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plants and water

why do water and mineral ions get absorbed by root hair cells by diffusion, osmosis *and* active transport? as in what is the difference that there has to be different ways of getting water?
(i know what each three terms mean btw)
Original post by ArizonaRobbins
why do water and mineral ions get absorbed by root hair cells by diffusion, osmosis *and* active transport? as in what is the difference that there has to be different ways of getting water?
(i know what each three terms mean btw)

It just depends on the environment the plant is in. If the soil is very nutrient-dense there will be more mineral ions in the soil than in the plant so the ions will be able to just diffuse in but plants need a lot of minerals so usually need to transport more ions in than what would just diffuse in against the concentration gradient, therefore, needing active transport. Water always moves in by osmosis (and the active transport of mineral ions into the plant decreases the water potential in the plant so more water will diffuse in by osmosis).
Reply 2
dunno how mineral ions get into a plant via diffusion as they are charged there is no way for them to get through the phospholipid bilayer. Ions must be moved by facilitated diffusion or by active transport. They are normally transported via facilitated diffusion by channel proteins as it is passive so requires no energy but this is only carried out down the concentration gradient. So active transport using carrier proteins can be used to transport ions when they are large or if a concentration gradient is wanting to be made e.g. in phloem loading.

Water diffuses via 3 ways: apoplast, symplast and vacuolar.

apoplast: water moves through call walls of cells until it reaches they Xylem. The majority of water moves using this path as it has the least amount of resistance

symplast: water enters cytoplasm through the plasmodesmata via osmosis. As the root hair cell has higher water potential than the next cell across water moves through cells down the concentration gradient

vacuolar: water moves through the vacuoles of cells. This process is very slow but allows individual cells to absorb water
Reply 3
Original post by Cyion
dunno how mineral ions get into a plant via diffusion as they are charged there is no way for them to get through the phospholipid bilayer. Ions must be moved by facilitated diffusion or by active transport. They are normally transported via facilitated diffusion by channel proteins as it is passive so requires no energy but this is only carried out down the concentration gradient. So active transport using carrier proteins can be used to transport ions when they are large or if a concentration gradient is wanting to be made e.g. in phloem loading.

Water diffuses via 3 ways: apoplast, symplast and vacuolar.

apoplast: water moves through call walls of cells until it reaches they Xylem. The majority of water moves using this path as it has the least amount of resistance

symplast: water enters cytoplasm through the plasmodesmata via osmosis. As the root hair cell has higher water potential than the next cell across water moves through cells down the concentration gradient

vacuolar: water moves through the vacuoles of cells. This process is very slow but allows individual cells to absorb water

i think hes still at gcse level bud
Original post by learningizk00l
It just depends on the environment the plant is in. If the soil is very nutrient-dense there will be more mineral ions in the soil than in the plant so the ions will be able to just diffuse in but plants need a lot of minerals so usually need to transport more ions in than what would just diffuse in against the concentration gradient, therefore, needing active transport. Water always moves in by osmosis (and the active transport of mineral ions into the plant decreases the water potential in the plant so more water will diffuse in by osmosis).

ohh right that makes a lot more sense, thanks!
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Original post by Cyion
dunno how mineral ions get into a plant via diffusion as they are charged there is no way for them to get through the phospholipid bilayer. Ions must be moved by facilitated diffusion or by active transport. They are normally transported via facilitated diffusion by channel proteins as it is passive so requires no energy but this is only carried out down the concentration gradient. So active transport using carrier proteins can be used to transport ions when they are large or if a concentration gradient is wanting to be made e.g. in phloem loading.

Water diffuses via 3 ways: apoplast, symplast and vacuolar.

apoplast: water moves through call walls of cells until it reaches they Xylem. The majority of water moves using this path as it has the least amount of resistance

symplast: water enters cytoplasm through the plasmodesmata via osmosis. As the root hair cell has higher water potential than the next cell across water moves through cells down the concentration gradient

vacuolar: water moves through the vacuoles of cells. This process is very slow but allows individual cells to absorb water

thank you :smile:
Original post by MoJam
i think hes still at gcse level bud

i'm a she but yeah haha

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