<span>ny scientist studying a species could change the name. These long ... To classify organisms, scientists use similarities and differences among species. ... MATERIALS ... also use genetic evidence, which is found within an organism's DNA.</span>
Answer: The immune system
Explanation:
The immune system is a complex network of proteins and cells that defends the body against infection or any invasion. The human defense system in the body is actually made up of entire organs and vessel systems like the lymph vessels. The immune system is made up of organs that control the production and maturation of certain defense cells.
Initially, all living things are subjected to attack from disease causing agents. Even bacteria, so small that more than a million could fit on the head of a pin, have systems to defend against infection by viruses. This kind of protection gets more sophisticated as organisms become more complex.
So abiotic means nonliving, so the only abiotic option is B. the gravel on the bottom of the aquarium.
The correct option is 3). 0.5. Since recessive homozygous are 25% of the total individuals, we could assume that their parents genotype was heterozygous. Only a double heterozygous cross (that is Aa -male- <> Aa -female) could produce the observed (25%) homozygous proportion. Following this assumption, the heterozygous proportion will be 50%.
