Microorganisms
A living creature too small to see with
the naked eye.
Scientific Classification System
Did King Phillip Come Over For Good Spaghetti?
• Domain - (3)
• Kingdom – (5 to 8)
• Phylum (over 40 for Animals alone)
• Class
• Order
• Family
• Genus
• Species
3 Domains
5 kingdom example
Another 8 kingdom classification
• The 6 Kingdom classification system is
currently pretty universally accepted and the
one we are going to use and focus on.
• cell's origin - 18 min
Why Protists?
• Humans could not live on Earth if it were not for
protists. Why?
• Plant-like protists produce almost one-half (50%) of
the oxygen on the planet through photosynthesis!
• Other protists decompose and recycle nutrients that
humans need to live.
• All protists make up a huge part of the food chain.
Humans use protists for MANY reasons:
• Many protists are also commonly used in medical research.
For example, medicines made from protists are used in
treatment of high blood pressure, digestion problems,
ulcers, and arthritis.
• Other protists are used in scientific studies. For example,
slimemolds (including D. discoideum, a soil-living protist)
are used to analyze the chemical signals in cells.
• Protists are also valuable in industry (food production).
Look on the back of a milk carton. You will most likely
see carrageenan, which is extracted from red algae. This is
used to make puddings and ice cream solid (Figure below).
Chemicals from other kinds of algae are used to produce
many kinds of plastics.
Summary

Protists make up a huge part of the food chain and supply much of the oxygen we
breathe.

Protists are used in medicine and as food additives.
From Algae to Fuels
• https://www.youtube.com/watch?v=IxyvVke
W7Nk
Paramecium
Organelles
• Organelles – structures in a cell that perform a
special function.
• Examples – contractile vacuole, food vacuole,
nucleus, mitochondria.
Paramecia “parts”
1. Cilia - hair like appendages (moves food into the
oral groove and helps the entire cell move.)
2. Pellicle - a membrane covering that protects the
paramecium (like skin)
3. Macronucleus - larger nucleus which performs
normal cell functions.
Paramecia “parts”
4. Micronucleus - smaller nucleus which is
responsible for cell division.
5. Contractile Vacuole - contracts and forces extra
water out of the cell
Radiating Canals – paths to the contractile
vacuole.
6. Oral Groove (mouth pore)- collects and directs
food into the gullet.
Paramecium “parts” continued
7. Gullet – Helps form food vacuoles and
directs the food into them.
8. Food Vacuole - storage pocket for
food and digestive juices.
9. Anal Pore – excretes wastes.
Paramecium “parts” continued
10. Trichocyst - used for defense, shoots threads out
of cells!
Cytoplasm - intercellular fluid needed to contain vital
cell parts.
11. Endoplasm (more interior dense liquid inside of
cell)
12. Ectoplasm (more exterior clear liquid inside of
the cell)
Paramecium Traits
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Move by cilia
Single- celled
Unique oral grove
Heterotroph (must eat their energy)
Amoeba
Amoeba
Euglena
Euglena
Food storage
of starch
Protists
• Protists
– Organisms that belong to the kingdom protista.
– They are NOT plants, animals, bacteria, or fungi.
– A very diverse group of organisms.
– Basically organisms that don't fit into the other
groups.
- Eukaryotic organisms (they have a nucleus)
- They do NOT have specialized tissues.
Types of Protista
One way protists can be divided up is according to how they move.
• Cilia - Some protists use microscopic hair called cilia to move.
These tiny hairs can flap together to help the organism move
through water or other liquid. (Paramecium is an example)
• Flagella - Other protists have a long tail called flagella. This tail
can move back and forth helping to propel the organism.
(Euglena is an example)
• Pseudopodia - This is when the protist extends part of its cell
body to scoot or ooze along. (Amoebas are an example)
How do they eat?
Different protists gather energy in different ways.
Some are autotrophs (make their own food), some
are heterotrophs (must eat food).
– Some eat food and digest it internally.
– Others digest their food outside of their bodies by
secreting enzymes. Then they eat the pre-digested
food.
– Still other protists use photosynthesis like plants. They
absorb sunlight and use this energy to make glucose.
Algae - autotroph
• One major type of protista is algae.
• Algae are protists that perform photosynthesis.
• Algae are very similar to plants. They have chlorophyll
and produce food using oxygen and the energy from
the Sun. (However, they are not considered plants because they do have specialized organs
or tissues. )
• Algae are often divided up by their color such as red,
brown, and green.
Slime Molds – another Protist
•
Slime molds are different from the type of molds that are fungi. There are
two types of slime molds: cellular and plasmodial.
• Plasmodial slime molds are made from one large cell.
• They are also called acellular. Even though these organisms are just one
cell, they can be very large, even up to several feet wide! They also can
have many nuclei in their single cell.
• Cellular slime molds are small single-celled protists that can join together
to work as a single organism. Different cellular slime molds will take on
different functions when they work together.
Amoebas
•
Amoebas are small single-celled organisms that
move using pseudopods.
• Amoebas are shapeless and eat by engulfing their
food with their bodies.
• Amoebas reproduce by splitting in two through
the cell division process called mitosis.
Interesting Facts about Protists
•
Many protists act as pathogens to humans. This means they
cause diseases.
• The disease malaria is caused by the protist Plasmodium
falciparum.
• If an amoeba is cut in half, the half with the nucleus will
survive, while the other half will die.
• The word "pseudopod" comes from Greek words meaning
"false feet.“
• Seaweed is a type of algae that grows in the ocean.
• Virtual drops of pond water
• http://www.microscopyu.com/moviegallery/p
ondscum/
• all about the paramecium including video of
eating red yeast
Units
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•
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Kilo- thousands
Hecto – hundreds
Deca – tens Base (if meter is your base, m)
Deci – one-tenth
Centi – one-hundredth (cm)
Milli – one-thousandth (mm)
Micro – one-millionth (um)
• paramecium quizlet flashcards
• Mrs. McArthur's paramecium quizlet
flashcards