Its renewed again and again by natural water cycle
Galapagos islands are groups of island in the pacific ocean that are known to have a wide range of native animals such as giant tortoise that found no where else on earth. These native animals helped Darwin in the development of the theory of natural significance which attributes to the biological significance of the Galapagos islands. Human species is a threat to the natural wildlife on these islands mainly due to poaching and destruction of natural forests that destroys habitat and also impacts negatively on biological diversity of living organisms.
All life depends on capturing energy from the sun and converting it in to a form that living organisms can use.
- Two key processes (mirror each other)
- Photosynthesis (Sun -> Plants)
<span>- Cellular respiration (Plants/Animals/energy)</span>
<span>Depletion of the ozone layer. Choloroflourocarbon (CFCS) are dangerous because of their destructive reaction with Ozone particles, which provide the Earth with a protective layer or shield against UV radiation. Depletion of the ozone layer begins when when CFC gets into the stratosphere. Sunlight breaks up cfcs releasing Chlorine Atom. Chlorine atoms in turn react with Ozone, starting a chemical cycle that destroys the ozone layer in that area. Once the ozone layer is depleted, there's nothing holding back the harmful UVB wavelengths of ultraviolet light (UV light) from passing through the Earth's atmosphere causing havoc on plants and animals.</span>
Answer: Positive feedback loop
Explanation:
Even before the food reaches the stomach (before ingesting it), the glands of the stomach mucosa begin to release its gastric secretion. The main characteristic of this secretion is acidity, as measured by pH (one of the physiological variables).
This acidity is a result of the presence of hydrochloric acid, which is part of the secretion composition. In addition to it, water, pepsinogen (which will give rise to the enzyme pepsin) and the intrinsic factor. The acid has a function of the protection of the entire system by eliminating microorganisms. It is also responsible for the activation of pepsin (which only occurs with acid pH), the enzyme that digests proteins containing the amino acids leucine or phenylalanine or tryptophan or tyrosine.
The concept of Positive feedback loop states that the body tries to increase the value of a variable (acidity, in the case of pepsinogen) when it is below its optimal value (called a point adjustment) and decreases this value when it is above optimal.