This document provides an overview of cell membranes and various types of cellular transport. It discusses the structure of the cell membrane and its selectively permeable properties. It describes passive transport mechanisms, including simple diffusion, facilitated diffusion, and osmosis. It also explains active transport, distinguishing between primary active transport which uses ATP hydrolysis, and secondary active transport which utilizes concentration gradients. Vesicular transport processes of exocytosis and endocytosis are also outlined. Examples of abnormalities in transport proteins like sodium-potassium pumps are given. Key references consulted are listed.

1. AKASH CHAUHAN
ROLL NO-2
BATCH-2017-18

2. Cell
membrane
Types of
Cellular
transports
Active
transport
Primary Active
Secondary
Active
Vesicular
transport
Passive
transport

3.  OVERVIEW OF CELL MEMBRANE
 TYPES OF CELLULAR TRANSPORTS
 PASSIVE TRANSPORT
 SIMPLE DIFFUSION
 FACILITATED DIFFUSION
 OSMOSIS
 ACTIVE TRANSPORT
 PRIMARY
 SECONDARY
 VESICULAR TRANSPORT

4. CELL MEMBRANE
1.DOUBLE LAYER OF
PHOSPHOLIPID BILAYER.
PHOSPHATE HEAD
FATTY ACID TAIL
PROTEINS
2.IT CONTAINS
PROTEINS(60-70%)
LIPID(40-50%).
3.CELL MEMBRANE IS-
SELECTIVELY PERMEABLE
IT HAS MEMBRANE PROTEINS
# INTEGRAL PROTEINS
# PUMPS
#CHANNEL PROTIENS
#CARRIER PROTIENS
THESE PROTIENS HELP IN
TRANSPORT ACROSS CELL
MEMBRANE

6.  When a cell uses no energy to move particles
across a membrane passive transport occurs
 Particles go DOWN their concentration
gradient.
 all diffusion & osmosis are passive
transport.

7.  Move from HIGH to LOW
inside cell
outside cell
fat
fat
fat
fat
fat
fat fat
fat
fat
fat
fat
fat
fat
fat
LOW
HIGH

8.  Move from HIGH to LOW through a channel
(has a helper)
inside cell
outside cell
sugar
sugar
sugar
sugar
sugar
sugar
sugar
sugar
sugar
sugar
sugar
sugar
sugar
LOW
HIGH

9.  Osmosis
◦ diffusion of water from HIGH concentration of water
to LOW concentration of water
 across a semi-permeable membrane

10. Movement of materials through a membrane
against a concentration gradient and
requires energy from the cell. IT IS OF TWO
TYPES
 A) PRIMARY
 B)SECONDARY

11.  Primaryactive transport is thetransport ofsustances
uphillusingenergy(ATP hydrolysis)
 It cause a conformational change that results in the
transport ofthemolecule throughthe protein.
 Eg.Na+-K+pump.

12.  The most common: Na/K ATPase pumps reestablish
membrane potential. Present in all cells.
 Two K+ ions are exchanged with 3 Na + ions

13.  The transport of substances against a concentration
gradient involving energy to establish a gradient across
the cell membrane, utilizes the gradient to transport a
molecule of interest up its concentration gradient .
 Eg cotransport (Na/glucose cotransport)
 countertransport

14. 1. Exocytosis [ exo = outside]
movement of large materials OUT of the cell
~a vesicle may fuse with the membrane and
expel its contents
CYTOPLASM
FLUID OUTSIDE CELL

15. 2. Endocytosis [ endo = inside]
movement of large materials to INSIDE of
the cell
~membrane may fold inward, trapping
materials from the outside

16.  ABNORMALTIES IN NA/K PUMP
 CARDIAC FAILURE-↓SED NO. OF Na/K PUMP IN HEART
 HYPERTENSION-↑SED NO. OF Na/K PUMP IN RENAL
TUBULE
 ABNORMALTIES IN ION CHANNEL
 Na CHANNEL - MUSCLE SPASM
 K CHANNEL – CARDIAC FAILURE
 CL CHANNEL-RENAL STONE FORMATION,CYSTIC
FIBROSIS

17. 1. Guyton and Hall Textbook of Medical
Physiology E-Book (Guyton Physiology)
2. Essentials of Medical Physiology by
k.sembulingum
3. Google
4. Slideshare
5. Ganongs Review Of Medical Physiology 25th
Edition