By: Kat Centeno
An ecosystem is an ecological and biological environment where its members include plants, animals, sun, soil and water. The components in an ecosystem interact with each other for survival. The food chain is a complex representation of the producer-consumer relationship in an ecosystem. The energy...
Why viruses are referred to as obligate parasites
By: A.M. Yost
In biology, the term obligate refers to a species which is dependent on a specific niche or circumstance in order to survive. All viruses fit that description, along with a few bacteria. None can multiply or perform other functions outside of a host. Luckily...
Characteristics and habits of true toads (family Bufonidae)
By: M E Skeel
Warts and toads. They go together like witches and Halloween. The warts are actually glands that can produce secretions which are often poisonous or at least bad tasting to potential toad predators. There are other frogs that are called toads because of their warty appearance...
By: Norman Green
All plants require sunlight to grow. Plants can be grown under artificial lights, but these lights are just mimicking the effects of sunlight. Dependent on the type of plant and its natural habitat, the amount of sunlight required for healthy growth will vary, but no...
Tree profiles: Douglas fir
By: Rex Trulove
The Douglas fir, Pseudotsuga menziesii, is a mostly, but not entirely, western species of tree. Though it grows in many places, the most imposing examples are found in Northwest Oregon and Southwest Washington. In this area, these trees grow nearly as tall as the well-known...
By: Gene Patterson
Many people hear the word mutation and they have a brief flash of fear. Mutation! The word itself sounds scary. Certainly no one wants to be a mutant. But how about words like evolution and progress. That is what a mutant really is, simply genetics...
By: M E Skeel
Mutations are changes in the DNA. There are three main causes of mutations: duplication and transcription errors, damage to the DNA by chemicals, and damage by radiation. Although mutations can affect any cell in the body, it is mutations to sex cells, sperm and eggs...
By: Amelia Emery
The Noble Fir is one of the most beautiful conifers of the Pacific Northwest. Known botanically as Abies procera, it is native to the Cascade Mountain range and can be found in Washington, Oregon and northern California. It grows in the middle and upper elevations...
How insects use pheromones
By: Jackie Carroll
Put simply, pheromones are chemical messages between individuals of a species. They developed early in the history of life and are used by all sorts of animals, but they are particularly important to insects. With a few exceptions, pheromones are all made from the same...
Tuatara: Living dinosaurs in New Zealand
By: Terrence Aym
Most people grew up being taught that the mighty race of dinosaurs went extinct about 65 million years ago. But it's not true; dinosaurs still walk the Earth.No, it isn't a T-Rex or a living relative of the Loch Ness Monster…but it is...

 

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