<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:
High amounts of fluoride
Explanation:
Teeth cleaning agents can contaminate one's blood with fluoride, something that it is only healthy to accumulate a small amount of.
the phospholipids are tightly packed togther and the membrane has a hydrophobic interior.
Answer:
Bad mutation: deletion/addition mutation
Good mutation: silent mutation
Explanation:
Addition or deletion mutation results in the reading frame of codons to be changed, leading to a extensive missense mutation that will lead to a non-functional protein product to form.
Good mutation are silent mutations that leads to no change to the final product but causes codons to change in sequence. This increases genetic diversity in the gene pool that enables the species to be more resilient to environmental changes.
