Topic content:
The scientific research value of Chinese alligator lies in
A. It is a huge reptile
B. The body has many characteristics of ancient reptiles, known as the "living fossil" of Mesozoic animals
C. Crocodile leather has great economic value
D. Alligator sinensis has precious medicinal value
Best answer:
B
Answer analysis:
There is no explanation for this question
Test core:
Threats to biodiversity and their causes: The threats to biodiversity are the result of the combined effects of various factors. The rapid growth of population and the increasing demand for resources from the natural environment are the fundamental reasons for the threat to biodiversity. The reasons for the threats to biodiversity mainly include the following four aspects: (1) The destruction or loss of habitat is the main reason for the threats to biodiversity.
(2) Predatory development and utilization: indiscriminate cutting, hunting and killing.
(3) Environmental pollution.
(4) Alien invasion. The extinction of species is a natural process, but the current human activities have greatly accelerated the speed of species extinction. Once a species is extinct, it will not be renewable. The loss of biodiversity will cause a fundamental crisis in agriculture, medicine, health care and industry, and damage the ecological environment, threatening the survival of human beings.