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are eukaryotic heterotrophs that digest food outside of their
bodies.
1. most are multicellular
2. found all over the world in both terrestrial and marine
environments
3. most are
, breaking down dead
organisms and returning nutrients to the ecosystem
4. composed of a mass of threadlike filaments called
- the hyphae combine to make up the fungal
- the hypha is composed of a chain of fungal cells; it is surrounded by
a PM and a cell wall made of
(a polysaccharide), not
cellulose (plants)
- fungal mycelium can expand very quickly through mitotic growth 
up to a km per day
5. large underground mycelia produce
(mushrooms) above ground  they are a small
extension of the main organism, the mycelia
Fungal hyphae on a leaf
6. Feeding
a. the mycelium has a very high surface area: mass ratio which allows a
fungus to absorb large quantities of nutrients
food
b. it gets nutrients by secreting digestive enzymes and digesting its
of its body
7. Members of fungi may be the largest and oldest organisms on the
planet. A single fungus was found to cover 2200 acres and is
nearly 2400 years old.
Fungal Partners
– Mutualistic relationship between
fungi and vascular plant roots
• Hyphae help transfer phosphorous and other minerals from the soil to the
roots of the plants
• Plant supplies carbohydrates to fungus
– Relationship between fungus and a
photosynthetic partner
• Photosynthetic partner provides carbohydrates
• Fungal partner protects it
5 Groups of Fungi
1.
Chytrids
•
Flagellated spores
•
•
Black bread molds (fast growing molds)
Zygosporangium
2.
3.
Glomeromycetes
•
Tiny tree-like structures called arbuscules
•
•
Sac fungi
Asci
4.
•
Morels, cup fungus
5.
•
•
Club fungi
Basidium
•
Shelf fungi, mushrooms, puffballs
-- Animals are multicellular heterotrophic eukaryotes that lack cell
walls
-- Most reproduce sexually and are mobile
1. characterized by body plan
a.
central axis
symmetry  body parts are arranged around a
b.
images of a central plane
symmetry  body parts are arranged as mirror
Orientation
dorsal  top (back)
ventral  bottom (front)
anterior  head
posterior  tail
Radial symmetry
Bilateral symmetry
2. Body plan vary according to tissues
– 3 layers of tissue
3. Most triploblastic animals have body cavities – fluid filled space that
forms b/w the digestive tract and the outer wall of the body
a.
mesoderm
– body cavity completely lined by
 no body cavity with coelom
 mesoderm lines the body cavity
partially
 have true coeloms
Acoelomates such as Planarians lack a body cavity between
the digestive tract and body wall.
Pseudocoelomates such as nematodes have a body cavity partially lined
by tissue derived from mesoderm.
Note the digestive tract is not covered by mesoderm tissue.
Coelomates such as earthworms have a true coelom, a body
cavity completely lined by tissue derived from mesoderm and surrounding
a digestive tract derived from endoderm.
The coelom separates and suspends the organs from the body, providing
cushioned support and room to grow, as well as separate openings for
the mouth and anus.
4. Classification
a. Invertebrates & Vertebrates (informal)
95% of organisms are
bone/vertebral column
5% are
vertebrates are chordates
 lack a back
 have a backbone; most
Some invertebrate taxa
1.
(formerly Porifera)
- lack true tissues (basal animals)
–
- suspension (filter) feeding
flagellated cells help sweep
water through sponges body
- radially symmetrical
- sessile
- hermaphroditic – individual produces both eggs and sperm
- Asexual and sexual
2.
– jellies, hydras and corals (coelenterate)
- endoderm and ectoderm
- acoelomate
–
stinging cells
- radial symmetry
- incomplete digestion
-2 body plans
a. polyp = cylindrical form that is sessile anchored to
substrate
b. medusa = flattened mouth down version of polyp, free
moving (can contract for movement or drift)
- Asexual and Sexual
polyp
Medusa
3.
– flatworms
- planarians, tapeworms and flukes
- are the simplest bilaterians (bilateral symmetry)
-
have three tissue layers
-
acoelomate
-
true organs (pharynx and excretory system)
-
incomplete digestion
-
asexual and sexual
Flatworms live in marine, freshwater, and damp terrestrial habitats.
Some are parasitic, and others are free-living
4.
– round worms, hook worms
- bilateral symmetry
- three tissue layers, organs and systems
- parasitic or free living
- sexual
–
tough, non-living material that
cover and protect from drying
out
- psuedocoelomate
- a complete digestive tract with a mouth and anus
Nematode and cyst in soybean plant
5.
– molluscs
- bilateral symmetry
- coelomates
- three tissue layers, organs and systems
- complete digestion
a muscular
which functions in
locomotion
,
a
containing most of the
internal organs
A
,
which may secrete a shell
that encloses the visceral
mass
- sexual
Many molluscs feed with a
rasping
, used to scrape up
food.
- circulatory system that pumps blood and distributes nutrients and oxygen
throughout the body
Gastropods, Bivalves, Cephalopods
Figure 18.9a
Visceral mass
Body cavity
Kidney
Heart
Mantle
Mantle
cavity
Reproductive
organs
Digestive
tract
Shell
Radula
Anus
Gill
Foot
Nerve cords
Digestive
tract
Mouth
Basic Body Plan of Mollusc
6.
– segmented worms
ex. Earthworms, leeches
segmentation, the subdivision
of the body along its length
into a series of repeated parts
-
radial symmetry
-
coelomates
-
complete digestion
-
sexual
-
a closed circulatory system in which blood remains enclosed in
vessels throughout the body
a nervous system that includes
a simple brain and ventral
nerve cord
Medicinal leech
7.
– regarded as most successful of all
animal phyla in terms of species diversity, distribution and numbers
- bilateral symmetry
- coelomates
- complete digestion
- segmented bodies – head,
thorax, abdomen
(cephalothorax)
- jointed appendages for
locomotion and
feeding
- sexual
ex. Crustaceans, millipedes, centipedes, scorpions, ticks, mites,
spiders, insects
8.
– starfish, sea stars, sea cucumbers
- radial symmetry (as adult)
and hard, spiny skin
- coelomates
- complete digestion
No segmentation
all marine
- asexual and sexual
- sessile, slow moving as adult / free swimming larvae
- water vascular system
Echinoderms