Answer:
After 6000 years, approximately 500 atoms of carbon-14 will be left in the femur bone of an animal which had 1000 atoms of carbon-14 when the animal died.
Explanation:
The half-life of a radioactive isotope of an element is the time taken for half the atoms present in a given amount of the element to undergo decay or disintegration. For example, the half-life of carbon-14 isotope is 5730 years. This means that, if there are 100 atoms of carbon-14 present in a given sample of a material, in the next 5730 years, approximately, 50 atoms of carbon-14 will be left in the material.
Since the half-life of radioactive isotopes are constant, these radioactive isotopes are used in the determining the ages of ancient life-forms as well as rocks.
In the given example, after 6000 years, approximately 500 atoms of carbon-14 will be left in the femur bone of an animal which had 1000 atoms of carbon-14 when the animal died.
1. C
2.B
3.C
4. A
5. False
6.True
7.False
8.True
9.True
10. false
Hopefully this help
Answer:
The correct answer is: The ventromedial hypothalamus plays a role in satiety.
Explanation:
The hypothalamus is a part of the brain that controls many important bodily functions and connects both the nervous system with the endocrine system. The hypothalamus consists of several nuclei that have diverse functions and are located in 3 different regions.
The nucleus that plays a role in satiety is the ventromedial nucleus, terminating hunger and giving a sensation of fullness. It also plays a significant role in thermoregulation, among other things.
Neuropeptide Y, on the other hand, is a peptide that is released to make us feel hungry and encourage us to intake food (primarily carbohydrates).
Cholecystokinin is a hormone released by the small intestines after we had a meal, and its function is to improve digestion and make us feel full.
Fat cells DO release leptin, but the function of this hormone is to produce satiety, by stimulating anorexigenic (meaning they take hunger away) hormones and inhibiting orexigenic ones, like Neuropeptide Y.
The answer is C. Producers make food which os then consumed then decomposers eat the remains.
The answer is 4. Hope this helps