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Instructor
Prof. Park Se Won
&
Dr. Chandrama P. Upadhyaya
• 209, Life Sciences Building
• 02-450-3739, 010-3470-8050,
• [email protected],
[email protected]
Teaching Assistant
•
•
•
•
Mrs. Moon Soo Yeon
209 Life Sciences Building
02-450-3739, 02-3436-5439
[email protected]
The Book
LEWIN’S
CELLS
SECOND EDITION
Lynne Cassimeris
V.R. Lingappa
G. Plopper
Copyright © Jones and Bartlett publishers.
Evaluation
• Two examinations counting 35% each.
•
- Mid term Exam (date to be announce)
•
- Final Exam (date to be announce)
• Attendance 20%
• Home work 10%
Course Content
Chapter 1: Introduction
1. What is cell? 2. Structure of cell organelles and function, 3. Eukaryotes and
prokaryotes, DNA and RNA the cellular hereditary material of the cell, 4.
Mitochondrial and chloroplast specialized system 5. Organization and structure of
cells 6. Viruses are supramolecular assemblies acting as cell parasites
Chapter 2: Membrane and Transport mechanism
Basic structure of plasma membrane, 2. Channels, 3. Carriers, 4. Electrochemical gradient, 5.
Active and passive transport mechanism, 6. Selective water transport through aquaporin
channels,, 7. H+ATPase pump.
Chapter 3: Nuclear structure and transport
1.Nucleus basic function and structure, Nuclear pore complexes, Nuclear
structural variance according to the cell type, Export of proteins and other
molecules from nucleus, Multiple class of RNA exported from nucleus
Chapter 4: Chromatin and Chromosome
1.Basic structural and functional concept, 2. Euchromatin & hetrochromatin, 3. Centromere, 4.
Telomere, 5. lampbrush Chromosomes, 6. Nucleosome concept and function, 7. Path of nucleosome
and chromatin fiber, 8. Histones and chromatin interaction, 9. Chromosome condensation
Chapter 5: Cell Division and Cell Cycle regulation
Concepts of Mitosis, Actual mechanism and Mitosis machinary, Regulatin of Mitosis, Meiosis
Concept and Mechanism, Regulation of Meosis, Events of Cell cycle, Cycele of Cyclin dependent
kinase activities, Regulation of cell cycle and its detailed mechanism
Chapter 6: Apoptosis and Cancer
Concepts and facts of apoptosis, Role of Caspases, Inhibitor of apoptosis, Apoptosis signaling in cell
and regulation, Apoptosis feature of insects, Apoptosis and disease, Cancer cell and characteristics,
mechanism of cancerous cell formation, Regulation of cancel in living system, Impact of mutation and
DNA repair on cancel, control measurement of cancer cell in animals.
Chapter 7: Principle of Cell Signaling
Introduction to cellular signaling, receptors, catalyst and amplifier, cellular signaling and
modifier proteins, Second messengers, Ca+2 signaling, Lipid and lipid derivative
signaling molecules, Signaling through ion channels, G protein signaling
Chapter 8: The cytoskeleton: Microtubules and actin
General function of microtubules, Structures of tubules, Microtubule assembly and
disassembly, Microtubules dynamics, Microtubules based motor protein, The actin
structure and function, Interaction between microtubules and actin, Actin filaments and
structurally polarized polymers, Control of cellular actin polymerization, Myosin
structures and function, regulation of myosin
Chapter 9: Prokaryotic cell Biology
Introduction to prokaryotic lifestyle, Cell structures, Gram negative and positive
bacterial development, Bacterial nucleoid and cytoplasm, bacterial chrosome, Flagella
development and structures, prokaryotic response to environmental stress, The
symbiosis with eukaryotes, Biofilm development
Chapter 10: Plant Cell Biology
Introduction, The growth of plant cell, tissue organization of plant, Plant mitosis without
centrosome, The cell plate, Plasmodesmata and plant intercellular channels, Cell expansion
and role of vacuole, Cellulose and cell wall assembly, Differentiation of xylem and phloem,
Plastids and its structure with function
Chapter 11: DNA Replication, Mutation & DNA repair
Types of DNA replication, DNA polymerase, Origins of replication, The replication fork,
Regulation of replication, Termination of replication
Chapter 12: Transcription, Translation and post-translational modifications
Major steps in Transcription, Reverse transcription, Central Dogma, Translation, Genetic
code, mRNA processing, RNA splicing
Chapter 1
INTRODUCTION TO CELL BIOLOGY
 We are in the midst of a "Golden Era" of biology.
 The revolution is mostly about treating biology as an information
science, not only specific biochemical technologies.
What is cell?
The cell is the functional basic unit of life.
It was discovered by Robert Hooke and is the functional unit of all
known living organism.
It is the smallest unit of life that is classified as a living thing, and is often
called the building block of life.
What is cell Biology?
Cell biology (also called cellular biology or formerly cytology, from the Greek
kytos, "container") is an academic discipline that studies cells.
This includes their physiological properties, their structure, the organelles
they contain, interactions with their environment, their life cycle, division and
death. This is done both on a microscopic and molecular level.
Cell Theory
All organisms are composed of one or more cells.
Cells are the smallest living units of all living organisms.
Cells arise only by division of a previously existing cell.
Cell Characteristics
Genetic material
single circular molecule of DNA in prokaryotes
double helix located in nucleus in eukaryotes – nuclear envelope (double
membrane
Cytoplasm fills cell interior –
sugars, amino acids, proteins - organelles
Plasma membrane encloses the cell – phospholipid bilayer
GENERALIZED EUKARYOTIC CELL
Animal Cell
CELL SIZE
Most cells are relatively small because as
size increases, volume increases much more
rapidly.
longer diffusion time
Visualizing Cells
Resolution - minimum distance two points can be apart and
still be distinguished as two separate points.
Compound microscopes - magnify in stages using multiple lenses
Transmission electron microscope - electrons transmitted through
specimen
Scanning electron microscope - electrons beamed onto surface of
the specimen
PROKARYOTIC CELLS
Simplest organisms
Cytoplasm is surrounded by plasma membrane and
encased in a rigid cell wall composed of
peptidoglycan.
no distinct interior compartments
gram-positive – thick single layer wall that
retains a violet dye from Gram stain procedure
gram-negative – multilayered wall does not
retain dye
Susceptibility of bacteria to antibiotics depends
on cell wall structure.
PROKARYOTIC CELLS
Some use flagellum for locomotion
threadlike structures protruding from cell surface
Rotary
motor
Some use flagellum for locomotion
threadlike structures protruding from cell surface
EUKARYOTIC CELLS
Characterized by compartmentalization
by an endomembrane system, and the
presence of membrane-bound organelles.
Central vacuole – plants, storage
Vesicles (smaller)
Chromosomes - DNA and protein
Cytoskeleton (internal protein scaffolding)
Cell walls – plants and fungi
CELL MEMBRANE
-Boundary of the cell
-Made of a phospholipid bilayer
NUCLEUS
•Repository for genetic material and directs activities of the cell.
•Usually single, some cells several, RBC none
-Nucleolus - region of intensive ribosomal RNA synthesis
•Surface of nucleus bound by two phospholipid bilayer
membranes
-Nuclear membrane
-Nuclear pores – protein gatekeepers
•Usually proteins going in and RNA going
out
CHROMOSOMES
•DNA of eukaryotes is divided into linear
chromosomes.
-exist as strands of chromatin, except during
cell division.
-associated with packaging histones,
packaging proteins
-nucleosomes
ENDOPLASMIC RETICULUM
•Largest internal membrane, Composed of Lipid bilayer.
•Serves as system of channels from the nucleus.
•Functions in storage and secretion.
•Rough ER is “rough” because of associated ribosomes (sites of
protein synthesis
•Smooth ER - lack associated ribosomes – contained
embedded enzymes, catalyze synthesis of carbohydrate and
lipid molecules
Golgi apparatus
•collection of Golgi bodies
-collect, package, and distribute molecules synthesized
at one location in the cell and utilized at another
location
-Front - cis , Back – trans
-Cisternae – stacked membrane folds
Vesicles
•Lysosomes - membrane-bound vesicles
containing digestive enzymes – from Golgi
•Microbodies - enzyme-bearing, membraneenclosed vesicles.
-Peroxisomes - contain enzymes that catalyze the
removal of electrons and associated hydrogen atoms
-Peroxisome – named for hydrogen peroxide produced
as a by-product
Enzyme breaks down to water and oxygen
Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display.
Cytoplasm
Endoplasmic
reticulum
Phagocytosis
Food
vesicle
Golgi
apparatus
Lysosomes
Plasma
membrane
Extracellular
fluid
Digestion of
phagocytized
food particles
or cells
Transport
vesicle
Old or damaged
organelle
Breakdown
of old
organelle
RIBOSOMES
•Ribosomes are RNA-protein complexes
composed of two subunits that join and attach
to messenger RNA.
-site of protein synthesis
assembled in nucleoli
MITOCHONDRIA
-“Powerhouse of the cell”
-Cellular respiration occurs
here to release energy for
the cell to use.
-Bound by a double
membrane
-Has its own strand of DNA
CHLOROPLAST
-Found only in plant
cells.
-Contains the green
pigment chlorophyll.
-Site of food (glucose)
production.
-Bound by a double
membrane.
CYTOSKELETON
•Network of protein fibers supporting cell shape and
anchoring organelles
-Actin filaments
Microtubules
•cell movement
-Microtubules
Intermediate
filaments
•Hollow tubes
•Facilitate cell movement
•Centrioles – barrel shaped
•organelles occur in pairs –
help assemble animal cell’s microtubules
Actin
-Intermediate filaments
•Stable - don’t break down
CYTOSKELETON
PLANT CELLS
Central vacuole
often found in the center of a plant, and serves as a storage facility for water
and other materials
Cell wall
primary walls – laid down while cell is growing
middle lamella – glues cells together
secondary walls – inside the primary cell walls after growth
ANIMAL CELLS
Animal cells lack cell walls.
-form extracellular matrix
provides support, strength, and resilience