OBJECTIVE LIFE SCIENCE
EVOLUTION
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Question
[CLICK ON ANY CHOICE TO KNOW THE RIGHT ANSWER]
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so that their babies can have friends to play with
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the more offspring the more likely the offspring will survive
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the more offspring the less likely offspring will survive
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the more offspring the less competition
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Detailed explanation-1: -As the chance of fertilization is nature dependant i.e it depends on the movement of water for the sperm to come in contact with the egg. Thus the fish and frog produce a huge number of eggs each year to overcome the chance factor(sperm to come in contact with egg) and produce offsprings.
Detailed explanation-2: -Generally, the number of eggs laid is strictly proportional to the likelihood of mortality of the offspring. So to maximise the survival rate, frogs create a lot of gametes.
Detailed explanation-3: -Compared to hens, fish and frogs lay hundreds of eggs because:-In Fish and Frogs, external fertilization occurs.-In the external medium (water), the male releases a large number of gametes while the female parent lays a large number of eggs.
Detailed explanation-4: -In most species of frogs, fertilization is external. The male frog grabs the female’s back and fertilizes the eggs as the female frog releases them (Figure 2.2B). Rana pipiens usually lays around 2500 eggs, while the bullfrog, Rana catesbiana, can lay as many as 20, 000.
Detailed explanation-5: -As fertilization takes place in the water it is external ferlitization. There is no safety for the fertilized eggs in the water so these animals lay more number of eggs. Whereas cow and human beings usually give birth to only one at a time and the internal fertilization takes place in these animals.