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IB Biology videos / A1.1.4 Adhesion of water to materials that are polar or charged and impacts for organisms Free video lesson IB · Biology
Biology A1.1.4 Learn Biology A1.1.4 in this free IB Biology video lesson for A1.1.4 Adhesion of water to materials that are polar or charged and impacts for organisms.
About this video Learn Biology A1.1.4 in this free IB Biology video lesson for A1.1.4 Adhesion of water to materials that are polar or charged and impacts for organisms.
The video discusses the concept of adhesion of water to polar or charged materials and its significance for organisms. It explains how water molecules stick to other substances, facilitating capillary action , which is crucial for the movement of water through plant vessels and soil.
Key points include:
Polar molecules have an unequal sharing of electrons, resulting in slight charges, while ions have complete positive or negative charges.Cations are positively charged ions formed when electrons are lost, whereas anions are negatively charged ions formed when electrons are gained.Capillary action allows water and dissolved ions to travel from plant roots to leaves, essential for plant survival.
This process is vital for maintaining moisture in plants and supporting their overall health.
Video transcript 00:00 Hello everyone, this is Hannah
00:02 from revision dojo and today
00:04 we're going to be looking
00:04 at Silvis Point A1 .1
00:06 .4. This is the adhesion
00:08 of water to materials that
00:09
are polar or charged and
00:11 the impacts for organisms. Okay,
00:13 so let's get an understanding
00:14 of what this term adhesion
00:16 means. So as water molecules
00:18 also stick to other substances,
00:21 this aids in a process
00:22 known as capillary action and
00:24 this helps water move through
00:25 plant vessels. So water can
00:28 through the pores in the
00:29 structure of the soil. So
00:31 imagine just a dry bit
00:34 initially going to be dry
00:35 and if we either water
00:38 rains, this becomes wet with
00:40 that water. And as it
00:44 to be drawn through the
00:45 roots to be transported for
00:47 the vessels. And also this
00:49 water maintains not only the
00:51 wetness of the soil, but
00:52 also the wetness of the
00:53 structures. And then when water
00:56 Another portion of water can
00:58 then be also absorbed to
00:59 what this part of the
01:00 plant that is evaporated up
01:02 through the plant. And this
01:04 keeps the moisture of the
01:05 structure providing a life medium.
01:08 Okay, so let's look at
01:09 a few of these definitions
01:10 in a bit more detail.
01:12 So we have looked at
01:13 adhesion. Now let's also look
01:18 at what polar means. Let's
01:21 is. And let's also differentiate
01:24 the cation and an anion.
01:32 Okay, so as we mentioned,
01:33 adhesion is essentially the ability
01:34 of water to stick to
01:35 other molecules so it can
01:37 be useful for transport. Now,
01:39 a polar molecule is essentially
01:41 this arises from when there
01:44 is an unequal sharing of
01:46 electrons between atoms and a
01:48 molecule. Now, a classic example
01:50 of this is our water.
01:52 molecules are polar molecules. We
01:54 also have glucose molecules. This
01:56 is another classic example of
01:58 a polar molecule, whether it's
02:00 an unequal sharing of electrons
02:01 between atoms and the molecule.
02:05 Okay, now these polar molecules,
02:08 they result in a slightly
02:09 negative or a slightly positive
02:11 charge. We define that as
02:13 delta negative or delta positive.
02:17 Now let's look at what
02:20 essentially when electrons either leave
02:25 atom. Now, with an ion,
02:28 we're not going to have
02:28 this partially negative or partially
02:30 positive charge. We're going to
02:31 have a completely negative or
02:33 a completely positive charge, which
02:35 brings us onto our next
02:36 point, which is cations and
02:38 anions. Now, these are pretty
02:40 much interconnected. Both of these
02:43 with the ions, because a
02:44 cation is a positively charged
02:48 is a negatively charged aisle.
02:50 So what happens with a
02:51 counteron is electrons leave the
02:53 atom. So we have loss
02:56 of electrons resulting in an
02:57 overall positive charge. And then
02:59 with an anion, we have
03:01 electrons going to that atom.
03:04 So we have an overall
03:06 negative charge. OK. Now, let's
03:12 look at the impact of
03:14 adhesion for organisms.
03:16 So as I was mentioning
03:18 before, there is a process
03:20 known as capillary action. So
03:23 let's look at this process
03:24 in a bit more detail.
03:31 Capillary action. So capillary action
03:39 is essentially the movement of
03:41 water through a narrow space
03:44 often in opposition to external
03:46 forces like gravity. So I
03:49 want you guys to think
03:50 about the trees and the
03:52 plants that you see outside
03:53 on a daily basis. Now
03:55 these trees and plants they
03:56 could not thrive without capillary
03:58 action. Because capillary action is
04:00 what helps bring water into
04:02 the roots with the help
04:03 of adhesion and cohesion. Water
04:06 and dissolved ions, they can
04:07 move all the way down
04:09 from the roots all the
04:10 way up to the leaves
04:12 branches. And you can imagine
04:15 that this is essential for
04:17 water to travel to the
04:19 organisms, especially our plants and
04:20 trees, because without this water,
04:22 they will not be able