When the concentration gradient of such molecules is high on the either the cytoplasmic side or the extracellular side of the cell. When the concentration gradient is high it flows freely through the cell membrane to the other side without expanding energy.
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Cane Toads are very strong and adaptable, they are also poisonous throughout its life cycle, which is why they only have a few predators and have a life span of 10-15 years. Cane toads have poison glands, and the tadpoles are extremely toxic to most animals if consumed. They are productive breeders, they only need a small pool of water of almost any nature. The female cane toads can lay 8,000 to 35,000 eggs at a time and may produce two clutches in one year. The eggs will hatch within 24-72 hours and the tadpole stage may last from three to twenty weeks. Cane toads in the tropics grow really quick and may be sexually mature only within one year. Cane toads have been introduced to many regions of the Pacific and the Caribbean islands as a method of agricultural pest control because of their ravenous appetite, however, they are now considered pests and are dangerous to humans and animals, both wild and domesticated especially to dogs.
Letter A. This is true it is caused from bacteria on the skin.
By the term "condensed", this refers to the density of a state of matter. As a rule of thumb, solids are the most dense because their molecules are very close together. Next is liquids because they flow compared to solids. The least dense are gases. Therefore, a change from a more condensed state to a less condensed state is boiling (liquid to gas).