Quiz 0 of 10 questions complete Ready for Med School? There are a lot of other simple yet effective ways on how to keep the respiratory system healthy presented in the next part, so keep reading!
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The pharynx is responsible for the passing of masses of chewed food from the mouth to the esophagus. The pharynx also plays an important role in the respiratory system, as air from the nasal cavity passes through the pharynx on its way to the larynx and eventually the lungs. Because the pharynx serves two different functions, it contains a flap of tissue known as the epiglottis that acts as a switch to route food to the esophagus and air to the larynx.
It carries swallowed masses of chewed food along its length. At the inferior end of the esophagus is a muscular ring called the lower esophageal sphincter or cardiac sphincter. The function of this sphincter is to close of the end of the esophagus and trap food in the stomach. The stomach is a muscular sac that is located on the left side of the abdominal cavity, just inferior to the diaphragm.
In an average person, the stomach is about the size of their two fists placed next to each other. This major organ acts as a storage tank for food so that the body has time to digest large meals properly.
The stomach also contains hydrochloric acid and digestive enzymes that continue the digestion of food that began in the mouth. It is located just inferior to the stomach and takes up most of the space in the abdominal cavity. The entire small intestine is coiled like a hose and the inside surface is full of many ridges and folds. These folds are used to maximize the digestion of food and absorption of nutrients.
The liver is a roughly triangular accessory organ of the digestive system located to the right of the stomach, just inferior to the diaphragm and superior to the small intestine. The liver weighs about 3 pounds and is the second largest organ in the body. The liver has many different functions in the body, but the main function of the liver in digestion is the production of bile and its secretion into the small intestine. The gallbladder is a small, pear-shaped organ located just posterior to the liver.
The gallbladder is used to store and recycle excess bile from the small intestine so that it can be reused for the digestion of subsequent meals. The pancreas is a large gland located just inferior and posterior to the stomach. The pancreas secretes digestive enzymes into the small intestine to complete the chemical digestion of foods.
The large intestine is a long, thick tube about 2. It is located just inferior to the stomach and wraps around the superior and lateral border of the small intestine. The large intestine absorbs water and contains many symbiotic bacteria that aid in the breaking down of wastes to extract some small amounts of nutrients.
Feces in the large intestine exit the body through the anal canal. The digestive system is responsible for taking whole foods and turning them into energy and nutrients to allow the body to function, grow, and repair itself.
The six primary processes of the digestive system include:. The first function of the digestive system is ingestion, or the intake of food. The mouth is responsible for this function, as it is the orifice through which all food enters the body. The mouth and stomach are also responsible for the storage of food as it is waiting to be digested. This storage capacity allows the body to eat only a few times each day and to ingest more food than it can process at one time.
In the course of a day, the digestive system secretes around 7 liters of fluids. These fluids include saliva, mucus, hydrochloric acid, enzymes, and bile. Saliva moistens dry food and contains salivary amylase, a digestive enzyme that begins the digestion of carbohydrates.
Mucus serves as a protective barrier and lubricant inside of the GI tract. Hydrochloric acid helps to digest food chemically and protects the body by killing bacteria present in our food. The body has connectors neurons that communicate signals throughout the body. Messages are sent through nerves called neurons that are responsible for communication in the body. The nervous system controls the body's sense of smell, hearing, tasting, seeing and touching.
The brain is the largest function of the nervous system. The endocrine system is made from different glands in the body that are in charge of moving chemicals and hormones through the body.
Hormones control varies functions in the body such as growing, metabolism and moods. A gland is a bunch of cells that release chemicals. The endocrine system has an affect on nearly every cell, function and organ in the human body.
The respiratory system brings oxygen into the human body and gets rid of carbon dioxide. The body needs oxygen to live. The organ used in the respiratory system is the lungs.
Inside the lungs are tiny sacs. When the body takes in air, the lung sacs fill with air. The heart pumps blood inside the lungs and takes in oxygen and releases carbon dioxide. Every breath the body takes consists of taking in oxygen and releasing carbon dioxide.
Your Lungs and Respiratory System. The primary job of the circulatory system is transporting materials through the body. It carries nutrients, oxygen and water to different cells in the body and removes wastes the cells create. The main parts of the circulatory system are the heart, blood, and blood vessels.
The heart beats three billion times in an average life span and its primary goal is keeping the blood flowing through the body. The immune system is made up of cells, organs, proteins and tissues that fight together to guard the human body against diseases. The skin is an organ of the immune system that keeps harmful substances out of the body and holds beneficial substances in.
The immune system attacks germs and rids the body of disease. The body fights a common cold by producing more mucus through the mucous membranes which drain the germs out of the body. The digestive system helps turn food into a form that the body can find useful.
The nutrients that are taken into the body are distributed evenly by the circulatory system.