THE IMPORTANCE OF DIGESTION
In general, animals ingest their food as large, complex molecules that must be broken down into smaller molecules. These smaller molecules can then be absorbed by the blood. The digestive system does just that, using a series of specialized organs that comprise what we call 'digestion'. Without the digestive system, animals would be unable to process food or gain energy or nutrients from food. In humans, the digestive system will break food down into three main groups: carbohydrates, proteins, and vitamins.
Take, for example, a ham and cheese sandwich. The bread is made up of carbohydrates and starches. It undergoes digestion the moment it enters the mouth. The bread continue to be broken down with the digestive juices in the pancreas, and the nutrients finally diffuse into the blood stream from the small intestine. However, starch produces something very important to the human body: glucose. Glucose is used to make energy in the human body, but first it must undergo an operation known as cellular respiration. Cellular respiration is a complicated chemical formula which essentially takes glucose and oxygen and creates energy, or ATP, carbon dioxide, and water. The energy in ATP can be used in the cell as a power source to drive various types of chemical and mechanical activities.
Take, for example, a ham and cheese sandwich. The bread is made up of carbohydrates and starches. It undergoes digestion the moment it enters the mouth. The bread continue to be broken down with the digestive juices in the pancreas, and the nutrients finally diffuse into the blood stream from the small intestine. However, starch produces something very important to the human body: glucose. Glucose is used to make energy in the human body, but first it must undergo an operation known as cellular respiration. Cellular respiration is a complicated chemical formula which essentially takes glucose and oxygen and creates energy, or ATP, carbon dioxide, and water. The energy in ATP can be used in the cell as a power source to drive various types of chemical and mechanical activities.
thorny oyster digestive system and obtaining food
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Before the digestion of the Atlantic Thorny Oyster can be discussed, it must first be understood how this organism obtains food. In the case of this organism, the anatomy of the digestive system and how it gets its next meal are closely related. The Spondylus Americanus, like all bivalves, is a filter feeder. [1] This means that it feeds by straining suspended particles in the water. To filter feed, they beat their thousands of cilia and make water enter their gills through their current siphon, and expel the water out their excurrent siphon. While the water is in the mantle both the cilia and mucus on the gills catch food particles and move them to the mouth.[2] From the mouth, food moves through the esophagus into the stomach where extracellular digestion takes place. Extracellular digestion means "outside-of-shell digestion": enzymes are secreted through the cell membrane onto the food. The enzymes break down the food into smaller molecules. Then from the stomach the food moves into the animals intestine, which passes through the heart, and is where food is intracellularly digested. The waste then moves from the intestine to the anus where it is removed from the body.
Spondylus Diet
The Atlantic Thorny Oyster, through its filter feeding process, picks up several types of food. It's main food sources come from organic matter that falls onto the ocean floor, or microscopic organisms. Phytoplankton, detritus, and even zooplankton are a common part of the Spondylus Americanus' diet. It has been a common belief that feeding is an automated and mechanical process, but there have been recent studies done that show bivalve species have the ability to recognize filtration and select particles based on their size, shape, nutritive value or chemical component on the surface of the particle. [4] The slideshow below shows the different types of food this organism will eat.