Here's what happens: 1  The receptors, which are nerve endings in your nasal passageways, detect an irritant. 2  Nerves carry these impulses to the sneezing center in your brain stem. 3  The sneezing center sends its instructions along your facial nerve and the nerves that lead to your lungs and diaphragm. 4  Your eyes start to water, and your nasal ...
TOP. THE MAIN EVENTS OF PHOTOSYNTHESIS (higher level). Photosynthesis takes place in two stages; the light stage and the dark stage. The light stage needs light so it is called the light-dependent stage. The dark stage is called the light-independent stage. TOP. THE LIGHT STAGE. The light stage takes place in the chloroplast s thylakoid membranes. The events of the light stage are as follows: 1. Light Absorption: All the colours of white light (except green light) are absorbed by pigments in the chloroplast.
The first stage of photosynthesis is a series of reactions, known as the light reactions, that takes its name from the fact that light is required. The products of the light reactions are ATP, NADPH, and oxygen. ATP and NADPH are special, energy-storing molecules. The energy stored in these molecules is later used to make glucose, which is the molecule plants use for long-term energy storage. Lets take a closer look at the light reactions.