Nutrition, Digestion and Excretion

Nutrition

Nutrition is acquiring the right category of food to ensure good health and growth. Nutrition is significant for growth and fitness of health because without good nutrition a person’s immune system gets weak. Nutrition defines an investigation of the choice of diets that people prefer, and presents the common diseases that poor nutrition cause. Poor nutrition is always linked with reduced fertility and the occurrence of malnutrition in the health of humans. Good nutrition consists of foods rich in minerals and vitamins, carbohydrates, roughages, proteins. Minerals include iron and calcium, which help the body control body fluids to and from body cells, develop strong bones and turn the consumed food to energy. Good nutrition includes dairy foods, cereals, fruits and vegetables, meat and fish. Carbohydrates provide starch to the body and they include rice, pasta, corn, potatoes, cassava and yams. Proteins help in the functioning, structure and regulation of body organs and tissues, and they include fish, beans, meant, eggs and milk. Roughages, on the other hand, do not add nutrients to food, but are essential in the proper functioning of the intestines. My diet is better than just to eat well plate diet, because it does not necessarily supply for my nutritional needs. Below is a table that shows my personal food diary.

Digestion

During absorption of food, different body parts are involved to ensure proper breakdown of food particles. The National Digestive Disease Information Clearinghouse argued that the stomach does not absorb food but contains enzymes that help break down food particles, such that nutrients can move down to the GI tract, which is the main area for absorption. The stomach only releases food to the small intestines after mixing and churning it slowly. Solid foods take longer than liquids to move from the stomach. The small intestine consists of jejunum, duodenum and ileum where absorption occurs. The duodenum takes in minerals, carbohydrates and proteins for absorption, while the remaining food particles in form of starch or proteins move to the jejunum. The ileum then absorbs fat, fat-soluble vitamins and amino acids. The large intestine consists of the rectum, cecum and colon. When food reaches the large intestines, full absorption takes place, and there are only waste products left. The colon absorbs the remaining sodium, potassium and water. Roughages, on the other hand, are not digestible, but add bulk to the large intestine, which help it to function properly. When digesting food, the pancreatic enzymes have digestive juice that is endohydrolase. The trypsin enzyme is always in its inactive form (trypsnogen), where the removal of hexapeptide activates it through the process of enterokinase of intestinal mucosa.

The Liver Functions

It is in the right upper side of the abdominal cavity at the top of the stomach and intestines. The liver has the shape of cone, weighs 3 pounds approximately and is reddish brown in color. It has two supply sources including the hepatic artery that transports oxygenated blood, and the hepatic portal vein that transports nutrient-rich blood. This organ is unique, because it can restore itself.  The liver has several functions, such as producing bile to help break down fats during digestion. This is through changing the levels of chemical and using the bile that carries all waste products from it. It produces proteins for the blood plasma, cholesterol to carry fats through the body and changes glucose to glycogen then later turns it to energy through the bile. In addition to this, this organ processes the iron content into the hemoglobin, regulates clotting of blood and removes bacteria from the bloodstream by processing the blood nutrients into simpler forms for the body. The by-products of the liver are moved to the blood or bile after it has removed bacteria in the bloodstream. The bile then releases the by-products into the intestine which releases them in form of waste or urine.

The Kidneys

The kidneys are located at the back of the abdomen and are approximately 5 inches long. Kidneys have one main function, which is to filter the blood that the body passes through them daily with the aid of nephrons. In addition to this, they ensure body fluids and electrolytes balance. During the filtration of blood in the body, the kidneys produce urine. They then pass the urine to structures in the shape of funnels that drain tubes to the ureters called the kidney pelvis.  Thereafter the urine is passed to the bladder, which releases it as poisonous waste. The kidneys if not well-cared for can cause several conditions in a person. Some of these conditions, such as infections on kidney pelvis and kidney stones are mild, while others, such as kidney cancer and kidney failure are severe. The kidney can only contain a small amount of fluids at the same time and so if there are more fluids in the body, they distribute it by releasing the waste fluids into the pelvis and leaving the nutrient-filled fluids in the body. This way, the body is able to release excess fluids for normal functioning. The kidney nephrons also help bring back potassium, sodium and phosphorus whenever the body runs low of them. Through the glomerulus and tubule in the nephrons, the kidney maintains the right amount of proteins in the blood.

In conclusion, nutrition, digestion and excretion all have things in common in that one process cannot be successful without the success of another. For example, with poor nutrition, body parts will not be able to function properly, hence lowering their excretion rate. Each internal body organ is responsible for ensuring proper functioning of another, because they work together.  From the digestive system to the excretion system, without proper diets to cater for good nutrition, the body organs are likely to fail in their functioning, because of a poor and weak immune system.