Answer: The correct answer is -
D) giraffes having increasingly longer necks over time.
Natural selection is an evolutionary mechanism that was proposed by Darwin.
According to this mechanism, organisms that are better capable of adapting to their changing environmental conditions, survive and increase their number through reproduction whereas other are eliminated from the population.
Example - Long neck of Giraffe, which is much elongated, lofty stature, that was beautifully adapted for browsing on the higher tree branches. This was an adaptation with slow and gradual change in the gene frequency as the lower vegetation was eaten by other animals. Due to this, giraffes had to search for other source (that was higher tree branches).
This is considered as a peculiar example of natural selection.
Answer:
B
Explanation:
"Energy is generated in a red dwarf in the same way that it is in the Sun, namely through the fusion of hydrogen into helium. ... So long is the process, in fact, that the lifespan of a red dwarf can be far longer than the expected age of the universe, thought to be about 14 billion years."
Answer:
Hormones are the body's chemical messengers. They carry information and instructions from one set of cells to another. The endocrine system influences almost every cell, organ, and function in the body.
The correct answer is True.
TEMPERATURE: Although enzymes are also affected by the pH and the concentration of the enzyme and substrate in their environment, this specific example shows that enzymes are affected by temperature.