Answer: This is a positive feedback loop.
Explanation:
The protein digestion in the body is an example of the positive feedback. The gastric secretions is stimulated chiefly by the action of three chemicals.
These chemicals are acetylcholine, histamin and gastrin. These chemicals stimulate the parietal cells to secrete HCL and intrinsic factors.
The chief cells secrete pepsinogen in response to the gastrin and ACh. As the dietary proteins are digested, it breaks down the amino acids and peptides.
This stimulates the G cells of the stomach to secrete more gastrin. This is how the positive feedback loop for the protein digestion works.
Answer:
On his visit to the Galapagos Islands, Charles Darwin discovered several species of finches that varied from island to island, which helped him to develop his theory of natural selection.
Darwin's finches are a classical example of an adaptive radiation. Their common ancestor arrived on the Galapagos about two million years ago. During the time that has passed the Darwin's finches have evolved into 15 recognized species differing in body size, beak shape, song and feeding behaviour.
Answer:
The homogeneous mixture is only in the one phase of matter, whereas heterogeneous mixture is always in two or more than two different phases of matter. Solutions are termed as the homogeneous mixtures, on the other hand, suspensions or colloids are termed as the heterogeneous mixtures.
Examples:
Homogeneous:
Bronze: this alloy is an example of homogeneous substances since it is composed of tin and copper.
Milk : this mixture that we see in a uniform way is composed of substances such as water and fats.
Heterogeneous:
Mixtures in two or more phases are heterogeneous mixtures. Examples include ice cubes in a drink, sand and water, and salt and oil. The liquid that is immiscible form heterogeneous mixtures. A good example is a mixture of oil and water.
