<span>A gamete needs only half the number of chromosomes because two gametes join together hope his helps you
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A common way that humans pollute water is through the addition of nutrients (fertilizers and sewage) to water as nonpoint source pollution. These added materials are full of nitrogen and phosphorus, two nutrients that encourage the growth of aquatic producers, such as algae.
<span>Simple.
All of the millions of different life forms (the diversity of life) have come about by natural selection, whereby random mutations in the genes have either succeeded or failed.
But all life can be traced back to a common single-celled origin. Thus we have the unity of life where we (possibly) share more than 50 % of our DNA with a crocodile.eg:analogous organs, homologous organs.</span>
All isotopes of hydrogen will always contain one proton, as a change in the amount of protons will change the substance. Assuming all isotopes aren’t ions and therefore don’t have a charge, then each of these isotopes has one electron. The only difference between them is the amount of neutrons to account for the different atomic masses.
H1
one proton
one electron
zero neutrons
H2
one proton
one electron
one neutron
H3
one proton
one electron
two neutron