Download Low

CELLULAR LEVEL OF
ORGANIZATION
Roselyn Aperocho – Naranjo
Pharmacy Instructor
USPF – College of Pharmacy
www.roselynnaranjo.vze.com
THE ANIMAL CELL
THE PLASMA MEMBRANE
• outer surface separating the cell’s
environment from the external
environment outside the cell
• selective barrier that regulates the
flow of materials into and out of the
cell
• helps maintain the appropriate
environment for normal cellular activities
• play a role in communication both
among cells and between cells and
their external environment
THE ANIMAL CELL
CYTOPLASM
•Contains cellular components
between plasma membrane and
nucleus
• consist of two components:
Cytosol – fluid portion
-
contains water
and dissolved
solutes and
suspended paticles
- sorrounded by
organelles susch as
ribosomes, etc.
THE ANIMAL CELL
NUCLEUS
forms the package for our genes and
their controlling factors.
•Store genes on chromosomes
•Organize genes into chromosomes
to allow cell division.
•Transport regulatory factors & gene
products via nuclear pores
Produce messages ( messenger
Ribonucleic acid or mRNA) that code
for proteins
THE ANIMAL CELL
NUCLEUS
4 Parts
Nuclear Membrane
•Nucleoplasm or Karyolymph
•Nucleolus
•Chromatin Network
THE ANIMAL CELL
ROUGH ENDOPLASMIC RETICULUM
• a network of tubules, vesicles and sacs
that are interconnected.
•serve specialized functions in the cell
including protein synthesis, sequestration
of calcium, production of steroids,
storage and production of glycogen, and
insertion of membrane proteins.
•bears the ribosomes during protein
synthesis.
THE ANIMAL CELL
LYSOSOMES
• the cells' garbage disposal
system.
• are used for the digestion of
macromolecules
• digest excess or worn-out organelles,
food particles, and engulfed viruses or
bacteria.
THE ANIMAL CELL
MICROTUBULES
• also known as Centrioles
•Long and straight cylinders
•Responsible for the movement during
cell division
•Contains cilia and flagella
THE ANIMAL CELL
SMOOTH ENDOPLASMIC RETICULUM
• It also provides a large surface
area for the organization of
chemical reactions and synthesis
•serves as a storage of calcium
•transport chemicals
between and within cells.
THE ANIMAL CELL
SMOOTH ENDOPLASMIC RETICULUM
•packages proteins for transport,
synthesizes membrane
phosolipids, and releases calcium
•transformation of bile pigments,
glycogenolysis (the breakdown of
glycogen), and detoxification of
many drugs and chemical agents
THE ANIMAL CELL
GOLGI BODIES
• essential in modifying, sorting, and
packaging these substances for cell
secretion (exocytosis) or for use
within the cell.
• It primarily modifies proteins
delivered from the rough
endoplasmic reticulum but is also
involved in the transport of lipids
around the cell, and the creation of
lysosomes
THE ANIMAL CELL
GOLGI BODIES
• it can be thought of as similar to a
post office; it packages and labels
items and then sends them to different
parts of the cell.
• converts chemical energy of food
such as sugars to the chemical energy
of a molecule called ATP
THE ANIMAL CELL
MITOCHONDRIA
• is an organelle that carry out
cellular respiration of the cell.
• converts chemical energy of food
such as sugars to the chemical energy
of a molecule called ATP
THE PLASMA MEMBRANE
LIPID BILAYER


Basic structural framework
Consist of two back to back
layers made up of three
types of lipid molecules
– (75%) Phospholipids,
cholesterol, glycolipids
2 layers of phospholipids
• Phosphate head is
polar (water loving)
• Fatty acid tails nonpolar (water
fearing)
• Proteins embedded
in membrane
Functions
Controls what enters and exits the cell to
maintain an internal balance called
homeostasis
b. Provides protection and support for the cell
have pores (holes) in it
c. Selectively permeable: Allows some molecules
in and keeps other molecules out
d. The structure helps it be selective!
a.
Structure of the Cell Membrane
Outside of cell
Proteins
Proteins
Transport
Protein
Carbohydrate
chains
Phospholipids
Inside of cell (cytoplasm)
Types of Cellular Transport

Passive Transport
cell doesn’t use energy
1.
2.
3.

Diffusion
Facilitated Diffusion
Osmosis
Weeee!!!
high
low
Active Transport
cell does use energy
1.
2.
3.
Protein Pumps
Endocytosis
Exocytosis
This is
gonna be
hard work!!
high
low
Passive Transport (HighLow)



cell uses no energy
molecules move randomly
Molecules spread out from an area of high concentration
to an area of low concentration.
Four types:
1.
Diffusion
2.
Facilitative Diffusion – diffusion with the help of transport
proteins
3.
Osmosis – diffusion of water
4.
Filtration -
Passive Transport (HighLow)
1.
Diffusion: random movement
of particles from an area of
high concentration to an
area of low concentration.
(High to Low)
•
Diffusion continues until all
molecules are evenly spaced
(equilibrium is reached)-Note:
molecules will still move around but
stay spread out.
Passive Transport (HighLow)
2. Facilitated diffusion:
diffusion of specific particles
through transport
proteins found in the
membrane
a. Transport Proteins are
specific – they “select”
only certain molecules to
cross the membrane
b. Transports larger or
charged molecules
Facilitated
diffusion
(Channel
Protein)
Diffusion
(Lipid
Bilayer)
Carrier Protein
Passive Transport (HighLow)
Glucose
molecules
2. Facilitated diffusion:
High Concentration
High
Cell Membrane
Low Concentration
Through a 
Transport Protein
Low
Passive Transport (HighLow)
3.Osmosis: diffusion of water through a selectively
permeable membrane
 Water moves from high to low concentrations
•Water moves freely through
pores.
•Solute (green) to large to
move across.
Passive Transport (HighLow)
Filtration
Active Transport (Low  High)





cell uses energy
actively moves molecules to where they are needed
Movement from an area of low concentration to
an area of high concentration
(Low  High)
Three Types:
–
–
–
Protein pumps
Endocytosis
Exocytosis
Active Transport (Low  High)
1. Protein Pumps transport proteins
that require energy
to do work
–
Example: Sodium /
Potassium Pumps
are important in
nerve responses.
Protein changes shape
to move molecules: this
requires energy!
Active Transport (Low  High)
2. Endocytosis: taking bulky material into a cell
•
•
•
•
•
Uses energy
Cell membrane in-folds around food particle
“cell eating”
forms food vacuole & digests food
This is how white blood cells eat bacteria!
Active Transport (Low  High)
3. Exocytosis: Forces
material out of cell in bulk
•
membrane surrounding the
material fuses with cell
membrane
•
Cell changes shape –
requires energy
EX: Hormones or wastes
released from cell
•
Hypotonic Solution
Hypotonic: The solution has a lower concentration of
solutes and a higher concentration of water than inside
the cell. (Low solute; High water)
Result: Water moves from the solution to inside the cell): Cell Swells
and bursts open (cytolysis)!
Hypotonic Solution
Hypertonic: The solution has a higher concentration of solutes and a
lower concentration of water than inside the cell. (High solute; Low
water)
shrinks
Result: Water moves from inside the cell into the solution: Cell
shrinks (Plasmolysis)!

Osmosis Animations for
isotonic, hypertonic,
and hypotonic solutions
Isotonic Solution
Isotonic: The concentration of solutes in the solution is equal to the
concentration of solutes inside the cell.
Result: Water moves equally in both directions and the cell remains
same size! (Dynamic Equilibrium)
What type of solution are these cells in?
A
B
Hypertonic
C
Isotonic
Hypotonic
How Organisms Deal with Osmotic
Pressure
•Bacteria and plants have cell walls that prevent them from overexpanding. In plants the pressure exerted on the cell wall is called
tugor pressure.
•A protist like paramecium has contractile vacuoles that collect
water flowing in and pump it out to prevent them from overexpanding.
•Salt water fish pump salt out of their specialized gills so they do
not dehydrate.
•Animal cells are bathed in blood. Kidneys keep the blood isotonic
by remove excess salt and water.
Prepare one – half sheet of paper
Good Luck