<span>Only one sperm normally fuses
with an egg because if more than one sperm fuses, through a process
called polyspermy, development of the zygote usually stops.
</span>
<span>Fertilization of one egg by
two sperm is possible, but the resulting zygote is almost never viable
because such a zygote would have three sets of chromosomes instead of
the normal two. This condition, called triploidy, is usually
incompatible with life. Those rare triploid infants that do survive to
term have severe and multiple birth defects and rarely live more than a
few days. </span>
Answer: After seven months.
Explanation:
The blood carries various substances that must be transported from one part of the body to another. Red blood cells are an important component of the blood because their function is to carry oxygen to the body tissues and exchange it for carbon dioxide, which is carried and removed by the lungs.
Erythropoiesis is the process of red blood cell (erythrocyte) production. It is stimulated by a decrease in O2 in the circulation, detected by the kidneys, which then secretes the hormone erythropoietin. This hormone stimulates the proliferation and differentiation of red blood cell precursors, which triggers an increase in erythropoiesis in hematopoietic tissues and ultimately in the production of red blood cells. <u>In adults, red blood cells are formed in the red bone marrow.</u>
In early developing fetuses, erythropoiesis occurs in the mesodermal cells of the yolk sac. In the third or fourth month, erythropoiesis moves to the liver. After seven months, erythropoiesis occurs in the bone marrow.
He would say that Lamarck's theory is wrong. Lamarck's theory stated that traits that are used are passed on to the offspring. In other words, if an organism changes during its lifetime in order to adapt to its environment, then its changes will be passed on to its offspring. This is wrong because this means that organisms pass on traits based on genetic information and not based on the environment of the offspring.
Hope this helps.