Explanation:
The large size of a egg makes it difficult for the female to retain more than a single one egg at a time - carrying eggs would make flying harder and require more energy. (Bird eggs vary in size from the tiny 0.2 gramme eggs of hummingbirds to the enormous 9 kilogram eggs of the extinct elephant bird.)
Just as an aircraft cannot fly if it is overweight, all female birds must dispense with the fertile egg as soon as it is formed. And because the egg is such a protein-rich high-nuitrition prize to all sorts of predators, birds must find a secure place to hatch their eggs. Although birds' eggs appear to be fragile, they are in fact extremely robust. The oval shape applies the same rules of engineering as an arched bridge; the convex surface can withstand considerable pressure without breaking. This is essential if the egg is not to crack under the weight of the sitting bird. It takes 26 pounds of pressure to break a swan's egg and 120 pounds to smash the egg of an ostrich.
Answer:
comparing the effects of exercise intensity
The correct answer is - underwater mountain ranges.
The mid-ocean ridges are actually underwater mountain ranges, which usually are very long, in fact the longest mountain range on Earth is created on the divergent boundary between the Eurasian and North American tectonic plates and between the African and South American tectonic plates. At the divergent tectonic boundaries we have the creation of new crust which rises from the mantle and fills in the gap between the tectonic plates. Because of the big amount of magma and high pressure, very big and long underwater mountain ranges are formed.
Answer: The alleles of a plant that is heterozygous for seed color can be represented as Y for dominant allele for yellow seed and y for recessive allele for green seed.
Explanation: A plant that is heterozygous for seed colour has one dominant allele and one recessive allele for seed colour. If Y represents the dominant allele for yellow seed colour and y represents the recessive allele for green seed colour, therefore the plant has a genotype of Yy. A dominant allele is one that has the ability to mask the effect of a recessive allele while a recessive allele is one whose effect is masked by a dominant allele. Dominant alleles are denoted with upper cases while recessive alleles are denoted with lower cases. A plant that is heterozygous for seed colour with genotype Yy will manifest outwardly as Yellow seed colour due to the presence of the dominant allele Y.
Answer:
i think it is the middle one
B