Types of Solutions

Summary

This educational video explains the movement of materials across cell membranes due to concentration differences. It introduces three types of solutions: isotonic, where solute concentrations inside and outside the cell are equal, leading to stable cell size; hypertonic, where higher solute concentration outside causes water to leave the cell, resulting in cell shrinkage; and hypotonic, where lower solute concentration outside leads to water influx and cell swelling or bursting. The video also differentiates the effects on animal and plant cells, emphasizing the ideal conditions for each.

Takeaways

• 🌟 Materials move across membranes due to concentration differences, which drive the diffusion of solutes and osmosis of water.
• 🍹 A solution is created when a solute dissolves in a solvent, with water being the most common solvent.
• 🔄 Isotonic solutions have equal solute concentration inside and outside the cell, maintaining cell size as water moves in and out equally.
• 💧 Hypertonic solutions have a higher solute concentration outside the cell, causing water to leave the cell and potentially leading to cell shrinkage.
• 🌊 Hypotonic solutions have a lower solute concentration outside the cell, drawing water into the cell and possibly causing it to swell or burst.
• 🌿 In hypotonic conditions, plant cells absorb water and become turgid, which is beneficial for growth and reaching sunlight.
• 🐟 Animal cells in isotonic solutions experience normal water movement, maintaining cell integrity.
• 🌵 Plant cells in isotonic solutions may become flaccid, which is not ideal as it can lead to wilting.
• 🌡 Plant cells in hypertonic solutions undergo plasmolysis, where they lose water and shrivel.
• 🔬 The video script illustrates the process of lysing in animal cells, where cells burst due to the influx of water in a hypotonic solution.

Q & A

What causes materials to move across membranes in cells?

Materials move across membranes because of concentration differences, driven by concentration gradients.

What is diffusion and osmosis?

Diffusion is the movement of solute across a membrane, while osmosis is the movement of water across a membrane.

What is a solution and how is it formed?

A solution is formed when a solute dissolves in a solvent. For example, in Kool-Aid, the powder is the solute and the water is the solvent.

What does isotonic mean in terms of cell environments?

An isotonic solution has an equal concentration of solute inside and outside the cell, meaning water enters and exits the cell at the same rate, keeping the cell size constant.

What happens to a cell in a hypertonic solution?

In a hypertonic solution, there is a higher concentration of solute outside the cell. Water exits the cell to dilute the external solution, causing the cell to shrivel.

What happens to a cell in a hypotonic solution?

In a hypotonic solution, there is more solute inside the cell than outside, so water rushes into the cell, causing it to swell and potentially burst.

How do animal cells behave in isotonic, hypertonic, and hypotonic solutions?

In an isotonic solution, animal cells maintain normal water movement. In a hypertonic solution, they shrink, and in a hypotonic solution, they swell and may burst (lyse).

What is the difference between the response of plant cells and animal cells in a hypotonic solution?

In a hypotonic solution, plant cells become turgid and do not burst due to their cell walls. In contrast, animal cells can burst when too much water enters.

What is plasmolysis in plant cells?

Plasmolysis occurs when plant cells are in a hypertonic solution, causing water to leave the cell, and the cell membrane shrivels away from the cell wall.

Why do plant cells wilt when placed in an isotonic solution?

In an isotonic solution, plant cells lose their turgor pressure and become flaccid, leading to wilting because they cannot retain as much water as they need.

Outlines

00:00

🌡️ Types of Solutions and Their Effects on Cells

This paragraph introduces the concept of solutions and their impact on cells due to concentration differences. It defines a solution as a solute dissolved in a solvent, with water being the most common solvent. The paragraph discusses three types of solutions: isotonic, hypertonic, and hypotonic. An isotonic solution has equal solute concentration inside and outside the cell, leading to no net movement of water and thus maintaining cell size. A hypertonic solution, having a higher solute concentration outside the cell, causes water to leave the cell, leading to cell shrinkage. Conversely, a hypotonic solution, with less solute outside the cell, results in water rushing into the cell, causing it to swell or potentially burst. The paragraph also differentiates the effects on animal and plant cells, noting that while animal cells can burst in hypotonic solutions, plant cells' cell walls prevent bursting due to increased turgor pressure.

05:01

🌟 Osmosis and Cell Response to Hypotonic Solutions

This paragraph delves into the process of osmosis and its effects on cells, particularly in hypotonic solutions. It describes the phenomenon of lysing, where cells explode due to excessive water intake. The paragraph includes a visual aid of a blood cell undergoing lysis, illustrating the cellular explosion under a microscope. It also corrects a typographical error, noting that 'distilled water' was misspelled. The focus is on the dramatic changes cells undergo when placed in solutions with varying solute concentrations, emphasizing the importance of understanding osmotic pressure and its biological implications.

Keywords

💡Concentration Gradient

A concentration gradient refers to the difference in the concentration of a solute across a boundary, such as a cell membrane. In the context of the video, it's the driving force behind the movement of solutes and water across membranes. The video explains that materials move across membranes due to these concentration differences, with solutes moving from areas of higher concentration to lower concentration, and water moving in the opposite direction to balance the solute concentration.

💡Diffusion

Diffusion is the process by which solutes move from an area of higher concentration to an area of lower concentration. In the video, diffusion is mentioned as the movement of solute particles across a membrane, which is driven by the concentration gradient. The video uses the example of a hypertonic solution where the higher concentration of solutes outside the cell causes water to exit the cell, attempting to equalize the solute concentration on both sides.

💡Osmosis

Osmosis is the movement of water across a semipermeable membrane from an area of lower solute concentration to an area of higher solute concentration. The video explains that osmosis is driven by the concentration gradient, and it's the movement of water, not solutes. It's illustrated with the example of a red blood cell in an isotonic solution, where water moves freely in and out of the cell, maintaining its size.

💡Isotonic Solution

An isotonic solution is one where the concentration of solutes outside the cell is equal to the concentration inside the cell. The video describes isotonic solutions as having the same strength, leading to equal amounts of water entering and exiting the cell, thus maintaining the cell's size. This is the ideal condition for animal cells, as it allows for normal cellular function without the cell swelling or shrinking.

💡Hypertonic Solution

A hypertonic solution has a higher concentration of solutes per solvent than what is found inside the cell. The video explains that when a cell is placed in a hypertonic solution, more water exits the cell to dilute the higher concentration of solutes outside, causing the cell to shrivel or shrink. This is a critical concept as it demonstrates the effect of external solute concentration on cell volume.

💡Hypotonic Solution

A hypotonic solution has a lower concentration of solutes than what is found inside the cell. The video describes that in a hypotonic solution, water rushes into the cell to equalize the solute concentration, causing the cell to swell. In the case of animal cells, this can lead to lysis, or bursting of the cell, while plant cells can withstand the pressure due to their rigid cell walls, leading to a state called turgor.

💡Solute

A solute is a substance that is dissolved in a solvent to form a solution. In the video, solutes are represented by the green particles, and their movement across the cell membrane is central to the discussion of diffusion. The concentration of solutes in different solutions (isotonic, hypertonic, hypotonic) directly affects the movement of water and the state of the cell.

💡Solvent

A solvent is a substance, usually a liquid, that dissolves other substances (solutes) to form a solution. Water is the most common solvent, as mentioned in the video, and it's the medium through which solutes move. The video uses the example of Kool-Aid powder dissolving in water to illustrate the concept of a solvent.

💡Lysis

Lysis refers to the bursting or breaking of a cell, typically due to an influx of water causing the cell to swell beyond its structural limits. In the video, lysis is used to describe what happens to animal cells placed in a hypotonic solution, where the rush of water into the cell causes it to explode, as demonstrated in the example of blood cells.

💡Turgidity

Turgidity is the state of a cell being rigid and firm due to being filled with water. The video explains that in plant cells, when placed in a hypotonic solution, the cell wall prevents the cell from bursting, and instead, the cell becomes turgid, which is a normal state for plant cells. This turgid state allows plant cells to maintain their structure and reach for sunlight effectively.

💡Plasmolysis

Plasmolysis is the process where plant cells lose water in a hypertonic solution, causing the cell membrane to pull away from the cell wall. The video describes plasmolysis as the plant cell equivalent of shriveling, where the cell loses water to the hypertonic environment, leading to a decrease in cell volume and a separation of the cell contents from the cell wall.

Highlights

Materials move across membranes due to concentration differences.

Concentration gradient drives the movement of water or solute across a membrane.

Movement of solute is called diffusion, and movement of water is called osmosis.

A solution is formed when a solute dissolves in a solvent.

Water is the most common solvent in solutions.

Isotonic solutions have equal solute concentration inside and outside the cell.

In isotonic conditions, red blood cells maintain a constant size as water moves equally in and out.

Hypertonic solutions have a higher solute concentration outside the cell.

Cells placed in hypertonic solutions lose water, leading to cell shrinkage.

Hypotonic solutions have a lower solute concentration outside the cell.

Cells in hypotonic solutions take in water, which can cause them to swell or burst.

Animal cells in hypotonic solutions can lyse, or explode due to water intake.

Animal cells in isotonic solutions have normal water movement and maintain their shape.

Plant cells in hypotonic solutions become turgid due to increased water intake.

Plant cells in isotonic solutions are flaccid, which is not ideal for plant health.

Plant cells in hypertonic solutions undergo plasmolysis, where they lose water and shrivel.

Visual representation of blood cells lysing in hypotonic solution is provided.

Transcripts

hey it's Mr veev and this lesson is on

types of solutions so let's get into our

first key concept here materials move

across membranes because of

concentration differences so we've

already learned about a concentration

gradient and how that drives whether

water or solute moves back and forth

across a membrane remember movement of

solute is called diffusion and movement

of water is called osmosis so let's look

at three different types of solutions

and first we're going to discover what a

solution is so a solution is a solute

that dissolves in a solvent to form a

solution so in the picture here you can

see that the Kool-Aid looking stuff

there is the solution and in this case

if it was Kool-Aid the solute would be

the Kool-Aid powder and the solvent

would be water water in most cases is

the solvent in almost all solutions that

we're going to look at today so the

three types of solutions we're going to

start with are isotonic okay so ISO

means same tonic means strength this is

same strength solution is said to be

isotonic if the uh concentration of

solute outside the cell and inside the

cell is equal so you can see there in

the picture that we have an equal number

of those green particles the solute

inside and outside the cell so both

inside and outside is the same strength

so let's look at what that see we see a

red blood cell here and isotonic would

mean equal amounts of water are entering

and exiting the cell so the size of that

cell is going to stay constant over a

certain period of time so water moving

in water moving out no problems there so

let's talk about a hypertonic hyper is

more tonic is strength so this is a a

more concentrated solution here so a

solution is hypertonic if it has more

solute per solvent uh than a cell so as

you can see on the outside of the cell

here there's a lot of these green

particles and fewer of them on the

inside of the cell so think of those

maybe as salt or something like that the

uh the saltiness on the outside is a lot

more than the inside of the cell so what

does that H what does that do to the

cell so if the solution on the outside

of the cell is hypertonic it's high high

concentration more water is going to

want to exit the cell and that causes

the cell to shrivel up the water is

exiting that cell and trying to dilute

that hypertonic solution on the outside

to make both the inside and the outside

of the cell equal all right so that's

what's going to happen in a hypertonic

solution when you put a cell in there so

now the last one is hypotonic that is

less strength so a solution is hypotonic

if it has fewer solute um than a cell so

you see there in the picture we've got a

tiny amount of solute on the outside

with a lot more on the inside so what do

you think is going to happen here well

if you have a cell put in a hypotonic

solution there is more solute in the

cell than there is outside so therefore

water is going to want to rush into the

cell to make those Sol Solutions equal

that's going to actually cause the cell

to swell or even burst in some cases and

we'll look at that in just a minute so

if we look at three different uh types

of solutions here hypo hyper and

isotonic and their effects on animal and

plant cells let's go uh from left to

right here starting with the top so if

you have a cell and you place it in a

hypotonic solution water is going to

rush into the cell and cause it to lice

which means explode okay if you have an

isotonic solution and you put an animal

cell in there it's going to be a normal

in andout of water so everything's fine

water's going to freely go in and out

nothing's going to happen to the cell

that's normal if you put an animal cell

in a hypertonic solution meaning there's

a lot of solute on the outside water is

going to end up leaving the cell to

dilute that uh Solution on the outside

so therefore the cell is going to shrink

up or become shrivel now the normal

conditions for an animal cell is it

wants to be in an isotonic solution

um plant cells are a little bit

different so plant cells um when they

are in a hypotonic solution they get

filled up with water and they don't

actually burst the cell wall actually

holds it uh pretty well there's an

increase in what's called turer pressure

so the the cell is what's called turgid

and that's normal for the cell uh the

more turer pressure meaning the the more

the the cell is full of water and the

more expanded the cell walls are the

better it can uh reach for sunlight or

or things like that um if you put a

plant cell in an isotonic solution

you're going to have water moving in and

out freely you're not going to hold on

to as much water as the plant wants to

and so we would call that a flaccid cell

so that is not ideal for the plant

that's what plants look like when they

begin to wilt just a little bit uh

finally for plant cells if you put them

in a hypertonic solution well of course

that water is going to rush out and it's

not going to what we call shrivel it's

going to uh plasm uh same same basic

principle as shriveling it's going to

have far less water on the inside and

it's basically going to shrivel but

that's called plasmolysis in plant

cells so finally here I have a little uh

picture here for you of a blood cell

going through Lis so those blood cells

they are actually put into a hyp

hypotonic solution waterers rushing into

the cells causing them to explode that's

actually what it looks like under a

microscope and ignore the fact that

distilled water is misspelled on the

bottom left