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.
Answer:
Natural selection disrupts the genetic equilibrium by favoring the genes for the traits that impart survival advantage to individuals.
Explanation:
Natural selection refers to the unequal survival rate of individuals of a population due to the presence of some beneficial adaptive genetic trait. These individuals are able to survive more and leave more progeny. Over generations, the population has increased number of these individuals leading to evolution of a population with different allele frequencies.
For example, the frequency of gene for antibiotic resistance in the bacterial population was increased once humans started using antibiotics to control the bacterial population. This led to the evolution of the bacterial population with antibiotic resistance.
Before assessing the two given cases, an assumption needs to be made about the digestion of the two types of food items, corn and beef. Let us assume that both get digested by expending same amount of energy by the human body. Let the amount of energy at producer level be an arbitrary X.
Case 1: Corn to human:
Since corn is at the producer level, it will have X amount of energy. The transfer of energy from corn to human will take place with a loss of 90% energy at the producer level. Hence the humans will receive 10% of X amount of energy.
Case 2: Corn to cow to human:
Since corn has X amount of energy, only 10% will pass to the next level, i.e. cow. So cow has 10% of X. Cow transfers only 10% of the energy that it has. Hence humans receive only 10% of 10% of X amount of energy.
It can be seen that humans receive more energy in case 1 than case 2. Hence we can say that it is more efficient for humans to feed on corn.
Answer:
Image result for individual living thing
An organism is any individual living thing. It is easy to recognize a living thing, but not so easy to define it. Animals and plants are organisms, obviously. Organisms are a biotic, or living, part of the environment.
Reducing - buying digital books instead of paperback
Reusing- repairing broken toys, appliances and accessories
Recycling- disposing of paper products in bins labeled paper only
