Introduction to biochemistry CELL Cell and its biochemical aspects Cell membrane structures Membrane proteins

1. D P T - F A 1 2 - 0 3 6
D O C T O R O F P H Y S I C A L T H E R A P Y
T H E U N I V E R S I T Y O F F A I S A L A B A D
By
Nabeel Amjad

2. Topics
Introduction to biochemistry
CELL
 Cell and its biochemical aspects
 Cell membrane structures
 Membrane proteins

3. Introduction to Biochemistry
Introduction
 Biochemistry, sometimes called biological chemistry, is
the study of chemical processes within, and relating
to, living organisms
 Much of biochemistry deals with the structures, functions and
interactions of biological macromolecules, such
as proteins, nucleic
acids, carbohydrates and lipids, which provide the
structure of cells and perform many of the functions
associated with life.
 The chemistry of the cell also depends on the reactions of
smaller molecules (Micro molecules) and ions. These can
be inorganic, for example water and
metal ions, or organic, for example the amino acids which
are used to synthesize proteins

4. Continued.
Areas of application
biochemistry are applied primarily in
 medicine,
 nutrients,
 agriculture.
1. in medicine, biochemist, investigate the causes and
cures of disease.
2. in nutrients, they study how to maintain health and
study the effects of nutritional deficiencies.
3. In agriculture, biochemists investigate soil and
fertilizers, and try to discover ways to improve crop
cultivation, crop storage and pest control.

5. Cell
 Definition:
Cells are the structural and functional units of all
living organisms.
 Types
cells are two types
1. Prokaryotic cell: that lake membrane bounded
structures
2. Eukaryotic cell: true cell

6. Eukaryotic cell

7. Cell Structures
 The Plasma Membrane—A Cell's Protective Coat
 The Cytoskeleton—A Cell's Scaffold
 The Cytoplasm—A Cell's Inner Space
 Genetic Material
Cell Organelles include
 The Nucleus—A Cell's Center
 The Ribosome—The Protein Production Machine
 Mitochondria and Chloroplasts—The Power
Generators
 The Endoplasmic Reticulum and the Golgi Apparatus
 Macromolecule Managers
 Lysosomes and Peroxisomes—The Cellular Digestive
System

8. Cell Membrane
• The cell membrane, or plasma
membrane, is a biological
membrane that separates the interior
of cell from its external environment
• Regulates what comes in and out of
the cell
• Main components: proteins and
phospholipids
• The cell membrane is selectively
permeable

9. Cell Membrane Structure
 Cell membrane is mainly composed of
1. Lipid bilayer
2. Proteins
 According to fluid mosaic model cell membrane
consists of lipid bilayer with embedded proteins

10. Lipid bilayer
 universal component of all cell
membranes
 two layers of fat cells organized in
two sheets
 most abundant class of lipid
molecule found in cell membranes is
the phospholipids
 Phospholipids molecule contain
 phosphate group (polar head)
 two fatty acid chain group (nonpolar tail).

11. Phospholipids arrange themselves to expose
hydrophilic head and hide hydrophobic tail

12. Cell membrane proteins
 There are mainly two types of cell membrane
protein
 Integral proteins
 Peripheral proteins

13. Integral proteins
 permanently attached to the membrane
 can perform functions both inside and outside of the
cell.
 Further two types
 Integral polytopic proteins, also known as "transmembrane
proteins,“
 Integral monotopic proteins that are attached to only one side
of the membrane and do not span the whole way across

14. Peripheral membrane proteins
 temporarily attached either to the lipid bilayer or to
integral proteins
 dissociate by treatment with a polar reagent, such as
a solution with an elevated pH or high salt
concentrations.
 Dissociate without harming lipid bilayer