Answer:
mutualism and parasitism
Examples:
mutualism: crocodiles and birds
parasitism: mosquitoes and humans
A zygote is immediately formed after fertilization between two gametes. This cell is eukaryotic and made up of a combination of the DNA in both gamete. Zygote contains all the hereditary information essential in the formation of a new individual.
The more numbers of the homologous structure, the more likely they have recently shared a common ancestor.
Explanation:
Homologous organs are defined as those organs which do have different functions but a similar basic structure which denotes the divergent evolution. Homologous organs are seen in species that are very close to each other which are more related with each other in terms of evolution. For example, a bird is more close to each man than a fish, so do share more homologous organs common to man than fishes do. Examples of the homologous organs are hands of human and wings of birds. They have same basic structure like skeletal structure which is humerus, radius, ulna, carpals, metacarpals and phalanges. They are similar in structure but have different functions like flying in birds and gathering food in humans.
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.
