Answer:
External factors include physical and chemical signals. Growth factors are proteins that stimulate cell division. – Most mammal cells form a single layer in a culture dish and stop dividing once they touch other cells.
Explanation:
From Google
Answer:
This is due to the event of Speciation that happened for the rodents in Island B but not for the rodents in Island C.
Explanation:
- Due to splitting of the population,
- The sub-population of rodents formed in Island B are B1 and B2.
- The sub-population of rodents formed in Island C are C1 and C2.
- In case of Island B, each of the B1 and B2 sub-populations that got split from each other developed certain mutations that were necessary for them to adapt to the particular diverse environment each of them were exposed to, through the period of 50,000 years. These mutations were so varied that reproductive isolation was generated between them that resulted in each of them to develop into different species.Hence, speciation happens here and B1 and B2 are incapable of inter-breeding.
- In case of Island C, each of the C1 and C2 sub-populations that got split might have got exposed to similar environmental change or no environmental change or the environmental change might have been too small to cause drastic change in each of the sub-populations. As a result of this the two sub-populations might have acquired certain mutations to adapt to the environment each of them were exposed to, through a period of 100,000 years. These mutations might not have been too variable or contrasting to cause reproductive isolation between C1 and C2. Hence, no new speciation happens here and C1 and C2 are capable of inter-breeding.
Animals cause erosion in other ways too. When too many animals live in one place, they tend to eat and trample all the plants. Without the plants to protect the soil, it is much more likely to be eroded by wind and water. Animals cause weathering and erosion on rocky shorelines.
Answer:
the first option is correct
Explanation:
in a food pyramid the base is always producers.
