The correct answer is - A) arthropods evolved before vertebrates did.
The arthropods have evolved much earlier than the vertebrates. They were on the scene millions of years before the earliest marine forms of the vertebrates. Because the arthropods were on the scene much earlier, they managed to use the newly formed suitable environment on the land. They were initially marine, but with only slight adaptations they were able to adapt to the terrestrial life.
Once the arthropods got out of the marine environment and started to take up the niches in the terrestrial environment, they experienced a real explosion in their evolution and diversification. They were the dominant land dwellers, and because of the lack of competition, as well as the higher levels of oxygen, they managed to reach pretty big sizes for their standards. Unfortunately for them, their brain capacity is limited to a very low level, so once the competition came on the scene, they were quickly pushed from the throne as the dominant terrestrial creatures.
Photosythesis
CO2 + H2O + ( sunlight ) = glucose + O2
The primary role of hydrochloric acid is to sterilize the food you eat and to prevent harmful bacteria from entering the GI tract. HCL also triggers the release of enzymes such as pepsin which are essential for the digestion of protein.
On the islands of the Galapagos lives a group of birds called finches. There are 13 species in this group. These species have diverse ecologies--some eat seeds, some eat insects, some eat fruit, and some even eat cactus. Although the bodies of these species look fairly similar, their beaks are very different. That is because it is their beak that is adapted to these diverse ways of feeding (Figure 8.14).
As the sun heats the surface of the oceans, two layers of water result. These layers are separated by the Thermocline.
so your answer is thermocline.
