Answer:
a neutral marker
Explanation:
A gene polymorphism can be defined as the existence of two or more variants of the same gene (i.e., alleles). A polymorphism may be a difference of one nucleotide base in DNA (single nucleotide polymorphisms, SNPs) or indels (i.e., insertions and deletions). A gene under selection will have many polymorphisms in its sequence which may lead to convergence and disproportionate divergence among sequences, and thereby will be uninformative to trace the evolutionary history among individuals within a species, population, etc. Conversely, neutral molecular markers exhibit fewer nucleotide differences, it is for that reason that they are commonly used to determine genetic population structure among individuals.
The answer: Ventricles.
There are four ventricles in the brain all connected between them,
where the cerebrospinal fluid is produced. There is a choroid plexus in each ventricle that produce the fluid.
The four ventricles:
<span><span>- 2 lateral ventricles right and left (one for each hemisphere)</span>
-third ventricle<span>
- fourth ventricle</span></span>
Leaf transpiration occurs through stomata, and can be thought of as a necessary "cost" associated with the opening of stomata to allow the diffusion of carbon dioxide gas from the air for photosynthesis. Transpiration also cools plants and enables mass flow of mineral nutrients and water from roots to shoots
