The answer is A; all of the above
Mammalian fertilization comprises sperm migration through the female reproductive tract, biochemical and morphological changes to sperm, and sperm-egg interaction in the oviduct. Recent gene knockout approaches in mice have revealed that many factors previously considered important for fertilization are largely dispensable, or if they are essential, they have an unexpected function. These results indicate that what has been observed in in vitro fertilization (IVF) differs significantly from what occurs during “physiological” fertilization. This Review focuses on the advantages of studying fertilization using gene-manipulated animals and highlights an emerging molecular mechanism of mammalian fertilization.
According to the research, the linear vein is a tributary blood vessel of the hepatic portal vein.
<h3>What is the hepatic portal vein?</h3>
It is a blood vessel that carries deoxygenated blood from the digestive organs and the spleen to the liver.
The linear vein is one of the branches of the celiac trunk that supplies the spleen and gives off branches to the stomach and pancreas.
Therefore, we can conclude that according to the research, the linear vein is a tributary blood vessel of the hepatic portal vein.
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A genetic outcome of a genetic cross between the same parents is independent of previous outcomes.
<h3>What is genetic variation?</h3>
Genetic variation can be defined as the genetic poll of an organism, which is the raw material trough which evolution can occur by natural selection.
During sexual reproduction, the formation of gametes generates different genetic backgrounds which are independent of distinct gametes.
In conclusion, each genetic outcome of a genetic cross between the same parents is independent of all previous outcomes.
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Mechanical is. the digestion that occurs
