Review for Test: Protists, Prokaryotes, and Viruses

1
Review for Test Protists, Prokaryotes, and
Viruses

• ESI
• Spring 2006

2
Protists The Basics

• Eukaryotic w/ nucleus!
• Algae, Euglenozoa, Protozoa
• Classified by movement
• Flagellate
• Ciliate
• Sarcodina
• Sporozoa

What organism is this?
3
Prokaryotes The Basics

• Appeared 3.8 billion years ago, no nuclei!
• Archaea are oldest live in extreme conditions
  (no O2, boiling, freezing)
• Cyanobacteria are photosynthetic
• Eubacteria can be parasites, decomposers, or
  helpful to plants and animals!

4
Viruses The Basics

• Not alive! Need a host to reproduce
• Structure is simple
• Protein capsid
• Genetic material
• Resistant to antibiotics
• Affect all organisms
• Humans protect with interferons

HIV
5
Question 1

• How are Eukaryotes different from Prokaryotes?
• Eukaryotes have a nucleus, Prokayotes do not have
  a nucleus. Instead, their genetic material is
  exposed within their cytoplasm.

6
Prokaryotic Cell Structure
7
Eukaryotic Cell Structure
8
Question 2

• Why are viruses not considered living things?
• One of the criteria for living creatures is the
  ability to reproduce. Viruses are unable to
  reproduce without hijacking and destroying a
  host cell. Also, viruses dont grow, develop, use
  energy, or respond to their environments.

9
Viral Reproduction
http//www.lewiston.k12.id.us
10
Question 3

• Why are protozoa called animal-like protists?
  Why are algae called plant-like protists?
• Protozoa are not photosynthetic. Instead, they
  have parts that allow them to move and collect
  food in a way that is animal-like. Algae
  contain chlorophyll and are therefore capable of
  making their own food.

11
Algae vs. Protists
12
Question 4

• Why are we unable to classify euglenozoa as
  either protozoa or algae?
• They are a mix of both! They contain chlorophyll
  (like algae and plants), yet they can move around
  in different ways (like protozoa and animals). In
  a way, they are hybrids!

13
Euglenozoa
14
Question 5

• What are the three basic shapes of Prokaryotes?
• Cocci, Bacilli, and Spirilla

15
Three Basic Shapes
Spirilla
Cocci
Bacilli
16
Question 6

• What are the four modes of movement of Protists
  (Protozoa)?
• Flagellate have flagella, Cilliate have
  cilia, Sarcodina - pseudopodia, and Sporozoa no
  movement

17
Four Modes of Movement
18
Question 7

• What is an interferon?
• Interferons are proteins that are made by our
  bodies as an early defense against viruses. As
  one cell is infected by a virus, it secretes this
  substance to help make nearby cells more
  resistant.

19
Question 8

• Why is HIV a particularly deadly disease?
• HIV infects the cells of the immune system that
  are necessary for battling the pathogen (an agent
  that causes disease). Now, other infections can
  harm this person!

20
Question 9

• What is an endospore?
• An endospore is a protective covering that
  prokaryotes produce when their environment gets
  too dry. When the going gets tough, the tough get
  endospores!

21
Endospore
22
Question 10

• What matter was used in your Petri dish to
  provide nutrients for Eubacteria? Where does this
  substance come from?
• Agar! Agar comes from seaweed and is used to grow
  bacteria and fungi.