<h2>Neural crest </h2>
Explanation:
The neural crest likely forms: neurons and glia of the peripheral nervous system
- The neural crest are bilaterally paired strips of cells arising in the ectoderm at the margins of the neural tube
- In the body region, neural crest cells also contribute the peripheral nervous system (both neurons and glia) consisting of sensory ganglia (dorsal root ganglia), sympathetic and parasympathetic ganglia and neural plexuses within specific tissues/organs
- The nervous system is made up of specialized cells which includes nerve cells (or neurons) and glial cells (or glia)
- Neurons are the basic functional units of the nervous system, and they generate electrical signals called action potentials, which allow them to quickly transmit information over long distances
- Glia are also essential to nervous system function, but they work mostly by supporting the neurons
Answer: A: Its fertile oases enabled farmers to grow enough food for themselves and for sale.
Explanation: The Arabia region is a region located within the Arabian desert. A desert is an area of extreme heat, often dry weather condition with barren lands that cannot support agriculture and food production. An oases on the other hand is a region of luscious, cultivate-able land within a desert.
Food is one of the most important basic needs of man and hardly can anyone survive without food for more than twenty days. Hence, the presence of oases within the otherwise dry environment of the Arabia region is a major protection against death from hunger.
Taking a closer look at other options, none of them guarantees food supply and income to the Arabia region unlike food production in oases. Hence, the fertile oases is really the most important factor that serves as protection in the region's history.
Correct option: A
That is false. Non-renewable energy sources are the major sources of energy production.
Complete question:
In a separate study, 68 rock pocket mice were collected from four different, widely separated areas of dark lava rock. One collecting site was in Sonora, Mexico. The other three were in Chihuahua, Mexico. Dr. Nachman and colleagues observed no significant differences in the color of the rocks in the four locations sampled. However, the dark-colored mice from the three Chihuahua locations were slightly darker than the dark-colored mice from the Sonora population. The entire Mc1r gene was sequenced in all 68 of the mice collected. The mutations responsible for the dark fur color in the Sonora mice were absent from the three different populations of Chihuahua mice. No Mc1r mutations were associated with dark fur color in the Chihuahua populations. These findings suggest that adaptive dark coloration has occurred at least twice in the rock pocket mouse and that these similar phenotypic changes have different genetic bases.
How does this study support the concept that natural selection is not random?
Answer:
The study supports the concept that natural selection is not random because in different areas with the same or very similar environmental characteristics, the same phenotype was produced by different types of mutations.
Explanation:
All of the sampled animals are inhabiting dark substrate. Probably animals needed to camouflage to survive. Natural selection must have driven them to produce dark color, similar to the substrate color. So animals from the different regions suffered different mutations that drove them to have almost the same dark fur color. The environmental condition is favoring the same phenotype.
True. Monocots veins run parallel
