The correct option is C.
Scientists believed that the earth tectonic plates are in constant motion, this motion is slow and its rates vary. The motions of the tectonic plates are caused by the convection current which is found in semi molten mantle. The convection current are created by heat within the earth surface. When a semi molten rock is heated, it become less in density compared to its surrounding and thus rises up. When the less dense molten rock reaches the crust above, it spread out and carries the tectonic plate above with it. When the molten magma cools down, it sinks and the whole process is repeated leading to continuous movement of the tectonic plates.
In British Columbia, western Canada, renowned for its's coniferous forests, the poaching of protected magnificent old growth trees is fairly common and examples have been found in our park-protected areas of cutting of 800-1000 year old giants in the Carmanah Walbran Provincial Park.
Answer:
Drawing your town helps promote brain power. Hope this helps stay safe ❤!
Answer:
Hydrogen peroxide is toxic.
Explanation:
Hydrogen peroxide is a natural product of the reactions in the cell. However, it is toxic to cells and has to be broken down.
Catalase catalyses the breakdown of hydrogen peroxide into water and oxygen. It is found in all living cells and is very important to prevent the build up of hydrogen peroxide. If catalase didn't work quickly, hydrogen peroxide would accumulate in the cell and poison it, causing the cell to die.
Answer:
The correct answer is ''loss of acetylcholine receptors in the end-plate membrane.''
Explanation:
Myasthenia gravis represents a human autoimmune disease. The neuromuscular junction abnormalities that occur in this disease are due to antibody-mediated processes. A reduction in the number of functional acetylcholine receptors on the postsynaptic membrane was established to contribute to the physiological abnormalities of myasthenia gravis. The reduction in receptors is due to immunological alterations directed against the acetylcholine receptor. Normally, when acetylcholine binds to its receptor, it opens allowing the rapid entry of cations, especially sodium. With this, the depolarization of the postsynaptic region of the muscle fiber occurs. Although acetylcholine is normally released in myasthenia gravis, it is not capable of causing an action potential in the muscle sufficient to initiate or weaken contraction. In patients with myasthenia gravis, failure to activate muscles is responsible for myasthenic fatigue. Most patients have elevated serum titers of antireceptor antibodies, which in turn accelerate receptor degradation.
