Why is Digestion Necessary?
Digestion is a necessary life process because it absorbs needed nutrients from food and gives energy to the cells of the body. Without digestion we would not have the energy in our cells to grow, maintain homeostasis and carry out other necessary life functions. In humans, nutrients such as proteins, carbohydrates, lipids and amino acids are absorbed in the small intestine. On the walls of the small intestine are small hair like structures called villi that absorb and diffuse nutrients into the blood stream where it takes it to the cells. Cellular respiration is the process in which the chemical energy stored in a sugar called glucose is used to make ATP. ATP is the energy all organisms use for movement. Digestion breaks up large molecules like starch into glucose to make ATP.
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A Great Blue Heron's Diet
Great Blue Heron Digestion
The neck, beak and legs of a Great Blue Heron allow them to be amazing hunters. A special vertebrae in their necks which create an "s" shape allow them to snap their necks deep into water or in the air to catch their prey at lighting fast speeds. Their razor sharp beaks allow them to stab their prey, especially fish, to stop them and kill them quickly and efficiently before swallowing them whole. Their long legs allow them to wade in deeper water to catch more fish, insects and frogs without as much effort.
Birds have higher metabolic rates than humans which means they can digest faster. Most birds and herons in particular have a loose digestive tract. Herons do not have crops, which is most birds are sacs used to contain a meal for it is digested. Herons instead just sallow their meals down their flexible esophagus's and into their loose and stretchable stomachs. [1] Heron stomachs are so flexible that they are able to stretch down and even past the cloaca. Herons also do not have gizzards which are in most other birds and help break down tougher parts of the food like bones. Like in humans, the pancreas and the liver release bile and insulin and glucagon. Bile breaks down lipids. Insulin and glucagon regulate blood sugar levels. Herons also absorb nutrients from their food in the intestinal villi. In carnivores, such as the Great Blue the small intestine is shorter and less coiled then in non- meat eating birds.
Birds have higher metabolic rates than humans which means they can digest faster. Most birds and herons in particular have a loose digestive tract. Herons do not have crops, which is most birds are sacs used to contain a meal for it is digested. Herons instead just sallow their meals down their flexible esophagus's and into their loose and stretchable stomachs. [1] Heron stomachs are so flexible that they are able to stretch down and even past the cloaca. Herons also do not have gizzards which are in most other birds and help break down tougher parts of the food like bones. Like in humans, the pancreas and the liver release bile and insulin and glucagon. Bile breaks down lipids. Insulin and glucagon regulate blood sugar levels. Herons also absorb nutrients from their food in the intestinal villi. In carnivores, such as the Great Blue the small intestine is shorter and less coiled then in non- meat eating birds.