Biodiversity Test 3

§ Unicellular or colonial protozoa

§ Locomotion by flagella or pseudopodia (or both)

§ Autotrophic and heterotrophic

§ Homokaryotic (possess a single nucleus

§ Subphylum Sarcodina

§ Subphylum Mastigophora

§ Amebae (plura) or Amebas (plural, but less commonly used)

§ Naked amebae used in lab with large false feet

• § Features : gel and smooth cytoplasm, ecto- and
• endoplasm, pseudopods, food vacuoles (digested by lysozomes), contractile
• vacuoles (expel H2O like a kidney)

• § They crawl; 3D gels slide like actin/myosin to make
• pseudopods travel

§ Amebae can carry a test (a housing structure used as protection, produced by the organism). They grab particles and build glue and housing structure

§ They feed on spirogyra

§ Species are distinguidhes by size or type of particles used

• § Sea urchins are another example; they have fused
• ossicles (small bones)

§ Phagocytosis (“cell eating”); uses pseudopods to grab food

§ Morphology=shape

§ Microtubules are 25 nm in length

Class zoomasrigophorea (Zooflagellates)

Class Phytomastigophorea (Phytoflagellates)

1-2 flagella

Store products as starch or paramylon

Primarily free-living

• Ex. Bacteria (food source) taken away, Paramecia will grow pseudopods to “run away” or grow
• flagella (ameboid)

§ Outer pellicle

Numerous flagella

Store anabolic products as glycogen

Free-living, many are parasites or symbionts

§ 1/3 of weight of termite

§ Peranema- feeds on euglena (a phytoflagellate)

§ Shape constant (or rigid) surrounded by pellicle)

§ Cilia for locomotion and feeding (infrastructure)

• § Two distinct types of nuclei (macronucleus- vegetative
• function, vs micronucleus-sexual reproduction + or -)

§ Asexual reproduction by binary fission

§ Sexual reproduction by conjugation (like in spirogyra)

Paramecium

§ Fires trichocyst

Flower looking. Will break off stalk and swim away

Cirri- larger than cilia. Can walk instead of swim

Didinium- eats paramecium

§ Shoot out cytostome

• § Sit and spin because it ate too much! Will eat again
• in 3 or 4 hours

§ Metazoan at the cellular grade of construction; without true tissues; adults asymmetrical or radially symmetrical

§ Cells tend to be totipotent

§ With unique flagellated cells—choanocytes—that drive water through canals and chambers constituting the aquiferous system

§ Adults are sessile (don’t move) suspension-feeders (filter feeding) larval stages are motile

§ Middle layer—the mesohyl—variable, but always includes motile cells and usually some skeletal material

§ Skeletal elements, when present, composed of calcium carbonate, silicon dioxide, and/or collagen fibers

§ 1 metazoa(have more than 1 cell)

§ 2. have mesoglia. Similar to mesohyll

§ 3. have radial symmetry

§ 4. nematocysts. Stinging cells. Only group that has these

• § 5. have a body cavity that is called the gastrovascular cavity. Single opening that serves as both mouth and anus. Incomplete digestive tract. Goes into coeleneron where it is digested, and then
• goes back through same epithelium where it was brought in
• Class Anthozoa
• Class schyphozoa
• Class Hydrozoa

corals, sea anemones

largest class in the phylum cnidaria over 15,000 species

exclusively marine forms

polyp of polypoid stage only, the medusa stage is absent (only class that does not have metagenesis)

reproduction- sexual and by budding (asexual). Fragmentation- in poor conditions (water quality bad), will reproduce asexually. Will move in one direction, but leave a little piece where it started. Will produce a clone of itself

Jellyfish

Primarily marine (few in freshwater, but very rare)

Float usually in open seas

Tentacles numerous to few

Aurelia common genus throughout warm seas

Details of life cycle- metagenesis

The hydrozoans (Hydra and Obelia common genera)

Marine and freshwater forms common

Division of labor

• ¨
• Zooids=polyps

Coloniality

Polyp or medusoid stages in life cycles

Polyp of polypoid form (or morph) most common

Zooid types and functions

§ Gastrozooid- feeding zooid

§ Gonozooid- reproductive zooid

§ Dactylozooid- defense zooid, protects the colony***

• § Parasitic or free-living, unsegmented
• worms

• § Triploblastic (pertaining to metazoan
• in which the embryo has 3 primary germ layers-ectoderm, mesoderm, endoderm),
• acoelomate (no body cavity), bilaterally symmetrical; usually dorsoventrally
• flattened

• § Complex, though they have incomplete
• digestive track; just absent in some parasitic forms (cestoda)

• § Cephalized (cephalization = defined
• head region), with a central nervous system with a “brain” (a fusion of glial
• cells) and longitudinal nerve cords connected by transverse commissures
• (ladder-like nervous system)

• § With protonephridia (primitive
• excretory/osmoregulatory organ consisting of a tubule terminating internally
• with flame bulb or solenocyte; the unit of the flame bulb system)

• § Hermaphroditic, with complex
• reproductive system; monoecious

• Class Turbellaria
• Class Cestoda
• Class Trematoda

¨ Flatworms/ Planaria

¨ Freshwater, marine, and terrestrial

¨ Dorsoventrally flattened

¨ Carnivorous

¨ Monoecious; mostly cross fertilize for genetic variation

¨ Hypodermic impregnation: can carry a baby anywhere, like the head, back, etc.

¨ Fissiparity (splits in two down the middle) and fragmentation (budding) Ex. Halloween Planaria

¨ Pharynx is the center of the work that digest and excretes food. They can eat each other. Bright colors indicate bad taste (repugnatory glands are toxic). They have lots of mucus glands and are regenerative of body parts

¨ The tapeworms

• ¨ All members are parasitic; about
• 4,500 species

¨ Internal parasites (endoparasites) vs ectoparasites

¨ Parasites of vertebrates primarily

¨ Scolex, head, or rostellum are important taxanomic characters

¨ Proglottids: segments or somites (reproductive units)

¨ No digestive tract

¨ Tegument (an integument, specifically, the external covering, formerly called a cuticle), syncytial (termed a syncyntium—many nuclei are present without any intervening membranes); multinucleated mass of cells formed by rapid mitotic division

• Hermaphrodites; gonochoristic (dioecious) or
• monoecious

¨ the flukes

¨ all parasitic- 6,000 + species

¨ ecto and endoparasites

¨ non-ciliated epidermis

¨ various suckers on body

¨ parasites of fish, foul, mammals

¨ common Chinese liver fluke – Opisthorchis sinesis

¨ pseudocoelomate- not lined by mesoderm

§ triploblasitc, bilateral, unsegmented pseudocoelomates

§ gut completely regionally specialized

• § pharynx modified as a mastax,
• containing jaw-like elements called trophy

• § anterior end often bears variable
• ciliated fields called a corona

§ posterior end often bears toes and adhesive glands

§ protonephridia present, no special circulatory or gas exchange structures

§ males generally smaller than females or completely absent in some species. Parthenogenesis is common (development of egg without fertilization by sperm)

§ marine, freshwater—sessile or free-swimming

• (horse hair worms- look like hair, and found in troughs)
• § triploblastic, bilateral, unsegmentes, and vermiform
• (worm-like) in shape, long and thin

§ cuticle well developed

§ gut reduced to various degrees, always nonfunctional in adults

§ larvae parasitic in arthropods (insects etc)

§ no special excretory, circulatory or gas structures

§ freshwater, some terrestrial, a ver few species in marine environment

§ dioecious

§ Thin, thread-like

§ triploblastic, bilateral, pseudocoelomates

§ body divided into 13 segments called zonites**

§ complete digestive track

• § one pair of protonephridia, no special circulatory or
• gas exchange structures

§ period molting (called ecdysis)

§ dioecious

• § inhabit marine, interstitial (to live between sand
• grains) environments

§ triploblastic, bilateral, unsegmentes

§ with one to many pairs of adhesive tubes

§ cuticle (outer covering or epidermis) well-developed, often forming plates and spines

§ cilia restricted to ventral surface

§ complete digestive track

§ protonephridia present

§ monoecious and a dew dioecious forms known

§ freshwater or marine habitats

• § triploblastic, bilateral, unsegmentes, vermiform
• (=worm-like) pseudocoelomates

§ anterior end with hook-bearing proboscis

§ gut absent

§ protonephridia present, but greatly reduced in numbers compared to other pseudocoelomate phyla

§ dioecious

§ parasites of vertebrates, with very complex life cycles

• § triploblastic, bilateral, vermiform (worm-like)
• unsegmented, pseudocoelomates

§ body round in cross section and the cuticle is complex and some species may shed or molt the cuticle during growth periods

• § gut complete, mouth surrounded by siz lips bearing
• sense organs

§ unique protonephridia called solenocytes

§ no special circulatory or gas exchange structures

§ body walls has only longitudinal muscles

§ dioecious

• § marine, freshwater, terrestrial and parasitic life
• cycles

§ Only have longitudinal muscles

§ Could be 90,000 nematodes inside a brown apple

Triploblastic, acoelomate or coelomate. Bilaterally asymmetrical unsegmented worms

Digestive tract complete with anus

With protonephridia

With lobed, supraenteric cerebral ganglion; and two or more longitudinal, nerve cords connected by transverse commisures

With two or three layers of body wall muscles converges in various ways

With unique proboscis apparatus lying dorsal to the gut and surroung by a coelom-like hydrostatic chamber called the rhynchocoel

With closed circulatory system*********

Most are genochoristic early development typical spiakin eaiter direct or indirect

Brightly colored (warning). Can be very long. Use Retractor muscle. Rincoceal

Bilaterally symmetrical, segmented worms

Digestive tract complete, usually with regional specialization

With a closed circulatory sstem (some have multiple hearts)

Nervous system well developed

• Posess nephridia (many kidneys)- osmoregulatory
• and regulation of nitrogenous wastes

With paired, segmentally arranged setae bundles

Metameric body mass

Monoecious or dioecious

Marine, terrestrial and freshwater species

Metamerism- segmented body plan (anterior- posterior). Each segment almost the same. Allows them to move through peristalsis

• Class Polychaeta
• Class Hirudinea
• Class Oligochaeta

• Polychaete worms (many setae-
• extensions of the cuticle)

Setae = chaetae

Primarily marine (very few freshwater forms

Eversible pharynx –proboscis

Filter feeders

Deposit feeders

Errant forms (motile) Order Errantia

Sedentary forms (sessile) order Sedantaria

Clamworms most common genus – Nerreis

Sabellids (no operculum) vs Serpulids- (possess operculum = door)

Dioecious

§ Leeches

§ 2 suckers- usually anterior and posterior

§ Ectoparasites, but can also be detritivores (detritus

§ No setae (cuticular extensions)

§ No parapodia, characteristic of the class Polychaeta

§ Reduced coelom

§ Hypodermic impregnation

§ Estivate (go into hibernation if conditions are poor)

§ Monoecious and dioecious

§ Hirudin- anticoagulant like heparin

§ Earthworms, freshwater worms. Lumbricus most common genus

§ 3100+ species

§ Terrestrial and freshwater forms

§ Metamerism- highly developed

§ Setae (=bristles) 1-2 per somite (segment)

• § Peristaltic movement (excellent burrowers and
• swimmers)

§ Lack eyes- possess ocelli

§ monoecious