In humans gene flow usually comes about through the actual migration of human populations, either voluntary or forced. Although gene flow does not change allele frequencies for a species as a whole, it can alter allele frequencies in local populations.
Hopefully this helps.
Do you mean sediments???
the type of rock formed from sediments is called sedimentary rocks
Answer:
Saliva lubricates and moistens these food particles
Explanation:
As teeth help to break down large pieces of food into lots of smaller pieces, saliva is released and mixes with the smaller food pieces. Saliva lubricates and moistens these food particles such that a ball-like mixture of food and saliva that is known as a bolus is formed, which can then be easily swallowed.
I would believe the correct responses would be option 1,2,4.
