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:
d. it diffuses into mitochondria to be broken down to generate ATP
Explanation:
When enough oxygen is available in the muscle cells, pyruvate produced by glycolysis enters the mitochondrial matrix. Once inside the mitochondria, pyruvate is decarboxylated into acetyl CoA. The reaction is catalyzed by the enzyme complex pyruvate dehydrogenase. Acetyl CoA then enters a sequence of reactions called Kreb's cycle and is broken down into CO2 and H2O. The energy released during these reactions is stored in the form of NADH and FADH2.
The NADH and FADH2 are oxidized by giving their electrons to O2 via electron transport chain. During this oxidation, the proton concentration gradient is generated across the inner mitochondrial membrane which in turn drives the process of ATP synthesis.
The transfer of antibodies from a mother to the fetus. This occurs naturally, and since it is the transfer of antibodies, it is passive immunity.
The process of cloning effectively involves taking a cell from your body and turning it back into an embryo. The embryo would then either develop into a human being as has been proposed by various scientists around the world and which is currently banned, or it would be turned into a stem cell.
Answer:
nitrogenous bases from the cytoplasm link up with an exposed complementary base