The genetics of red hair appear to be associated with the melanocortin-1 receptor (MC1R), which is found on chromosome 16. Eighty percent of redheads have an MC1R gene variant.
I cannot find this source for this I'm sorry. I meant to add it but I lost the site
Answer:
A. Type of soil
Explanation:
A control experiment is the one that is used to checkmate the real experiment.
In this case, the fourth jar that contains the mixture of all the types of the soil is considered as the control experiment.
In a nutshell, it should be generally understood here that the type of soil serves as the control for the experiment.
Answer:
The answer is:
B. Worms consuming the blood from mammals.
Algae isn't causing any harm to the sloth, rather its providing it with camouflage to hide from predators. Both creatures benefits since the algae gets to eat any parasites and other things in the sloths fur, plus they get a free ride and home in the process. The sloth isn't harmed and is helped by the algae since it provides camouflage (mutualism).
Tree frogs aren't causing harm to the trees since they are only using them to hide from predators, the tree serves as protection for the frogs and aren't harmed in the process (commensalism).
Two fish protecting each other from predators aren't harming each other in any way, rather they are protecting each other from another animal that wants to eat them (mutualism).
The worms however are harming the mammals because they are consuming the mammals blood, this is parasitism since one animal is benefiting and the other is harmed.
Hope this helps! :)
