Answer:
D) The hydrogen and oxygen atoms of water are split in the light reactions, and oxygen is released. In the Calvin cycle, hydrogen atoms join with the carbon and oxygen atoms of carbon dioxide to form carbohydrates.
Explanation:
Photosynthesis is the process by which plants produce carbohydrates (sugars) from carbon dioxide in the atmosphere and water using the energy of sunlight. The process of photosynthesis occurs in two stages: (i) the light-dependent stage and (ii) the light-independent stage.
Light reactions: In this stage, the hydrogen and oxygen atoms of water are split in the light reactions, and oxygen is released. Also, the energy storage molecule ATP and the reduced electron carrier NADPH are produced.
Light-independent reaction or Calvin cycle: in this stage, carbon atoms from CO₂ are incorporated into ribulose-5-phosphate and used to produce glyceraldehyde-3-phosphate, a three-carbon sugar using the energy of ATP and NADPH from the light reactions. Essentially, hydrogen atoms join with the carbon and oxygen atoms of carbon dioxide to form carbohydrates.
Multiple sclerosis develops when nerve cells in the brain and spinal cord lose the insulating mylien sheaths that surround them.This can happen anywhere in the CNS and is random.
Symptoms are Muscle weakness, loss of sensory input from the skin and other areas, poor vision and mental problems due to the loss of the protective mylien the neurons stop conducting the impulses and hence there is a loss of functions controlled by the areas of the CNS concerned.
Hope this helps! :)
Upwelling waters occur when the warm water, on the surface of the oceans in the equatorial regions are pushed towards the poles by winds and the denser cold currents on the ocean bottom move up to replace the displaced waters. The denser currents are usually nutrient-filled and are an ideal substrate for growth of phytoplankton as they warm up on the surface. The algae bloom attracts fish and other producers in the sea. The producers consequently attract other carnivorous fish.
Answer:
Option B
Explanation:
The formal study of fossils, its collection and documentation started in 1700s during the period known as “Age of Enlightenment” It was during this time period that scientist noticed rock fossils and started making fossil collection. During the 1800s, areas with rocks fossils were studied and compared.
Further, Charles Lyell and Charles Darwin showed strong connection between biological evolution and geological evolution of planet earth. Hence, the earlier traces of fossils i.e before a certain period could not be studies due to late pioneering of fossil based evolutionary science. It is also due to limitations with radioactive dating
Hence, option B is correct
