Transcript 11.1 protists

Warm up
 How many different types of cells do you recognize in
the following figure?
Introduction
 Some are tiny that they cannot be seen
without a microscope. Others grow many
meters long. Some are poisonous. And
some provide food for people. What are
they??
Objectives
 Describe the characteristics of protists.
 Describe four ways that protists get food.
 Explain the meaning of heterotrophs.
 Define decomposers
 Explain how protists can be parasites.
Characteristics of protists
 Protist: a protist is a member of the kingdom protista.
Protists differ from other living things in many ways.
 The following figure shows different types of protists:
Characteristics of protists
 They are very diverse and have few traits in common.
 Can be single-celled, many cells or live in colonies.
 Some protists produce their own food, some eat other organisms
or decaying matter
 Some protists can control their own movement and other can’t.
 All protists are eukaryotic and have nucleus.
 Protists are less complex than other eukaryotic organisms
 Unlike fungi, plants or animals, protists have no specialized
tissues
Protists and food
Protists get food in many ways.
Some protists can make their own
food. Other protists eat other
organisms, parts or products of
other organisms, or the remains of
other organisms. Some protist use
more than one method of getting
food.
Producing food, finding food
 What are producers?
 Some protists act like green plant and produce their own
food through photosynthesis since they contain chloroplasts.
 What are heterotrophs?
 Heterotrophs are organisms that can’t make their own food,
they rather get food from their environment.
 These organisms eat other organisms, parts or products of
other organisms, or the remains of other organisms
Decomposers
 Some protists are decomposers since they
feed on the remains of other organisms or
they get energy by breaking down organic
matter.
 Some protists get energy in more than one
way. Ex: slime molds, get energy by
engulfing both small organisms and
particles of organic matter.
Parasites
 Some protists are parasites.
 A parasite invades another organism
to get the nutrients that it needs and
cause harm.
 An organism that a parasite invades is
called a host.
 Parasitic protists invade fungi, plants
or animals.
Kinds of protists
 Objectives:
1- describe how protists can be organized into three groups
based on their shared traits.
2- List an example for each group of protists.
Kinds of protists
 One way that protists are grouped is based on shared
traits.
 Scientists can place protists into three groups:
1- producers
2- heterotrophs that can move
3- heterotrophs that can’t move
Protist producer
 Many protists are producers like plant. How?????
 These protist producers are called Algae
 All algae have the green pigment chlorophyll, which is
used in making food.
 Most algae also have other pigments that give them color.
 Almost all algae live in water
 Algae can be single-celled or many celled
 Some of these algae can grow to many meters in length
Protist producer
 Free-floating single-celled algae are called
phytoplankton.
 They can’t be seen without a microscope.
 They usually float near the water’s surface.
 They provide food for most other organisms in the
water.
 They also produce much of the world’s oxygen.
Euglenoids or euglena
 Euglenoids are producers protists they make their own
food since they have chlorophyll.
 They live in fresh water.
 They do have flagella which helps them moving
Heterotrophic protists
Heterotrophic protists cannot make
their own food. They are consumers,
decomposers, or parasites. Those
that can move are sometimes called
protozoans. Like Amoeba.
Amoeba
 Amoebas are soft, jelly like protozoans.
 They are found in both fresh and salt water, in soil and
as parasites in animals.
 They are mobile heterotrophs since they have
pseudopods.
Wrap up
 What are protists?
 What are the three types of protists?
 What are phytoplanktons?
 What are protozoans?