The Cell Membrane
Summary
TLDRThis video explores the cell membrane, focusing on the fluid mosaic model, which describes its fluid nature and diverse components like phospholipids, proteins, glycoproteins, and cholesterol. It delves into the amphipathic nature of phospholipids, the roles of different proteins, and how substances like water, ions, and glucose move across the membrane, highlighting the importance of cholesterol in maintaining membrane fluidity.
Takeaways
- 𧬠The cell membrane is described by the fluid mosaic model, which highlights its fluid nature and the ability of its components to move freely.
- π¬ The membrane is composed of various components including phospholipids, proteins, glycoproteins, glycolipids, and cholesterol, each playing a distinct role.
- π΄ Phospholipids are the primary constituents of the cell membrane, featuring a polar head and nonpolar tails, making them amphipathic.
- π The dual polarity of phospholipids, with hydrophilic heads and hydrophobic tails, contributes to the formation of the phospholipid bilayer in the cell membrane.
- π Proteins in the cell membrane can be categorized as peripheral, integral, or transmembrane, each with different functions and interactions with the membrane.
- π Glycoproteins and glycolipids are involved in cell interactions and signaling, and play crucial roles in the immune system and cell recognition.
- π The cell membrane is semi-permeable, allowing certain molecules like small nonpolar molecules and water to pass through, but requiring transport proteins for ions and larger molecules.
- π° Aquaporins are integral proteins that facilitate the efficient transport of water across the cell membrane, crucial for maintaining cellular hydration.
- π Cholesterol acts as a buffer in the cell membrane, maintaining its fluidity by preventing phospholipids from moving too far apart or too close together, thus aiding in homeostasis.
- π₯ The fluidity of the cell membrane is influenced by temperature, with increased temperature leading to increased fluidity, and cholesterol playing a role in regulating this process.
Q & A
What is the fluid mosaic model and how does it describe the cell membrane?
-The fluid mosaic model is a concept that describes the structure of the cell membrane. It suggests that the membrane is fluid, allowing phospholipids and proteins to move freely in any direction within the membrane. The term 'mosaic' refers to the variety of components that make up the membrane, including phospholipids, proteins, glycoproteins, glycolipids, and cholesterol.
What are the main components of the cell membrane?
-The main components of the cell membrane include phospholipids, proteins, glycoproteins, glycolipids, and cholesterol. Phospholipids form the bilayer structure of the membrane, while proteins can be integral or peripheral, with some spanning the entire membrane (transmembrane proteins) and others embedded within or associated with the surface of the membrane.
What is the dual polarity nature of a phospholipid?
-A phospholipid has a dual polarity nature, meaning it has both hydrophobic (water-fearing) and hydrophilic (water-loving) parts. The hydrophobic tails are composed of fatty acid chains, while the hydrophilic head contains a phosphate group. This amphipathic nature allows phospholipids to form the bilayer structure of the cell membrane, with the hydrophobic tails facing away from water and the hydrophilic heads facing towards water.
How do proteins function within the cell membrane?
-Proteins in the cell membrane serve various functions. Some are integral proteins that are embedded within the membrane, while others are transmembrane proteins that span the entire membrane. They can act as channels for ions, carrier proteins that transport larger molecules like glucose, or as enzymes to speed up chemical reactions. Surface proteins can be involved in cell signaling and interactions.
What is the role of cholesterol in the cell membrane?
-Cholesterol plays a crucial role in maintaining the fluidity of the cell membrane. It has both polar and nonpolar regions, with the polar region facing outward and the nonpolar region interacting with the hydrophobic tails of phospholipids. Cholesterol acts as a buffer, preventing the membrane from becoming too fluid or too rigid by spacing the phospholipids appropriately in response to temperature changes.
How does the cell membrane control the passage of substances?
-The cell membrane is semi-permeable, allowing certain substances to pass through while blocking others. Small nonpolar molecules like oxygen and carbon dioxide can diffuse easily across the membrane. Water, being a small polar molecule, can also diffuse but at a slower rate due to its interaction with the nonpolar interior of the membrane. Ions and larger polar molecules require transport proteins, such as channel proteins and carrier proteins, to move across the membrane.
What are aquaporins and what is their function?
-Aquaporins are special proteins that facilitate the transport of water molecules across the cell membrane. They increase the efficiency of water movement, allowing water to pass through the membrane more easily than it would by simple diffusion alone.
What is the difference between a glycoprotein and a glycolipid?
-A glycoprotein is a molecule where a carbohydrate (sugar) chain is attached to a protein, often found on the surface of cellular membranes and plays a role in cell recognition and immune system functions. A glycolipid, on the other hand, has a carbohydrate attached to a phospholipid and is also involved in cell interactions and signaling.
How does the cell membrane maintain homeostasis through cholesterol?
-The cell membrane maintains homeostasis through cholesterol byθ°θ the fluidity of the membrane. As temperature increases, cholesterol helps to decrease fluidity by preventing phospholipids from moving apart. Conversely, when the temperature decreases and the membrane becomes more rigid, cholesterol acts as a spacer to increase fluidity, thus maintaining the membrane's stability and function.
What is the function of the sodium-potassium pump mentioned in the script?
-The sodium-potassium pump is an example of an ion channel protein that helps to maintain the electrochemical gradient across the cell membrane by actively transporting sodium ions out of the cell and potassium ions into the cell. This process is crucial for nerve signal transmission and muscle contraction, among other functions.
How does the presence of unsaturated phospholipids affect the fluidity of the cell membrane?
-The presence of unsaturated phospholipids, which contain double bonds causing kinks in their fatty acid chains, increases the fluidity of the cell membrane. These kinks prevent the fatty acid chains from packing tightly together, allowing for greater movement and flexibility within the membrane.
Outlines
𧬠Introduction to the Cell Membrane
This paragraph introduces the cell membrane and its components. The fluid mosaic model is discussed, highlighting the fluid nature of the membrane, allowing phospholipids and proteins to move freely. The model also emphasizes the membrane's composition of phospholipids, proteins, glycoproteins, glycolipids, and cholesterol. Phospholipids, with their polar heads and nonpolar tails, are the primary focus, described as amphipathic molecules that form the bilayer of the cell membrane. The role of proteins, including globular and surface proteins, is also touched upon, with a distinction made between integral and transmembrane proteins.
π Proteins and Their Functions in the Cell Membrane
This paragraph delves deeper into the types of proteins found in the cell membrane, such as surface proteins and integral proteins. Surface proteins can be anchored to the cytoskeleton, functioning as enzymes or playing a role in the immune system. Glycoproteins, which are proteins with attached sugar chains, are highlighted for their role in cell interactions and immune system recognition. Glycolipids, which have sugar units attached to phospholipids, are also mentioned in the context of cell signaling. The paragraph further discusses the semi-permeable nature of the cell membrane, allowing certain molecules to pass through while blocking others, and the role of aquaporins in water transport across the membrane.
π° Transport Mechanisms Across the Cell Membrane
This paragraph focuses on how substances move across the cell membrane. Small nonpolar molecules like oxygen and carbon dioxide can easily diffuse, while water, being a small polar molecule, can diffuse but at a slower rate due to its interaction with the nonpolar interior. Special proteins called aquaporins facilitate water transport. Ions and large polar molecules like glucose require transport proteins to cross the membrane. Channel proteins, such as ion channels, and carrier proteins are discussed, with the sodium-potassium pump given as an example of how ions are transported.
π‘οΈ Cholesterol's Role in Membrane Fluidity
This paragraph discusses the role of cholesterol in the cell membrane. Cholesterol has both polar and nonpolar regions, with the polar region facing outward and the nonpolar region facing inward. Cholesterol acts as a buffer, maintaining the membrane's fluidity. As temperature increases, the membrane becomes more fluid, and cholesterol helps prevent the phospholipids from moving too far apart. Conversely, when the temperature decreases, cholesterol acts as a spacer to prevent the membrane from becoming too rigid. This function of cholesterol is crucial for maintaining homeostasis in the cell.
π Review and Practice Questions on Cell Membrane Components
This paragraph reviews the key components of the cell membrane and poses practice questions to reinforce understanding. It covers the amphipathic nature of phospholipids, their role as the major components of the cell membrane bilayer, and the false statement regarding their composition. The paragraph also addresses which particles cannot pass through the cell membrane without transport proteins, highlighting the need for channel proteins and carrier proteins for ions and large polar molecules like glucose. The distinction between surface proteins, globular proteins, transmembrane proteins, and integral proteins is clarified through additional questions.
π‘οΈ Factors Affecting Membrane Fluidity and Summary
This paragraph explores factors that affect the fluidity of the cell membrane, such as temperature and the composition of phospholipids. It explains that increasing temperature generally increases membrane fluidity, while cholesterol helps maintain a balance. The paragraph also discusses the impact of saturated versus unsaturated phospholipids on fluidity. Finally, it provides a series of matching problems to review concepts like semi-permeable membranes, aquaporins, the fluid mosaic model, ion channels, cholesterol, glycoproteins, glycolipids, integral proteins, transmembrane proteins, carrier proteins, and peripheral proteins.
Mindmap
Keywords
π‘Fluid Mosaic Model
π‘Phospholipids
π‘Proteins
π‘Glycoproteins
π‘Glycolipids
π‘Cholesterol
π‘Semi-permeable
π‘Aquaporins
π‘Transmembrane Proteins
π‘Integral Proteins
π‘Carrier Proteins
Highlights
Introduction to the cell membrane and its components.
Explanation of the fluid mosaic model of the cell membrane.
Description of the fluid nature of the membrane allowing phospholipids and proteins to move freely.
Identification of membrane components including phospholipids, proteins, glycoproteins, glycolipids, and cholesterol.
Detailed structure of a phospholipid with a polar head and nonpolar tails.
The amphipathic nature of phospholipids and their role in forming the phospholipid bilayer.
Differentiation between globular and surface proteins and their locations on the cell membrane.
Explanation of integral and transmembrane proteins and their functions.
Role of surface proteins in cell signaling and their potential anchoring to the cytoskeleton.
Function of glycoproteins in the immune system and cell interactions.
The role of glycolipids in cell signaling and tissue recognition.
Semipermeability of the cell membrane and the diffusion of small nonpolar molecules like oxygen and carbon dioxide.
Importance of aquaporins in facilitating water diffusion across the cell membrane.
Necessity of transport proteins like ion channels for ions to pass through the membrane.
The role of carrier proteins in transporting large polar molecules like glucose across the membrane.
Cholesterol's function as a fluidity buffer in maintaining the cell membrane's fluidity.
Impact of temperature on membrane fluidity and cholesterol's role in temperature regulation.
Practice problems to reinforce understanding of cell membrane components and functions.
Summary of the key points covered in the video about the cell membrane.
Transcripts
in this video we're going to talk about
the cell membrane and we're going to
identify the components that make up
that membrane
now the first thing we're going to do is
talk about something known as the fluid
mosaic model
so this model describes
the cell membrane
it tells us that the membrane is fluid
which means that
the phospholipids are free to move
in any direction in this membrane even
the proteins highlighted in purple
they're also fluid they can move about
in this membrane as well
the word mosaic tells us that this
picture
is composed of many different parts
the membrane is composed of
phospholipids
proteins glycoproteins glycolipids
cholesterol and things like that so
there's many different parts that make
up the cell membrane
but the first component we're going to
talk about
is the phospholipid in red
the membrane is mostly composed of
phospholipids
the phospholipid has a polar head
and two
nonpolar cells
so keep in mind the phospholipid is
composed of
a phosphate group
it has two fatty acid chains
and it also has a glycerol molecule
the two fatty acid cells are nonpolar
which means that they're hydrophobic
they don't like water
the polar head is hydrophilic it loves
water
water
exists in the extracellular fluid
outside of the cell
and it also is present in the
intracellular space that is inside of
the cell
so all of the phospholipids the polar
heads are faced toward water the
nonpolar tails are faced away from water
in the interior of the cell membrane
now here's a question for you
what word
describes
the dual polarity nature of a
phospholipid
we said that a phospholipid has a polar
hydrophilic head
and two
nonpolar hydrophilic tails
there's a word that describes a molecule
with hydrophobic and hydrophilic parts
what word is that
that word is amphipathic
phospholipids are amphipathic
because they're both hydrophobic and
hydrophilic
so they make up the phospholipid bilayer
of the cell membrane
so that's the first component of the
cell membrane that you need to be
familiar with
now the cell membrane is consists of
a lot of proteins
and there's different types of proteins
they're highlighted in purple
what do you call this protein right here
so if you see a circular protein it's
known as
a globular protein
and the fact that it's on the exterior
it's also called
a peripheral
protein
this protein here is known as a surface
protein because it's on the surface
of the phospholipid
bilayer
now
how would you distinguish these two
proteins
what would you say
by the way this is another peripheral
protein
but it's not a globular protein
now
how would you distinguish between an
integral protein and a trans membrane
protein
this protein here is known as
a trans membrane protein i'm just going
to put tmp for that since i'm running
out of space a transmembrane protein
spans
across
the membrane so as you can see part of
it is outside of the membrane and the
rest of it is inside of the membrane
this here is called
an integral protein
an integral protein is embedded within
the membrane
now a transmembrane protein is also an
integral protein
because
for them to
span the entire membrane they also have
to be within the membrane as well
so all transmembrane proteins are
integral proteins
but not all integral proteins are
transmembrane proteins
so as we said before this is both a
transmembrane protein and an integral
protein but this right here is an
integral protein and not a transmembrane
protein
now i had to clear away a few things
because
the page was getting crowded
now one thing i do want to mention is
you could also have a surface protein on
the inside of a cell
but it's on the surface of the membrane
and some of these surface proteins
they could be anchored
to the cytoskeleton network of the cell
through filaments
now some of the
surface proteins and also the perfume
proteins
they could function as enzymes
so they can speed up chemical reactions
within the cell as well
now
here's another question for you what's
the difference
between these two structures there
what are they called
so here we have a protein
attach to a sugar chain
those hexagonal shapes represents
the six carbon
glucose unit
so we have a carbohydrate attached to a
protein
so this is called a glycoprotein
many glycoproteins which are found on
the surface of cellular membranes
they play a role in the immune system
with antibodies they function as a self
recognition and
cell to cell interactions
now over here
notice that we have
a sugar unit attached to a phospholipid
so in this case this would be
a glycolipid
which also plays a role in cellular cell
interactions and cell signaling
now the next thing we're going to talk
about
is how things flow into and out of the
membrane
the cell membrane is semi-permeable
which means it allows certain things to
get in
while blocking other things or prevent
other things from entering the cell
now small nonpolar molecules can easily
diffuse into or out of the cell
so when you take a breath when you
breathe in you're breathing in o2
oxygen
flows into the cell because the cell
needs it and then when you exhale you
breathe out carbon dioxide so carbon
dioxide tends to flow out of the cell
so both of these molecules
are nonpolar small molecules they can
easily
pass in and out of the cellular membrane
now water
is a small polar molecule and it turns
out that water
can diffuse
through the membrane
but
it can't do it easily it's a very slow
process because water is polar
and it doesn't
mix well with the nonpolar interior
region however because the concentration
of water is so high inside and outside
of the cell some of it will force its
way through the cellular membrane
but now there are special proteins
that can easily
transport water
into and out of the cell
and these are called aquaporins
so this protein right here this integral
protein also serves as a protein that
transports stuff
a protein that transports water through
the membrane as you said before
aquaporins
water can flow into or out of
you know that protein
so if you drink a glass of water
water is going to flow into your cells
if it's a hot day and you're jogging and
you're sweating you're dehydrated
water's flowing out of your cells so
water can go in either direction
now what about other
particles let's say like an ion
potassium and sodium
can they flow into and out of the
cellular membrane
now ions
they can't flow
in and out of the cellular membrane
without the help of a transport protein
so they can't just pass through the
membrane
their charges are significantly greater
than water water is neutral but it has
partial charges which makes it polar
ions have a complete full positive or
negative charge
so they just can't flow through the
membrane
without the help of a transport protein
so the protein that they need is called
a channel protein specifically it's
known as ion channels
so the ion channels will help sodium and
potassium to flow either into or out of
the cell
one example is the sodium potassium pump
which i'm not going to go
into detail into this video
so
integral proteins they could serve as
channel proteins they could serve as
carrier proteins
and things like that
now this right here is an example of a
carrier protein
let's say if you have a big molecule
like glucose
the carrier protein can
take in glucose
and then this part can close
this part
will open
and then glucose will travel through
glucose is a big polar molecule it can't
simply diffuse
through the membrane so it needs the
help of a carrier protein to get it
across the membrane
so just to review
small molecules like oxygen carbon
dioxide water they can diffuse
through the membrane for what it's a
little bit difficult
big molecules like glucose
big polar molecules
they can't diffuse through the cell and
ions like sodium potassium they can't
diffuse across the membrane without the
help of a protein
now there's one more thing that we need
to talk about
regarding the cell membrane another
important component and that is
cholesterol
which is right here
now cholesterol has
a polar region and a nonpolar region
the circle in blue is the hydroxyl group
of the cholesterol molecule
and the hydroxyl group is polar because
of hydrogen bonding
it's very attracted to water
and so it's going to be
facing
outside of the cellular membrane
now the four fuse rings of cholesterol
and that's the nonpolar region the
hydrophobic region
and so that's going to be pointing
towards the interior
of the membrane
now the function of cholesterol in the
membrane is very important cholesterol
acts as a buffer
it maintains
the fluidity of the membrane
here's a question for you
if you increase the temperature
what happens to the membrane
will it become more fluid or less fluid
will the phospholipids
will they move apart from each other
or
will they move closer to each other
now let's think of water
at room temperature water is fluid
if you decrease the temperature let's
say if you put it in a freezer it's
going to turn to ice it's not going to
be fluid anymore so whenever you
increase the temperature
you increase the fluidity of a material
now
as you increase the temperature of the
cellular membrane
the phospholipids will move apart from
each other and so they will become more
fluid
cholesterol
it functions to maintain a fluid
so it's going to try to
decrease the fluidity
and so what it does is
it kind of prevents the phospholipids
from moving apart from each other so
that the cell membrane just doesn't
dissolve
now if we decrease the temperature
the fluidity of the membrane will
decrease it will become more rigid
cholesterol
will act to prevent that it's going to
try to increase the fluidity so it acts
as a spacer
so these phospholipids when the
temperature goes down they want to get
closer and so what happens is
cholesterol prevents them from getting
too close
so whenever the fluidity goes up
cholesterol tries to bring it down when
the fluidity goes down cholesterol tries
to bring it up so it maintains the
fluidity
of the cell
so it's another example of homeostasis
or equilibrium
so that's the function of cholesterol
in the cell membrane
now let's work on some practice problems
just to review some of the things that
we covered early in this video
number one
which of the following statements is not
true
concerning phospholipids
would you say a
phospholipids are amphipathic
b
phospholipids contain a hydrophilic head
c
the tails of a phospholipid point toward
the interior of the cellular membrane
d phospholipids are the major components
of the cell membrane bilayer or e
phospholipids contain a phosphate group
three fatty acetals and the glycerol
molecule
so which of these statements is not true
or which one is false
so let's go through each one
this is a true statement
phospholipids are
amphipathic
they contain a hydrophilic polar head
and the tails
are hydrophobic
so answer choice a is the true statement
b
phospholipids contain a hydrophilic head
that is also true as you can see that
here
and for c
the tails of a phospholipid point toward
the interior of the cellular membrane
that is also true
the membrane looks like this
and as you can see the tails are
definitely in the interior of the
membrane
now for antichoice d
phospholipids are the major components
of the cell membrane bilayer that is
definitely a true statement
the only thing that's false is e
phospholipids do contain a phosphate
group
and they contain a glycerol molecule
but they don't have three fatty acid
cells
they only have two
and so that's why e is not true
number two
which of the following particles cannot
pass through the cell membrane without
the assistance of a transport protein
so we're going to circle each one
because there can be multiple answers
so let's say
this is
the cell membrane
can water pass through the cell membrane
what would you say
now it's not that easy but because
there's a lot of water inside and
outside the cell the human body is
mostly composed of water
it can
fit through it it's very small
so water can pass through the cell
membrane
so this is not what we're looking for
now what about the potassium ion can
that pass do it
ions
are not able
to go through the membrane
they can't get to this hydrophobic
region
so
b is one of the answers that we're
looking for
nonpolar molecules like o2
this can easily diffuse in the cell
membrane
and carbon dioxide which is another
nonpolar molecule that can that can
easily diffuse out of the membrane
out of the cell into the extracellular
fluid
so we can eliminate anti-choice c and d
now glucose
glucose can't diffuse
through the membrane without the
assistance of a transport protein
so glucose it needs a carrier protein to
get through the membrane
so e would also be an answer so it's
both b and e
ions and big polar molecules like
glucose
and they need a transport protein to
pass through the membrane
number three
which of the following proteins span
across the entire cell membrane
is it a surface proteins
b
the globular proteins c
transmembrane proteins
d
integral proteins or e carrier proteins
what would you say
so let's say this is the cell membrane
so this would be a surface protein
this would be a globular protein
and it's also a peripheral protein
because it sticks out of
the membrane but doesn't pass through it
this would be
an integral protein
and this would be
a transmembrane protein
the best answer
is the transmembrane protein
this it spans across the entire cell
membrane
the integral protein
it's simply embedded within the cell
membrane
now keep in mind all transmembrane
proteins are integral proteins but not
all integral proteins are transmembrane
proteins
and carrier proteins as we mentioned in
the video they simply
carry stuff across the cell membrane
so this is really not the best
description of a transmembrane protein
they could be transplanting proteins
they could be integral proteins but
this answer is the best answer
number four
which of the following molecules act as
a fluidity buffer in the cellular
membrane
is it cholesterol aquaporins ion
channels glycoproteins or glycolipids
it's not going to be aquaporins keep in
mind these are proteins
that can carry water across the membrane
it's not going to be ion channels ion
channels are protein channels that carry
ions like potassium and sodium
across the cell membrane
and it's not going to be glycoproteins
so these
exist on the surface of the cell and
it's not going to be glycolipids
the answer is cholesterol
so keep in mind as the temperature goes
up
the fluidity of the membrane goes up the
phospholipids move apart
but cholesterol
kind of anchors the phospholipids
together so prevents them from moving
apart thus maintaining the fluidity
so whenever the temperature goes up
cholesterol tries to decrease the
fluidity of the membrane
under colder conditions
the membrane becomes more rigid
cholesterol acts as a spacer increasing
the fluidity of the membrane
so cholesterol maintains the fluidity of
the membrane
now here's another question for you
number five
which of the following can increase the
fluidity of the cellular membrane
so number one we've already covered this
we know that increasing
the temperature
will increase the fluidity of the
membrane so number one is a true
statement
what about number two increasing the
number of saturated phospholipids
will that increase or decrease
the fluidity of the cellular membrane
well let's talk about saturated fatty
acids
a saturated fatty acid if you recall
has no double bonds
and these
tend to be solid at room temperature
now an unsaturated fatty acid
they do carry double bonds and this
creates a kink in the structure
so these type of fatty acids tend to be
liquid
or oils at room temperature
so you need to understand that saturated
fatty acids
and saturated phospholipids
they tend to be
more rigid
whereas the unsaturated phospholipids
will have more fluidity
they're going to be more liquid
so the correct answer
will be
increasing the number of unsaturated
phosph excuse me increase the number of
unsaturated phospholipids that's going
to increase the fluidity if you increase
the number of saturated phospholipids
that will decrease the fluidity
so number two is false
the answer is going to be one and three
which is ants choice b
so this will be an example of a
saturated
phospholipid because
both of the fatty acids
they're straight
this is an example of an unsaturated
phospholipid
as you can see one of the fatty acid
chains has a kink in the structure which
means it has a double bond
so if you have more of these
phospholipids
the membrane is going to be more fluid
phospholipids of this nature
will create a membrane that's more rigid
and less fluid
now let's work on some matching problems
feel free to pause the video
and
work out these questions
for the sake of a review
so let's go ahead and begin number one
so this allows some molecules to pass
through while preventing others from
doing so
so which word best describes that
sentence
so the answer for this
would be a semi-permeable
membrane it allows certain molecules to
pass through the membrane while
preventing others from doing so
number two
so which word goes with this sentence
it allows water to pass through the
membrane efficiently
so this would be
an aquaporin
number three
this explains how phospholipids and
proteins
are free to move in the cell membrane
so this is going to be
the fluid mosaic model
so
we're going to put letter i for number
three number four
this allows particles like potassium and
sodium ions to pass through the membrane
so this is going to be
ion channels
so let's put g for number four
number five
this maintains the fluidity of the cell
membrane
so this is going to be cholesterol
so let's put b for five number six
and this molecule plays
this should be plays a role
in cell communication and
self-recognition in the immune system
what molecule is that
this is going to be the glycoproteins
so that's a d
number seven
an amphipathic molecule that makes up
the cell membrane bilayer
which one is that
so the answer is going to be l
phospholipids are amphipathic
they contain hydrophobic and hydrophilic
parts to themselves and they make up
the phospholipid bilayer of the cell
membrane
number eight
so this plays a role in cell signaling i
said that wrong cell signaling and
tissue recognition
so this is going to be the glycolipids
and number nine
this macromolecule is completely
embedded within the lipid layer i mean
the lipid bilayer
my words is just not coming out right
today
so this is going to be uh the integral
proteins
they're completely integrated
in the lipid bilayer
number 10
this molecule completely spans through
the membrane
so this is going to be the transmembrane
protein
so that's c
number 11
this component transports
molecules across
the membrane
so that's going to be the carrier
protein that's h
and 12 this molecule lies on the
exterior of the cell membrane
which is f
the peripheral proteins
surface proteins also lie on the
exterior of the cell membrane
but the peripheral proteins
part of it is
inside the membrane and part of it is
outside of the membrane but it doesn't
span completely through the membrane
so that's basically it for this video
that's an introduction into the cell
membrane thanks again for watching and
if you like it
don't forget to subscribe to this
channel
5.0 / 5 (0 votes)