The differences between open and closed circulatory systems
By: Effie Moore Salem
Open and closed circulation In humans and in the higher animals, the pulmonary group of arteries and veins are a closed system within the overall system; the overall system being referred to as an open system. It is not an open system, however, when being...
The differences between open and closed circulatory systems
By: Trenna Sue Hiler
There are two basic types of circulatory systems in animals that require blood be pumped through the organism to deliver oxygen and remove waste. There is an open circulatory system and a closed circulatory system.In the most simple terms the closed system the blood...
By: Perry McCarney
All lifeforms need some method of moving substances around within themselves. Single-cell organisms use methods similar to those used by the cells of the multi-cellular, the natural spread of molecules from areas of high concentration, a process called diffusion, being a major one. Most...
How non-native species affect an ecosystem
By: Tiffany Aliano
Abstract The following article will briefly define what an ecosystem is as well as go into depth on how certain circumstances of changing factors within an environment can bring about devastating results. To further this discussion, this paper will describe two separate instances that...
By: Janet Grischy
Toxicity in plants is often a matter of application and degree. Many plant medicines derive from deadly poisons, and many medicines are poisons if overused. Poisons also have their uses in the world. Foxglove Digitalis, foxglove, grows in many gardens. Its tall spikes of purple...
Understanding pig behavior
By: Diane Jaramillo
Understanding pig behavior is certainly a lot easier than understanding human behavior. There are a lot of myths about pigs, ranging from their supposed lack of intelligence (not true) to the belief that they are filthy creatures (also not true). Let's examine some of those...
How to teach children about plants
By: Jose Plancarte
Teaching a child about plants can seem to be a daunting task at first, however, this is not the case. Children are naturally curious about the world that surrounds them. Do you remember how many questions you asked as a child? In fact, the best...
By: Lin Barrett
Are human beings still a part of nature? The last time you were ill, your body answered that question for you. The inevitable chemical processes ran their course, and in a few days you were fine again: but while you were ill, your body...
The link between human evolution and migration
By: Lin Barrett
Migration has, throughout human prehistory, both spurred and slowed human evolution. Prehistoric humans were hunter-gatherers. Dependent on the local flora for something approaching 70% of their total calories, they hunted for the remaining 30%. Fauna migrate as least as well as humans do, but flora...
Whales: How sound frequencies stored in DNA affect survival
By: Dr Ana Garcia Phd
Our emotional struggles are simply energy struggles; we use manipulation in our relationships in order to feed ourselves with other people's energies because we are disconnected from the source, the only place from where we can get unlimited energy supply, never-ending, never lacking; the only...

 

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