The correct answer is fixed migration pattern.
Extinction means termination of last member of a particular species. This can be due to various factors. The reason could be natural or human interventions. The best characteristics of an organism to be less likely to face extinction are the fixed migration pattern. Migration of that particular species in a fixed pattern will make them adapt different environment. This saves the species from natural extinction. Even if the species of a particular geographical area dies the migrated species will be alive to breed and save the species from extinction.
Answer: I would go with B. Here’s why: An index fossil is usually easily recognizable, and underwent a wide geographic distribution. What leads me to believe B is the correct answer, is because it’s something that existed “ all over the world”.
Answer:
The correct answers is: I would predict that animals with longer loops of Henle would be able to concentrate their urine more than animals with shorter loops, and thus they would more likely survive in desserts and other dry areas.
Explanation:
The<em> Loop of Henle</em> is a tubule system that connects the proximal convoluted tubule to the distal convoluted tubule in a nephron, the functional and structural unit of the kidney. Its primary job is to establish a concentration gradient in the kidney's medulla by creating a high urea concentration deep in the medulla using a countercurrent multiplier system that uses electrolyte pumps. Through this mechanism, <u><em>water is reabsorbed to concentrate the urine and impede dehydration</em></u>.
The length of the loops of Henle is of great importance for the countercurrent multiplier system - <u>the longer they are, the more concentrated the urine can get</u>. Therefore, animals with longer loops can survive better in habitats where there is not much water around.
