<span>The thymus.The thymus plays an important role in the development of T-lymphocytes which is an important type of white blood cell. It reaches maximum development at puberty and then the thymus begins to get atrophied (the shrinking of the thymus with age) and then the thymic stroma is replaced by fat tissue. Loss of thymic function is thought to contribute to weaker immune system of the elderly, increasing instances of diseases such as cancers and other infections.</span>
A high level of gene flow into a population increases genetic diversity in a population. A high level of gene flow out of a population decreases genetic diversity in a population. Genetic drift is the change in allele frequencies due to "sampling error" factors. Typically, genetic drift has the biggest impact on small populations.
Gene flow (or gene migration) is a mechanism of evolution (change the allele frequencies) which transfers genetic variation among populations due to migration. High level of gene flow decreases the genetic differentiation between the two populations.
Genetic drift is a mechanism of evolution that acts by chance (“sampling error”) often when a population is reduced in size by a natural disaster (bottleneck effect) or when a small group leaves the main population and forms a colony (founder effect).
Answer:
The most likely preferable option will be - A.
A. Insects.
Explanation:
The basic features of insects -
- Insects have an exoskeleton outside of their body or a shell-like covering on the outside of its body.
- Insects have a body with three segments: head, thorax, and abdomen.
- Insects have two large eyes and a pair of antennae on top of their heads.
- Insects have six legs (3 pairs).
- Insects have two pairs of wings on the dorsal part of their body.
<span>Of SiF4 and SiBr4, the atom SiF4 is more polar. This is because the cation of both molecules are Silicon, but the anions of each are different. In SiF4, the anion is Fluorine, which is more electronegative than the Bromine in SiBr4, which creates a larger dipole, which results in a more polar molecule.</span>
No 6 is common for N and H. 3 is only for H(Hydrogen).
For finding the number of hydrogen atoms we should multiply 6 with 3
So, 6*3 = 18. So there will be 18 hydrogen atoms in 6NH₃
