Chapter 7
Classification by Evolutionary
Relationship
 By far the most familiar is the frame work created 250
years ago by Linnaeus
 Organisms grouped in a taxon show a high degree of
similarity
Kingdom
Phylum
Class
Order
Family
Genus
Species
Binomial nomenclature
2
Domains of Life
Kingdom Animalia
 ~3 million species, maybe up to 30 million
 Eukaryotes:
 DNA enclosed in nucleus
 Heterotrophs:
 Must consume organic matter to maintain cellular
metabolism
 Metabolism = all the chemical reactions that take place in an
organism.
 Multicellular (mostly all)
Kingdom
Animalia
Kingdom Animalia
Must eat
(no photosynthesis)
Kingdom Animalia
Multicellular
Kingdom Animalia
No cell walls
Kingdom Animalia
Some asexual reproduction
Kingdom Animalia
Most Sexual reproduction
Vertebrates
 3% of animal species
 Phylum Chordata





Amphibians
Reptiles
Fish
Birds
Mammals
Invertebrates
 = No Backbone
 97% of all animal species are
invertebrates
 Most species are Marine
 Ex:
SYMMETRY
Levels of Cell Organization
 Cell Level –cells have different functions
 Tissue Level – cells organize into groups that carry
out specific functions.
 Organ Level – tissues organize into organs which
coordinates with other organs to carry out specific
processes.
Phylum Porifera
=Sponges
 =“pore bearing”
 No symmetry = asymmetrical
 Structurally simplest animals
 No organs or true tissues,
 cell level, but specialized!
 Many pores
Phylum Porifera
Sessile =
Suspension Feeders =
Filter feeders = Type of suspension
feeder.
Water is actively pumped or filtering
structures are swept through water
-- food particles taken out of water
-Consume plankton and other organic
materials
Sponges
Structure: Spicules &
Spongin
•Spicules=
• Siliceous or Calcerous structures
• Support!
• Vary in shape and size
Spongin =
Sponge Anatomy
Ostia (Ostium) =
Osculum=
Pinacocytes=
Porocytes =
Sponge Anatomy
Choanocytes/Collar
cells =
Amebocytes=
Water Flow in
Sponges
1.
2.
3.
4.
Sponge form and skeletons
Characteristics
 Branching tubular, volcano
-
like masses
 Encrusting sponges are thin
brightly colored growths on rocks
 Glass sponges live anchored in deep water sediments
& have siliceous spicules
 Boring sponges bore thin channels through calcium
carbonate such as oysters shells and corals
Asexual Reproduction
Some sponges form new
individuals after their
cells are separated from one
another.
Sponge Reproduction
Sexual
Asexual
 Produce gametes = the
 Budding = parent develops
small growths that eventually
break off and become separate
individuals.





reproductive cells.
Specialized collar cells or
amebocytes turn into gametes
Male gamete = sperm, produced
by the testes.
Female gamete =egg, produced
by the ovaries
Most hermaphrodites, produce
both kinds of gametes.
Broadcast spawning, sperm
released into water.
Sexual reproduction cont.
 Early stage of development happens inside sponge
 Embryo released into water as planktonic larva and
drifts with currents.
 Settles on bottom and grows into a new sponge
Fig. 7.4
Sponge Habitat
 Poles to the Tropics
 Most in shallow tropical waters
Sponge Use
 Some sponges harvested in Gulf of Mexico and eastern
Mediterranean
 The spongin are the fibers that remain after death of
sponge