DIVERSITY NOTES
Levels of Organization:
Cells – Tissue – Organ – Organ System - Organism – Population – Community – Ecosystem
CLASSIFICATION - CH 19 - PAGES 308-314
I. TAXONOMY - Study of the grouping of organisms
A. Taxon- group of organisms defined by the classification scheme (class, family)
B. Levels of Taxa – Domain, Kingdom, Phylum (in animals)/Division (in plants), Class, Order,
Family, Genus, Species
C. Three Domains, Six Kingdoms – Listed from most primitive to most advanced
1. Domain Archaea – Kingdom Archaebacteria
2. Domain Bacteria – Kingdom Eubacteria
3. Domain Eukarya
a. Kingdom Protista - euglena, amoeba, paramecium, algae
b. Kingdom Fungi
c. Kingdom Plantae - ferns, gymnosperms, angiosperms
d. Kingom Animalia - vertebrates, invertebrates
II. BINOMIAL NOMENCLATURE - The naming of an organism
A. The scientific name of an organism is: Genus/species
1. Homo sapiens – humans 2. Felis domesticus - house cat
B. Rules
1. Capitalize 1st letter of genus name
2. Underline genus and species names
3. 1st use of name must be written out in each paragraph
4. After 1st use - abbreviate genus name to 1st letter: H. sapiens F. domesticus
THERMOREGULATION – Strategies for regulation of body temperature & metabolism
I. Ectothermy – when organisms use external thermal energy to help regulate & maintain body temperature
A. Behavioral, physiological, or anatomical adaptations that increase an animal's ability to survive
in a certain environment
1. hibernation 2. hair, feathers, blubber
3. staying in the shade 4. restrict activity to night
II. Endothermy – when organisms use thermal energy that is generated by their metabolism to maintain
homeostatic body temperatures
A. Cooling by evaporation, such as sweating and panting
B. Warming by metabolism
1. muscle contraction and other metabolic activities generate heat
2. shivering warms animals from the heat generated by muscle contractions
C. Behavioral, physiological, or anatomical adaptations that increase an animal's ability to survive
in a certain environment
1. hibernation 2. hair, feathers, blubber
3. staying in the shade 4. restrict activity to night
DIVERSITY, P. 2
Heterotrophs and Autotrophs - Page 106
A. Living systems require free energy and matter to maintain, grow, and reproduce
B. Energy deficiencies are detrimental to individual organisms and can also cause disruptions at the
population and ecosystem level
C. Heterotroph and Autotroph – Words that describe the two possible ways that organisms capture
and store free energy for use in biological processes; how cells can meet their energy needs
D. Heterotrophs
1. These organisms must "take in" nutrition
2.they capture free energy that is present in carbon compounds produced by other organisms
3. includes all animals, all fungi, and many protists and bacteria
E. Autotrophs
1. these organisms capture free energy from physical sources (simple inorganic substances)
in the environment and then make their own food (energy-rich organic molecule glucose)
2. Two different kinds of autotrophs
a. Photosynthetic autotrophs
1) organisms that capture free energy present in sunlight and use it for their
synthesis reactions to produce glucose (during photosynthesis)
2) includes plants and several types of protists and bacteria
b. Chemosynthetic autotrophs
1) organisms that capture free energy from small inorganic molecules (such
as sulfur or methane) present in their environment (this process can occur in the absence of oxygen)
2) includes certain groups of bacteria
Prokaryotes vs Eukaryotes – Pages 56-59
A. Similarities between prokaryotic cells and eukaryotic cells
1. Both have an outer membrane, called the cell membrane or the plasma membrane
2. Both have DNA as their genetic material (the hereditary information) that directs a cell's
activities and enables it to reproduce, passing on its characteristics to its offspring
3. Both have cytoplasm - the fluid material inside the cell that contains the organelles
4. Both have a large variety of molecules in their cytoplasm
5. Both have ribosomes in their cytoplasm. The function of the ribosomes in both types of
cells is to assemble proteins
6. All prokaryotes have a cell wall outside the cell membrane, and some eukaryotes have a
cell wall outside the cell membrane
B. Differences between prokaryotic cells and eukaryotic cells
1. Prokaryotes
a. these cells are much smaller than eukaryotic cells
b. the chromosome (DNA) is localized in a distinct region known as the
NUCLEOID, which is NOT surrounded by a membrane
c. they lack internal membranes and membrane-bound organelles; they only contain
one simple organelle - the ribosomes
d. prokaryotes belong to the either the Domain Bacteria or to the Domain Archaea
2. Eukaryotes
a. these cells are much larger than prokaryotic cells
b. the chromosomes are found in the nucleus, which is surrounded
by a double membrane, the NUCLEAR ENVELOPE
c. they contain a variety of complex organelles
d. eukaryotes belong to the Domain Eukarya and to the Kingdoms Protista, Fungi,
Plantae, and Animalia
DIVERSITY, P. 3
The following organisms are organized from
primitive to advanced
Domain Eukarya
KINGDOM PROTISTA - CH 22
I. Characteristics
A. Organisms in this kingdom may be plantlike, animallike, funguslike, unicellular, or multicellular
B. are eukaryotes
C. in many cases, the evolutionary relationships among the groups are weak, poorly understood or
both
D. They all live in an aqueous environment
II. Animal-like protists
A. Are heterotrophs - they consume either living cells (thus being predatory or parasitic) or dead
organic matter
B. all are unicellular
C. Major Examples
1. Trypanosoma page 354
a) causes African sleeping sickness - it is transmitted by the tsetse fly
b) they propel themselves by twirling or lashing one or more hair-like flagella
2. Amoeba page 366
a)have pseudopodia (extensions of their cell membrane), or false feet, for locomotion
b) they encircle their food and absorb it by phagocytosis
3. Plasmodium p. 359
a) causes malaria
b) part of its life cycle is in mosquitoes and part in humans
c) all members are nonmotile and parasites of animals
4. Paramecium page 356
a) they have cilia, which they use for moving
b) have specialized structures such as a mouth pore, gullet, and anal pore
c) has a contractile vacuole for osmoregulation (controlling the amount of water in
the organism)
II. Plantlike protists – The Stramenopiles
A. all obtain energy from photosynthesis - are photosynthetic autotrophs
B. all have chlorophyll a (which is a pigment molecule that captures sunlight)
C. Kinds of plantlike protists
1. Golden algae – the Chrysophytes page 360
a) have the following pigments for photosyntheis: chlorophyll a, chlorophyll c
carotenes, xanthophylls, fucoxanthins
b) are golden yellow
c) have one or two flagella used for movement
d) unicellular
2. Euglena page 354
a) have one to three flagella (for movement) at their apical (leading) end
b) Are usually autotrophic, but can become heterotrophic in the absence of light
c) some have an eyespot, that permits phototaxis - the ability to move in response to
light
d) unicellular
DIVERSITY, P. 4
3. Dinoflagellates page 358
a) have two flagella for movement
b) some are bioluminescent
c) unicellular
d) have chlorophylls a and c (pigments used in photosynthesis)
4. Diatoms page 360
a) have shells that consist of silica b) unicellular
5. Rhodophyta (red algae) page 363
a) contain red accessory photosynthetic pigments called phycobilins
b) multicellular
6. Brown algae page 361
a) some of these are extremely large - example - sea kelp (giant seaweed)
b) multicellular
c) have tissues that resemble roots and leaves
d) have air bladders to help them float
7. Green algae page 364
a) have both chlorophyll a and b (photosynthetic pigments)
b) have cellulose cell walls
c) there are examples of trends toward multicellularity - some live as colonies of
cells
d) examples - sea lettuce, Volvox, Spirogyra
e) are believed to be the ancestors of plants
f) some have alternation of generations (see explanation in Plants)
KINGDOM FUNGI - CH 24
I. Characteristics
A. grow as filaments called hyphae (singular, hypha)
B. a mass of hyphae is called mycelium (plural, mycelia)
C. some fungi have septa (singular, septum), or cross walls, which divide the filament into
compartments containing a single nucleus
D. Cell walls of fungi contain chitin - a polysaccharide
E. Are either parasites or saprobes
F. Many parasitic fungi have hyphae called haustoria that penetrate their host
II. Lichens
1. mutualistic associations between fungi and algae
2. the algae provides sugar from photosynthesis
3. the fungus provides water and protection from the environment
III. Mycorrhizae
1. mutualistic associations between fungi and the roots of plants
2. the plant provides sugars from photosynthesis
3. the fungus increases the ability of the roots to absorb water and minerals, especially
phosphorus
DIVERSITY, P. 5
OVERVIEW OF ANIMAL KINGDOM
I. CHARACTERISTICS OF ALL ANIMALS
A. multicellular heterotrophs
B. principal mode of nutrition is ingestion
1. digest food in internal cavity
2. store food reserves as glycogen or fat
C. develop in a series of stages
II. SYMMETRY page 406
A. Radial symmetry
1. The regular arrangement of parts around a central axis such that any plant passing through
the central axis divides the organism into halve that are approximate mirror images 2. Found in Cnidarians (Coelenterata) and adult echinoderms
B. Bilateral symmetry
1. A body form in which the right and left halves of an organism are approximate mirror
images of each other
2. Top of organism = dorsal Bottom of organism = ventral
"Head" end = anterior "Tail" end = posterior
III. CEPHALIZATION = the concentration of sensory and nerve cells and of structures associated with
feeding at the anterior end of an animal
IV. DIPLOBLASTIC VS. TRIPLOBLASTIC page 593
A. Diploblastic - Have only 2 embryonic tissues (also called germ layers) - ectoderm and endoderm 1. ectoderm - gives rise to covering tissues, lining tissues, nerve tissues
2. endoderm - gives rise to digestive structures
B. Triploblastic
1. these organisms have a third embryonic tissue (mesoderm) in addition to the other two 2. mesoderm - gives rise to muscles and most other parts of the body
C. Three groups of Triploblastic Animals - based upon the presence or absence of a body cavity
(called a coelom) in addition to the digestive cavity
1. Acoelomates
a. is the simplest arrangement
b. Tissues derives from the 3 germ layers are packed together and there is no body
cavity other than the digestive cavity
c. Phylum Platyhelminthes (flatworms, planaria, tapeworms)
2. Pseudocoelomates
a. Have an additional cavity (the pseudocoelom) that develops BETWEEN the
endoderm and the mesoderm
b. Phylum Nematoda (roundworms)
3. Coelomates
a. Have a fluid-filled cavity that develops WITHIN the mesoderm
b. Within the coelom, the digestive tract and other internal organs are suspended by
double layers of mesoderm called mesenteries
c. Phlya Mollusca, Annelida, Arthropoda, Echinodermata, and Chordata d. Are put into one of two groups - Protostomes or Deuterostomes
D. Fig. 25-6 page 406 and Fig. 25.7 page 407 Important Diagrams!
DIVERSITY, P. 6
ANIMAL PHYLA
LISTED FROM LEAST EVOLUTIONARILY ADVANCED TO MOST EVOLUTIONARILY ADVANCED
VI. PHYLUM PORIFERA page 408
A. aquatic invertebrates called the sponges
B. Have no digestive system: They are Filter Feeders
1. feed by filtering water drawn through the pore cells in the sponge wall by flagellated cells
called choanocytes (collar cells)
2. Water exits through an opening called the osculum
3. Choanocytes pass the food to amoebocytes, which wander between the two cells layers of
the sponge wall, digesting and distributing nutrients.
C. Sponge wall contains spicules, skeletal needles made from CaCO3 or SiO2. These deter predators
and provide structural support for the sponge
D. Have no organs or tissues; Since the cells of the Porifera are not organized in a coordinated
fashion to form tissues, they are classified as parazoa
E. have no defined respiratory system, but they perform gas exchange by diffusion – directly
between environment and the cells of the sponge
F. have no defined circulatory system (to transport nutrients, O2, and CO2 around the organism’s
body), but molecules enter and exit the organism by diffusion directly with the outside environment
G. have no defined nervous system (sending and receiving signals), but there are a few chemical
signals that get sent from cell to cell
H. excretory system: get rid of ammonia and other wastes by diffusion thru the surface of the body
I. have multiple, nonspecific immune responses, but they lack pathogen-specific defense responses
J. are invertebrates, asymmetrical, ectothermic, diploblastic
VII. PHYLUM CNIDARIA (used to be called Coelenterata) page 410
A. aquatic invertebrates that include the jellyfish, sea anemones, corals and hydras
B. there are two body forms
1. medusa
a. a floating, umbrella-shaped body with dangling tentacles typical of jellyfish
b. much like an upside down polyp
2. polyp - a sessile, cylinder-shaped body with rising tentacles typical of a sea anemone
C. have tissues, but no organs
D. Nematocysts – cells that shoot out barbed, hair-like projections with poisonous tips - used for
food collection and protection
E. Have a simple nervous system - Have a nerve net capable of sending signals
F. Digestive system consists of a Gastrovascular cavity that only has one opening (food goes in and
wastes go out the same opening)
G. Have no defined respiratory system, but they perform gas exchange by diffusion – directly
between environment and the cells of the sponge
H. Have no defined circulatory system (to transport nutrients, O2, and CO2 around the organism’s
body), but molecules enter and exit the organism by diffusion directly with the outside environment
I. Have a Mesoglea, a poorly developed third layer, is between the endoderm & ectoderm
J. excretory system: get rid of ammonia and other wastes by diffusion thru the surface of the body
K. have multiple, nonspecific immune responses, but they lack pathogen-specific defense responses
L. invertebrates, radial symmetry, ectothermic, diploblastic
DIVERSITY, P. 7
VIII. PHYLUM PLATYHELMINTHES page 412
A. aquatic invertebrate group that consists of 3 kinds of flatworms - free-living flatworms, flukes,
and tapeworms
B. Free-living flatworms (not parasites)