Answer/Explanation:
EGFR stands for epidermal growth factor receptor. It is a transmembrane protein acting as a tyrosine kinase receptor for epidermal growth factor ligands, which are associated with promoting cell division and proliferation. When epidermal growth factor binds to the receptor, it becomes activated and undergoes dimerization and autophosphorylation.
A mutation could occur making the receptor overactive. That is, it does not require ligand binding to become activated, meaning it is always in an "on" state. This would lead to uncontrolled proliferation, a hallmark of cancer.
Earth's atmosphere helps maintain a constant temperature.
Heat from the sun makes it through near the Antarctic (where the hole is) is melting the ice and not allowing some key species to feed. seals don't have ice to come up for air through like normal so polar bears starve. loss of land means less food for a lot of species because the hunting grounds is closing and there is no room to expand.
Limestone deposits can help researchers learn about what the area was like thousands of years ago as Limestone can contain fossilized plants and animals.
Explanation:
- Limestone often contains fossils of shelled sea creatures. Entire reef formations and communities of organisms are found preserved in limestone.
- The types of fossils found in limestone include coral, algae, clams, brachiopods, bryozoa and crinoids.
- Limestone is a sedimentary rock made almost entirely of fossils.
- Fossils are the remains of ancient plants and animals, like an imprint in a rock or actual bones and shells that have turned into rock. Fossils are found in sedimentary rocks and hold the clues to life on Earth long ago.
- Limestone is composed of the mineral calcite; calcium carbonate. It often has variable amounts of silica in it, as well as varying amounts of clay, silt, and sand. Limestone rocks fall under the category of sedimentary rocks that are made from mineral calcite.
