Answer:
The mechanism by which cells regulate their ability to respond to extracellular messengers is known as receptor signalling.
Explanation:
Cells senses an environment and communicate which each other through ligand-induced activation of signalling receptors at the cell surface. Signalling receptors enter the endocytic pathway and are sorts into various compartments. Endocytosis regulates cell signalling by controlling the number of receptors available for activation in plasma membrane and activation of receptors or downstream effectors often stimulate receptor endocytosis.
Answer:The effect of gene flow is to reduce genetic differences between populations, thereby preventing or delaying the evolution of the populations in different geographical areas into separate species of the pathogen.
Explanation:
It is the serous membrane
The visibility is the given distance, condition and atomsphere
Answer:
They found evidence of an impact crater in Mexico
Explanation:
The K-Pg boundary is the boundary between the Cretaceous period and the Paleogene period, but also marking the end of the Mesozoic era and the beginning of the Cenozoic era. This boundary is dated to roughly 66 million years ago. The K-Pg boundary is characterized with a mass extinction. The dominant organisms on Earth all died out, including the dinosaurs, both terrestrial and aquatic, as well as the flying reptilians, with only the birds surviving from that super-family. The reason for the mass extinction has been an impact with an asteroid or a comet, that was very large and hit the Earth where the Yucatan Peninsula in modern day Mexico is located. The impact was devastating, with heat waves, tsunamis, earthquakes, triggering of the majority of the volcanoes, wildfires, all combined managed to devastate the environment, thus big portion of the species living in it as well. The lucky survivors were smaller organisms, and the mammals turned out to be the most successful in occupying the empty niches and have became the dominant organisms on the planet.