Transcript Microbiology

Microbiology
Part 1
Cell Structure and Function
In this PowerPoint you will
learn the following:
the names of different
cell parts
what function each
part has
(We will use the analogy of a
shopping mall as our example of a
cell.)
cellular organization
and tissue types
A. Common Cell Structures
All cells, regardless of the type, have these
two things:
• an outer covering called a cell membrane
• internal, gelatin-like substance called
cytoplasm
Imagine a water
balloon filled with
hair gel
1. Comparing Cells
The size and shape of the cell relates to its
function.
2. There are two cell types:
•Prokaryotic cells
- lack membranebound, internal
structures or a
nucleus
- are one celled
organisms like
bacteria
•Eukaryotic cells
- have membranebound, internal
structures called
organelles
- are all advanced cells
like protists, fungi, plants
and animals
Prokaryotic and Eukaryotic
Cells
B. Cell Organization
1. Cell Wall – composed of cellulose; grows,
changes shape, and protects the cells of
plants, algae, and most bacteria
**The cell wall’s purpose is to shape
and protect the cell like the outside
wall of a shopping mall, which
provides shape and protection for
it.**
B. Cell Organization
2. Cell Membrane –
protective layer around all
cells.
- found inside the cell wall
of plants, algae, and most
bacteria
- allows food and oxygen
into the cell and waste
products out of the cell
cell
membrane
**The cell membrane controls what
substances come into and out of
the cell like an entrance you have
to pass through to get into and out
of the shopping mall.**
B. Cell Organization
3. Cytoplasm - the watery, gel-like material in
which cell parts move and cell activities
take place
**Cytoplasm is like the
hallways of the mall
where people move.**
B. Cell Organization
A. cytoskeleton – scaffolding-like structure
in cytoplasm which helps keep it in shape
B. In the cytoplasm, eukaryotic cells have
organelles which help with cell life
processes.
Organelles
4. Nucleus
- contains instructions for
everything the cell does;
includes DNA
- regulates and controls
cell activities, acting like
the “brain” of the cell
**The nucleus is like the mall
office, which regulates and
controls activities of the shopping
mall.**
Parts of the Nucleus
• Nuclear Membrane
- protects the
nucleus
- allows substances
to pass in and out of
the nucleus, as the
cell membrane does
for the cell
**The nuclear membrane is like
the main office, the walls of the
mall, and its entrance. It protects
the office (nucleus) and lets
workers in and out.**
Parts of the Nucleus
• Nucleolus
- is the largest structure in
the nucleus of eukaryotic
cells, where it primarily
serves as the site of
ribosome synthesis
- contains chromosomes
which are all piled up in a
tangled jumble (like a
bowl of spaghetti)
- small central location of
chromosomes in nucleus
Parts of the Nucleus
• Chromosomes
- direct the activities
of cells
- are made up of the
DNA instructions for
the cell
**The chromosomes are like a
mall’s office director who
works in the office and directs
all the activities of the
shopping mall.**
Organelles
5.
• Mitochondria
- produces most of the
energy for the cell
- considered the
“powerhouse of the
cell”
- where the energy in
food is stored until it is
released
- help cells do their
work
**Mitochondria are
like the electrical
system of the
shopping mall,
which supplies
electrical energy.**
Organelles
• Chloroplast
- green organelles found
only in plant cells, like the
cell wall
- contains chlorophyll,
which captures energy
from sunlight and uses it
to produce food for the cell
- site of photosynthesis in
plant cells
**Chloroplasts are
like the pizza shop
in the mall that
makes food.**
Organelles
• Lysosomes
- recycling organelles
that work like the
stomach or a trash can
for the cell
- can break down food,
worn out cell parts or
the entire cell (when it’s
time for replacement)
- are organelles that
contain digestive
chemicals
Organelles
• Centrioles
- function during cell
division to separate
daughter cells
- are found in pairs
and move towards
the poles (opposite
ends) of the nucleus
when it is time for cell
division
Manufacturing Organelles
6.
• Ribosomes
- make proteins for cell
activities
- can be free floating or
“bumps along the highway
of the rough ER”
- the site of protein
synthesis
Manufacturing Organelles
•
Endoplasmic Reticulum
- a series of smooth or
rough membranes that
move materials around in
a cell
- works like a highway
throughout the cell
- can be smooth (no
bumps) or rough (bumps
are ribosomes)
Transporting and Storing
Organelles
7.
•
Golgi Bodies
– package and ship
substances out of the cell or
to other parts of the cell. It
doesn’t really matter what the
substance is - their job is
packaging.
- series of flattened
membranes
- are like
for the cell
Transporting and Storing
Organelles
•
Vacuoles
- are also called
vesicles
- store food, water, and
chemicals
- are membrane-bound
spaces for temporary
storage in cells
**Vacuoles are like water tanks and pipes of
the mall which store water.**
C. From Cell to Organism
1. Cell – smallest unit
C. From Cell to Organism
1. Cell – smallest unit
2. Tissue – group of
similar cells working
together on one job.
C. From Cell to Organism
1. Cell – smallest unit
2. Tissue – group of
similar cells working
together on one job.
3. Organ – different types
of tissues working
together make up an
organ.
C. From Cell to Organism
1. Cell – smallest unit
2. Tissue – group of similar
cells working together on
one job
3. Organ – different types of
tissues working together
make up an organ
4. Organ System – group of
organs working together
on a particular function
form a system
C. From Cell to Organism
1. Cell – smallest unit
2. Tissue – group of similar
cells working together on
one job
3. Organ – different types of
tissues working together
make up an organ
4. Organ System – group of
organs working together on
a particular function form a
system
5. Organism – the organ
systems work together to
form the entire organism.
D. General Tissue Types
• Epithelial Tissue
EXAMPLE: Skin
- functions for protection, secretion,
absorption, excretion, filtration, diffusion, and
sensory reception
- form coverings and linings of internal
organs and the body
D. General Tissue Types
• Nerve Tissue
- makes up the brain, nerves, and
spinal cord
- is responsible for coordinating
and controlling many body activities
- stimulates muscle contraction,
creates an awareness of the
environment, and plays a major role in
emotions, memory, and reasoning
- To do all these things, cells in
nervous tissue need to be able to
communicate with each other by way
of electrical nerve impulses.
D. General Tissue Types
• Bone Tissue
- makes up the skeletal
system
- forms a framework and
support system for organs
and the body as a whole
- Bone marrow is also
responsible for production of
red blood cells.
D. General Tissue Types
• Blood- is a special transport fluid
Has four parts:
1. Red cells deliver nutrients and
oxygen to the body cells and
transport waste products away
from those same cells.
2. White cells fight off infections
and germs.
3. Platelets function during blood
clotting.
4. Plasma is the liquid portion of
the blood that helps it flow.
D. General Tissue Types
• Muscle Tissue
- is composed of cells that have
the special ability to shorten or
contract in order to produce
movement of the body parts
There are three types:
1. Skeletal muscles- attached to
bones for voluntary movement
2. Smooth muscles- line internal
organs; involuntary movement
3. Cardiac muscles- heart muscle;
branching cells that NEVER get
tired