The plasma membrane is the outermost layer of the cell that is selectively permeable and separates the internal cell components from the external environment. It has a bilayer structure composed of phospholipids, proteins, and carbohydrates. The fluid mosaic model describes the plasma membrane as a flexible lipid bilayer with embedded proteins that move laterally within the bilayer. Materials can pass through the membrane via passive diffusion, facilitated diffusion using membrane protein channels, or active transport against the concentration gradient using membrane pumps that require cellular energy. Large particles enter and exit the cell through endocytosis and exocytosis using membrane vesicles.
The cell membrane (also known as the plasma membrane or cytoplasmic membrane) is a biological membrane that separates the interior of all cells from the outside environment. The cell membrane is selectively permeable to ions and organic molecules and controls the movement of substances in and out of cells.The basic function of the cell membrane is to protect the cell from its surroundings. It consists of the phospholipid bilayer with embedded proteins. Cell membranes are involved in a variety of cellular processes such as cell adhesion, ion conductivity and cell signalling and serve as the attachment surface for several extracellular structures, including the cell wall, glycocalyx, and intracellular cytoskeleton.
The cell membrane (also known as the plasma membrane or cytoplasmic membrane) is a biological membrane that separates the interior of all cells from the outside environment. The cell membrane is selectively permeable to ions and organic molecules and controls the movement of substances in and out of cells.The basic function of the cell membrane is to protect the cell from its surroundings. It consists of the phospholipid bilayer with embedded proteins. Cell membranes are involved in a variety of cellular processes such as cell adhesion, ion conductivity and cell signalling and serve as the attachment surface for several extracellular structures, including the cell wall, glycocalyx, and intracellular cytoskeleton.
This presentation is all about cell membrane transport. It contain different ways of transport of different substances in and out of cell membrane, along with active and passive mechanism.
"Plasma membrane structure and function"
Presented by :
Jitul Kalita
Department of biotechnology,
Pandu College, Guwahati, Assam
jitulkalitaown@gmail.com
The structure of the cell membrane, the phospholipid layer distinguished to the break down of protein and the lipid layer. Their structural components and the molecular basis of it.
this presentation contain the basic introduction of CCVs.
who discover this?
what are the structure of CCVs?
role of CCVs
advantage and their fuctions.
General overview of Plasma/ Cell membrane.
Definition of Plasma/ Cell membrane
Structure of Plasma membrane
1. Sandwitch model OR Danielli- Davson Model
2. Fluid mosaic model
Plasma Membrane Proteins
Chemical Composition of Plasma/ Cell Membrane
Movement across the Cell Membrane
Channels through cell membrane
The plasma membrane, also called the cell membrane, is the membrane found in all cells that separates the interior of the cell from the outside environment. . The plasma membrane consists of a lipid bilayer that is semipermeable. The plasma membrane regulates the transport of materials entering and exiting the cell.
This presentation is all about cell membrane transport. It contain different ways of transport of different substances in and out of cell membrane, along with active and passive mechanism.
"Plasma membrane structure and function"
Presented by :
Jitul Kalita
Department of biotechnology,
Pandu College, Guwahati, Assam
jitulkalitaown@gmail.com
The structure of the cell membrane, the phospholipid layer distinguished to the break down of protein and the lipid layer. Their structural components and the molecular basis of it.
this presentation contain the basic introduction of CCVs.
who discover this?
what are the structure of CCVs?
role of CCVs
advantage and their fuctions.
General overview of Plasma/ Cell membrane.
Definition of Plasma/ Cell membrane
Structure of Plasma membrane
1. Sandwitch model OR Danielli- Davson Model
2. Fluid mosaic model
Plasma Membrane Proteins
Chemical Composition of Plasma/ Cell Membrane
Movement across the Cell Membrane
Channels through cell membrane
The plasma membrane, also called the cell membrane, is the membrane found in all cells that separates the interior of the cell from the outside environment. . The plasma membrane consists of a lipid bilayer that is semipermeable. The plasma membrane regulates the transport of materials entering and exiting the cell.
Plasma membrane or plasma-lemma or cell membrane
Plasma membrane can be defined as a biological membrane or an outer membrane of a cell, which is composed of two layers of phospholipids and embedded with proteins. It is a thin semi permeable membrane layer, which surrounds the cytoplasm and other constituents of the cell.
Occurs on the outside of the cytoplasm in both prokaryotes and eukaryotic cells.
It separates the cellular protoplasm from its external environment.
Structure and function of plasma membrane 2ICHHA PURAK
The presentation consists of 72 slides,describes following heads
DEFINITION : STRUCTURE OF PLASMA MEMBRANE
COMPONENTS OF PLASMA MEMBRANE ( (BIOCHEMICAL PROPERTIES)
LIPID BILAYER
PROTEINS
CARBOHYDRATES
CHOLESTEROL
MODELS EXPLAINING STRUCTURE OF BIO MEMBRANE
FLUID MOSAIC MODEL
MOBILITY OF MEMBRANE
GLYCOCALYX : GLYCOPROTEINS AND GLYCOLIPIDS
TRANSPORT OF IONS AND MOLECULES ACROSS PLASMA MEMBRANE
FUNCTIONS OF PLASMA MEMBRANE
DIVERSITY OF CELL MEMBRANES
SITE OF ATPASE ION CARRIER CHANNELS AND PUMPS-RECEPTORS
prof . dr. ihsan edan alsaimary
department of microbiology - college of medicine - university of basrah - basrah -IRAQ
ihsanalsaimary@gmail.com
00964 7801410838
Operation “Blue Star” is the only event in the history of Independent India where the state went into war with its own people. Even after about 40 years it is not clear if it was culmination of states anger over people of the region, a political game of power or start of dictatorial chapter in the democratic setup.
The people of Punjab felt alienated from main stream due to denial of their just demands during a long democratic struggle since independence. As it happen all over the word, it led to militant struggle with great loss of lives of military, police and civilian personnel. Killing of Indira Gandhi and massacre of innocent Sikhs in Delhi and other India cities was also associated with this movement.
How to Create Map Views in the Odoo 17 ERPCeline George
The map views are useful for providing a geographical representation of data. They allow users to visualize and analyze the data in a more intuitive manner.
How to Make a Field invisible in Odoo 17Celine George
It is possible to hide or invisible some fields in odoo. Commonly using “invisible” attribute in the field definition to invisible the fields. This slide will show how to make a field invisible in odoo 17.
The Roman Empire A Historical Colossus.pdfkaushalkr1407
The Roman Empire, a vast and enduring power, stands as one of history's most remarkable civilizations, leaving an indelible imprint on the world. It emerged from the Roman Republic, transitioning into an imperial powerhouse under the leadership of Augustus Caesar in 27 BCE. This transformation marked the beginning of an era defined by unprecedented territorial expansion, architectural marvels, and profound cultural influence.
The empire's roots lie in the city of Rome, founded, according to legend, by Romulus in 753 BCE. Over centuries, Rome evolved from a small settlement to a formidable republic, characterized by a complex political system with elected officials and checks on power. However, internal strife, class conflicts, and military ambitions paved the way for the end of the Republic. Julius Caesar’s dictatorship and subsequent assassination in 44 BCE created a power vacuum, leading to a civil war. Octavian, later Augustus, emerged victorious, heralding the Roman Empire’s birth.
Under Augustus, the empire experienced the Pax Romana, a 200-year period of relative peace and stability. Augustus reformed the military, established efficient administrative systems, and initiated grand construction projects. The empire's borders expanded, encompassing territories from Britain to Egypt and from Spain to the Euphrates. Roman legions, renowned for their discipline and engineering prowess, secured and maintained these vast territories, building roads, fortifications, and cities that facilitated control and integration.
The Roman Empire’s society was hierarchical, with a rigid class system. At the top were the patricians, wealthy elites who held significant political power. Below them were the plebeians, free citizens with limited political influence, and the vast numbers of slaves who formed the backbone of the economy. The family unit was central, governed by the paterfamilias, the male head who held absolute authority.
Culturally, the Romans were eclectic, absorbing and adapting elements from the civilizations they encountered, particularly the Greeks. Roman art, literature, and philosophy reflected this synthesis, creating a rich cultural tapestry. Latin, the Roman language, became the lingua franca of the Western world, influencing numerous modern languages.
Roman architecture and engineering achievements were monumental. They perfected the arch, vault, and dome, constructing enduring structures like the Colosseum, Pantheon, and aqueducts. These engineering marvels not only showcased Roman ingenuity but also served practical purposes, from public entertainment to water supply.
Instructions for Submissions thorugh G- Classroom.pptxJheel Barad
This presentation provides a briefing on how to upload submissions and documents in Google Classroom. It was prepared as part of an orientation for new Sainik School in-service teacher trainees. As a training officer, my goal is to ensure that you are comfortable and proficient with this essential tool for managing assignments and fostering student engagement.
Unit 8 - Information and Communication Technology (Paper I).pdfThiyagu K
This slides describes the basic concepts of ICT, basics of Email, Emerging Technology and Digital Initiatives in Education. This presentations aligns with the UGC Paper I syllabus.
The French Revolution, which began in 1789, was a period of radical social and political upheaval in France. It marked the decline of absolute monarchies, the rise of secular and democratic republics, and the eventual rise of Napoleon Bonaparte. This revolutionary period is crucial in understanding the transition from feudalism to modernity in Europe.
For more information, visit-www.vavaclasses.com
5. What is plasma membrane?
Outermost layer (animal)
Thickness is 5-8 nm
Selectively permeable
Serve as outer boundary
Allows some substances to cross more easily than
others
Made of Phospholipids, proteins & conjugated
molecules
Separate and protect cell from external environment
Provide connecting system b/w cell & its environment
Also called cell membrane
5
6. How could you define plasma
membrane?
An outermost envelope surrounding the cell
that separates and protects the cell from the
external environment and provides a
connecting system B/w the cell and its
environment is called plasma membrane.
6
8. Structure of the Plasma
Membrane
The plasma
membrane is
composed of two
layers of
phospholipids
back-to-back.
Phospholipids are lipids with a
phosphate attached to them.
8
9. Phospholipids
Fatty acid tails
hydrophobic
Phosphate group head
hydrophilic
Arranged as a bilayer
Fatty acid
Phosphate
Phospholipids, glycolipids,
cholesterol are amphipathic
lipids containing
hydrophobic and
hydrophillic ends
9
11. Sandwitch model
OR
Danielli- Davson Model
Proposed by Davson and Danielle in 1935
“Cell membrane is lipid bilayer sandwitched
B/w two monomolecular protein layers”
11
12. Fluid mosaic model
In 1972, S.J. Singer & G. Nicolson
proposed Fluid mosaic model.
12
13. What is Fluid mosaic model?
“Cell membrane is lipid bilayer in
which proteins are partially
embeded like Floating iceburgs in
sea”
The fluid mosaic model
describes the plasma membrane as a
flexible boundary of a cell. The
phospholipids move within the
membrane.
13
14. OVERVIEW
Lipid molecules are present in a fluid
state capable of rotating and moving.
The proteins occur as a „mosaic‟ of
discontinuous particles that penetrate
deeply into and even through the lipid
sheet.
Globular proteins are irregularly
embedded in the lipid bilayer.
14
15. Membrane proteins
Membrane proteins are categorized into two
groups:
1- Extrinsic (peripheral) membrane proteins
2- Intrinsic (integral) membrane proteins
15
16. Extrinsic membrane protein
Proteins loosely associated with
membrane surface
Located entirely outside of the lipid
bilayer
Either on the extracellular or
cytoplasmic surface
Also called Peripheral membrane
proteins:
Example:
Cytochrome C of Mitochondria
Cell surface identity marker (antigens)
16
17. Intrinsic membrane proteins
Directly incorporated within the lipid
bilayer
Tightly bound to lipid bilayer
Provides channel for the water-soluble
substances
Also called Integral membrane
proteins
Example:
Transmembrane protein
Transport proteins
Channels, permeases (pumps)
17
18. Membrane is a collage of proteins & other molecules
embedded in the fluid matrix of the lipid bilayer
Extracellular fluid
Cholesterol
Cytoplasm
Glycolipid
Transmembrane
proteins
Filaments of
cytoskeleton
Peripheral
protein
Glycoprotein
Phospholipids
18
19. Proteins domains anchor molecule
Within membrane
nonpolar amino acids
hydrophobic
anchors protein
into membrane
On outer surfaces of
membrane
polar amino acids
hydrophilic
extend into
extracellular fluid &
into cytosol
Polar areas
of protein
Nonpolar areas of protein
19
25. Cytoplasmic side
5. Protein covalently
attaches lipid chain
– fatty acid chain or
prenyl group
(cytoplasmic side)
6. Protein attaches
phosphatidylinositol
via
an oligosaccharide
linker
7, 8. Noncovalent
interaction between
proteins
25
28. Plasma Membrane :
Membrane Proteins
Functional classification
Peripheral Proteins
(only one side of the
membrane)
28
29. Chemical composition
Composed of Lipids, Proteins and
Carbohydrates.
Actual components differs from
tissue to tissue.
Lipids of cell membrane are
Phospholipids
Glycolipids
Sterol
Cholesterol
29
30. Why carbohydrates are not inserted
into the biological membrane?
The carbohydrates are not inserted into
the membrane -- they are too
hydrophilic for that. They are attached
to embedded proteins -- glycoproteins.
30
31. Membrane carbohydrates
Play a key role in cell-cell recognition
ability of a cell to distinguish one cell from
another
Antigens (MHC)
important in organ &
tissue development
basis for rejection of
foreign cells by
immune system
31
32. Four major phospholipids found in mammalian plasma
membrane
There are many „minor‟ phospholipids exists, too.
32
40. Aquaporins
Water moves rapidly into & out of cells
evidence that there were water channels
1991 | 2003
Peter Agre
John Hopkins
Roderick MacKinnon
Rockefeller 40
41. Diffusion
2nd Law of Thermodynamics
governs biological systems
universe tends towards disorder (entropy)
Diffusion
movement fromhighlowconcentration 41
42. Diffusion
Move from HIGH to LOW concentration
“passive transport”
no energy needed
diffusion osmosis
movement of water
42
43. Diffusion through phospholipid bilayer
What molecules can get through directly?
fats & other lipids
inside cell
outside cell
lipid
salt
aa H2Osugar
NH3
What molecules can
NOT get through
directly?
polar molecules
H2O
ions
salts, ammonia
large molecules
starches, proteins
43
44. Channels through cell membrane
Membrane becomes semi-permeable
with protein channels
specific channels allow specific material
across cell membrane
inside cell
outside cell
sugaraaH2O
saltNH3 44
45. The diffusion of water across a selectively
permeable membrane is called osmosis.
Osmosis: Diffusion of Water
Regulating the water flow through the plasma
membrane is an important factor in
maintaining homeostasis within a cell.
45
47. Passive Transport
When a cell uses no energy to move particles
across a membrane passive transport occurs.
Concentration
gradientPlasma
membrane
47
48. Passive Transport by proteins
Passive transport of materials across the
membrane using transport proteins is called
facilitated diffusion.
Plasma
membrane
Channel
proteins
Concentration
gradient
48
49. Facilitated Diffusion
Diffusion through protein channels
channels move specific molecules across
cell membrane
no energy needed
“The Bouncer”
open channel = fast transport
facilitated = with help
high
low
49
50. Passive transport by proteins
The movement is with the concentration
gradient, and requires no energy input from
the cell.
Concentratio
n gradient
Plasma
membrane
Step 1 Step 2
Carrier proteins
50
51. Active Transport
Movement of materials through a membrane
against a concentration gradient is called
active transport and requires energy from the
cell.
Plasma
membrane
Concentration
gradient
Carrier
proteins
Cellular
energy
Step 1 Step 2
51
52. Active Transport
Cells may need to move molecules against
concentration gradient
shape change transports solute from
one side of membrane to other
protein “pump”
“costs” energy = ATP
“The Doorman”
conformational change
ATP
low
high
52
54. Getting through cell membrane
Passive Transport
Simple diffusion
diffusion of nonpolar, hydrophobic molecules
lipids
high low concentration gradient
Facilitated transport
diffusion of polar, hydrophilic molecules
through a protein channel
high low concentration gradient
Active transport
diffusion against concentration gradient
low high
uses a protein pump
requires ATP
ATP
54
56. How about large molecules?
Moving large molecules into & out of cell
through vesicles & vacuoles
Endocytosis ( 2 Types)
1. phagocytosis = “cellular eating”
2. pinocytosis = “cellular drinking”
exocytosis
exocytosis 56
57. ENDOCYTOSIS
- Cell membrane surrounds the substances by
infolding in the form of vacuole or forms a vesicle.
Two Types of Endocytosis
Phagocytosis – engulf solid particles
Pinocytosis – engulf liquid material
57
58. Transport of Large Particles
Endocytosis is a process by which a cell
surrounds and takes in material from its
environment.
Endocytosis Exocytosis
Digestion
Nucleus
Wastes
58
59. Transport of Large Particles
Exocytosis is the expulsion or secretion of
materials from a cell.
Endocytosis Exocytosis
Digestion
Nucleus
Wastes
59
