The hormone that helps plants respond to drought is a. auxin. b. abscisic acid. c. cytokinin. d. ethylene.

Video transcript

Hello, everyone here's our next question. Absent sick acid is a plant hormone that helps plants respond to. And we've got choices about different types of stress, nutrient stress, water stress, light stress and wind stress and obsessing acid is a pretty fascinating um hormone implants and it is produced in all sorts of different tissues of the plant. I can respond to all sorts of things. Um Maybe the main one is. It aids in closing the stigmata. Those are those little um openings on plant leaves um Where water can evaporate in the process of transpiration that as part of the process leading water to come up from the roots through the plant. Um But when the close to mata are closed, that reduces that water evaporation and it does this by it rapidly changes the osmotic potential of the guard cells around the Samata causing those tomato to shrink. And as you can see if it reduces the evaporation from the leaves, that helps it respond to water stress because in times of low water, if the plant is losing less water through evaporation, that helps it tolerate those situations. So we can choose choice B water stress as a correct answer through this action of closing this tomato. But good to know that that specific asset also has lots of other actions. It slows growth and causes the growth of scales over little leaf buds as a response to very cold conditions. So it helps a plant withstand cold stress. But we can see cold stress isn't one of the choices that we have. Um It also as well as closing this tomato, it can help with water stress in um that it is produced when the roots encounter very compacted soil, indicating perhaps dry soil. Um or when the roots themselves are drying up our desiccated that causes the production of cystic acid leading to this closing of this tomato. And it also helps the plant withstand high salinity, high salt in the soil um or heavy metals just by again, just generally slowing growth and inhibits fruit ripening and just kind of tells the plant to slow down. And finally it can also induce seed dormancy. So induces um induces seed dormancy. Which also is of course, another way of helping a plant endure lots of stressful situations since it prevents the plant from germinating when the conditions are poor. So another way it helps plants respond to water stress. So again, cystic acid plant hormone helping plants respond to choice be water stress. And the other answers here. Other kinds of stressors that are not ones that optimistic acid helps with a nutrient stress. See, light stress and the wind stress are not. Among those things we talked about high salinity, we talked about cold um and of course dry conditions um as things that stick acid helps with. See you in the next video