Answer: <em>D. Causes an accumulation of lipids in brain cells</em>
Explanation:
Tay-Sachs disease is caused by a genetic mutation in the <em>HEXA</em> gene. It is an autosomal recessive disease that causes the mutation on an enzyme, which metabolizes <em>GM2 Ganglioside</em> in nerve cells, this leads to a build-up of the molecule in brain cells. At the moment there is no cure for the disease, only support treatment is available.
Answer: German scientist Alfred Wegener
Explanation: <em>In the early 1900s, the German scientist Alfred Wegener noticed that the coastlines of Africa and South America looked like they might fit together. He also discovered evidence that the same plant and animal fossils were found along the coasts of these continents, although they were now separated by vast oceans.</em>
The correct answer is option A, that is, development often causes habitat fragmentation, which can threaten biodiversity.
Fragmentation is usually illustrated as a reduction in some of all the kinds of natural habitats in a landscape, and the differentiation of a landscape into smaller and more isolated segments. With the development of the fragmentation process, the ecological influences will modify.
Fragmentation can be a result of natural procedures like floods, fires, and volcanic activity, but it is more generally caused due to human activities like an increase in the number of roads, housing developments, shopping centers, and parking lots.
With the enhancement in human activities, the effect of fragmentation become more. Eventually, it results in the devastating influences on the local species, a complete modification to the landscape, and the loss of the region's wilderness heritage.