Answer:
2%
Explanation:
The scientist believe that around 2% of the species that existed on Earth have been preserved in the fossil records. It is still a hot debate about it though, as there are only around 250,000 species identified in the fossil records so far, which is less than a quarter from the species that live in the present.
The reason why scientists believe that the majority of the species have not been preserved are very logical though. One of the reasons is that lot of species existed very long time ago, so their remains just didn't lasted so long. Other reason is the movement of the plates, where we have situation where plates that existed in the past have been totally suducted and melted in the mantle, while others are at the verge of it, so every fossil with them is melted and destroyed too. Another reason is that lot of species do not have hard parts, solid bone structure, so their preservation has been pretty much impossible,
Answer:
A proton and an electron have an equal amount but an opposite type of charge. Thus, if an atom contains equal numbers of protons and electrons, the atom is described as being electrically neutral.
Explanation:
The five-kingdom<span> system of classification for </span>living<span> organisms, including the </span>prokaryotic<span> Monera and the </span>eukaryotic<span> Protista, Fungi, Plantae and Animalia is complicated by the discovery of archaebacteria. I hope this is related to the question</span>
Answer: <span>D </span>Mucosa—absorbed by villi; submucosa—enters blood vessels
To absorb the nutrient, the digestive tract will need an enzyme to break down the food. The food will be absorbed by villi, which located in the mucosa layer. After absorbed, the nutrient will be moved into submucosa where the blood vessels are abundant. The nutrient will be sent to the body using blood vessel network.
the stomach is located inferior to the diaphragm and lateral to the liver on the left side of the abdominal cavity. The stomach forms part of the gastrointestinal tract between the esophagus and the duodenum