Answer:
Darwin proposed the theory of natural selection to explain the process of evolution. According to Darwin’s theory of natural selection, all organisms have the potential to reproduce limitlessly irrespective of the fact that each species maintain a constant density over time. However, the struggle for existence, i.e. the competition among individuals for available resources to survive and reproduce, put a check on species density (D) and maintains it at a constant level (B). Survival of fittest is unequal ability of individuals to survive and reproduce based on suitability of their inherited characters to prevailing environmental conditions (A). It imparts the reproductive advantage to certain organisms which account for major part of the gene pool of the species. Thus, natural selection favors the individual with survival and/or reproductive advantage over others under existing environmental condition (E). Thus, the correct answer is option C.
p = m / V (Density = Mass / Volume)
p = m / (w * l * h) (Density = Mass / [Width * length * height]) (V = w * l * h)
p = 120 / (5 * 4 * 3) (Mass = 120g [Given] w=5 l=4 h=3 [Given])
p = 120 / 60
p = 2 g/cm^3
Answer is B (2)
Answer:
In the 1960s, scientists found evidence that new material is indeed erupting along mid-ocean ridges. The scientists dived to the ocean floor in Alvin, a small submarine built to withstand the crushing pressures four kilometers down in the ocean. In a ridge’s central valley, Alvin’s crew found strange rocks shaped like pillows or like toothpaste squeezed from a tube. Such rocks form only when molten material hardens quickly after erupting under water. These rocks showed that molten material has erupted again and again along the mid-ocean ridge.
When scientists studied patterns in the rocks of the ocean floor, they found more support for sea-floor spreading. You read earlier that Earth behaves like a giant magnet, with a north pole and a south pole. Surprisingly, Earth’s magnetic poles have reversed themselves many times during Earth’s history. The last reversal happened 780,000 years ago. If the magnetic poles suddenly reversed themselves today, you would find that your compass needle points south.
Explanation:
I found this somewhere.
Sexual reproduction is a process involving the fusion of two gametes to
Gametes are special reproductive cells produced by meiosis. It produces genetically dissimilar offspring. Offspring may inherit beneficial qualities from both parents and there is a greater genetic variation in the offspring, leading to species that are better adapted to changes in the environment.