The element starts off as 100%. half of 100% is 50% and half of 50% is 25%. the element has emitted 2 times the half life which is 10,000 x 2 = 20,000
the fossil bone is 20,000 years old
Answer: b. causes the gastric glands to increase production of gastric juice.
Explanation:
The parasympathetic nerves are part of the autonomous nervous system. The parasympathetic predominates mainly during "passive responses" of the organism, such as satiety, rest and digestion. Its functions are: Promotes energy conservation, Reduces heart rate, Promotes glandular secretion, Protects the retina from excess light, Promotes emptying of cavities, Promotes rest and repair, Physiologically antagonizes sympathetic nervous system.
Answer:
Streak Test
Explanation:
A streak test is used by geologists to help determine the powdered color of a mineral. They usually use a white or black plate, scrape a sample of the mineral onto the plate, and voila!
P.S. I also had a question like this on a test before.
Answer:
In the cardinals, if the females start using a different criterion than the color of the feather when they choose couple, most likely to happen is that decreased variation in the shades of red because no form of the trait is advantageous.
Explanation:
Options for this question are:
- <em>Increased variation in the shades of red because the selection pressure has been relieved.</em>
- <em>Increased variation in the shades of red because the cardinals try different ways to impress the females.</em>
- <em>Decreased variation in the shades of red because no form of the trait is advantageous.</em>
- <em>Decreased variation in the shades of red because the only reason for variation was selection pressure.</em>
In the context of natural selection, male cardinals court females using the coloring of their feathers as a form of sexual selection. This means that the shades of red in the feathers are a selection criterion in these birds, and the more visible shades represent an advantage.
But, if the selection criterion was not the color of the feathers, this trait would no longer represent an advantage in the competition between the males to be chosen as a mate. Instead, the trait that would determine sexual selection would be the one that experiences an increase in its variation<em>.</em>
The correct answer is coevolution.
The term is used to illustrate the conditions where two or more species communally influence each other’s evolution. For example, an evolutionary modification in the morphology of a plant may influence the morphology of a herbivore that consumes it, this, in turn, may influence the evolution of the plant that might influence the evolution of the herbivore and so on.
Coevolution most possibly takes place when distinct species have a close ecological association with each other. These ecological associations include parasite/host and predator/prey, mutualistic species, and competitive species.
