Summary Transes For P1-Final Exam Notes

P2 REVIEWER BIO 044  Auricles – tactile lobes
 Rheoreceptors / Statocysts – current + balance
KEY FEATURES OF CNIDARIANS
OCAR = Ocular + Car sensor (eyes, touch, balance).
“DR CINeMa”
Reproduction
 Diploblastic
 Radial symmetry “FAM”
 Cnidocytes (stinging cells)
 Incomplete gut (one opening)  Fission (asexual, esp. planaria)
 Nerve net  Asexual in hosts (flukes, snails)
 Marine (mostly)  Monoecious (hermaphrodite, cross-fertilization)


Two Forms: Polyp vs. Medusa
CLASSES OF PLATYHELMINTHES
“Polyp = Paa, Medusa = Mantya”
“Ta-Tu-Ce-Mo” (TAtu CEMO)
 Polyp – naka-paa (attached), mouth up,
tube-shaped  Trematoda → Flukes (parasitic, leaflike, 2 suckers)
 Medusa – parang may mantya/umbrella, mouth  Turbellaria → Free-living (planarians)
down, free-swimming  Cestoda → Tapeworms (scolex, proglottids, no gut)
 Monogenea → Fish parasites (opisthaptor hooks)

Important Cells
Sample Parasites & Hosts
“CEN-O”
“Ta-Ta-Schoo-Pa-Fa”
 Cnidocytes → sting
 Epitheliomuscular cells → movement  Taenia saginata → Beef tapeworm (cattle →
 Nerve net → reactions humans)
 Ocelli → light detection  Taenia solium → Pork tapeworm (pigs → humans)
 Schistosoma spp. → Blood flukes (snails →
humans)
Life Cycle of Jellyfish (Scyphozoa)  Paragonimus westermani → Lung fluke (snails →
crabs → humans)
“SPeCiaL PEPa”  Fasciola hepatica → Ruminant liver fluke (snails →
cattle/sheep/goat)
 Sperm + Egg → Zygote
 Planula (larva)
 Colonizes → becomes Polyp
 Ephyra (immature medusa) via strobilation
 Pa → Adult medusa (jellyfish) GENERAL CHARACTERISTICS OF SPONGES

“CAP-WAS”
Classes of Cnidaria
 Cellular level of organization (no true tissues or
“HASC” (Hydro, Antho, Scypho, Cubo) organs)
 Aquatic (mostly marine)
 Hydrozoa → Hydras, Obelia, Man-o-war  Pores (body full of small openings)
 Anthrozoa → Corals, anemones (all polyps)  Water canal system for feeding
 Scyphozoa → “Scalloped” jellies (true jellyfish)  Asymmetrical or sometimes radial
 Cubozoa → “Cube” box jellies (lethal)  Sessile adults (but free-swimming larvae)

GENERAL CHARACTERISTICS OF FLATWORMS Important Cells in Sponges

“FLAT-B” “CAPS-A”

 Flattened dorsoventrally  Choanocytes → collar cells, trap food with flagella
 Lack true body cavity (acoelomate)  Amoebocytes/Archeocytes → digestion & can
 An incomplete gut (no anus) transform into other cells
 Triploblastic (3 germ layers)  Pinacocytes → flat cells that cover the sponge
1) Bilateral symmetry (outer layer)
 Sclerocytes → make spicules (skeletal support)
 Again → Spongocytes/Collencytes → make spongin
Excretion & Osmoregulation fibers

“P-FCE”
Canal Systems
 Protonephridia
 Flame cells (nag-fi-flame ang cilia)  “A-S-L” (Asconoid → Syconoid → Leuconoid)
 Collecting ducts  Asconoid → Simplest, tube-shaped, small
 Excretory pores  Syconoid → Thicker walls, canals
 Leuconoid → Most complex, with chambers, largest

Nervous System & Senses
Reproduction
“OCAR”
“BaGS”
 Ocelli – eyespots (light)
 Cerebral ganglia – primitive brain  Budding (external)

,  asexual → regeneration / fragmentation Mnemonic: “Barefoot → hookworm enters your foot.”
 Gemmules (dormant buds, in freshwater sponges)
 Sexual → sperm + egg → parenchymula larva 4. Trichinella spiralis – Pork worm

Think: Spiralis = spiral → larvae coil in muscle like a
spring.
CLASSES OF PORIFERA
Mnemonic: “Undercooked pork → muscle pain.”
“Ca-He-De” (like “Candy”)
5. Pinworm (Enterobius vermicularis)
 Calcarea → calcium carbonate spicules, all canal
types Think: Pinworms = “itchy pin in the butt.”
 Hexactinellida → 6-rayed silica spicules, “glass
sponges” Mnemonic: “Kids scratch at night → eggs on hands →
 Demospongiae → largest class, leuconoid type, reinfection.”
commercial bath sponge
6. Filarial worms (Wuchereria, Dirofilaria)

Wuchereria bancrofti → Elephantiasis ; (mosquito bite
GENERAL FEATURES OF NEMATODES → swollen legs/genitals)
(ROUNDWORMS)
Dirofilaria immitis → Dog heartworm (mosquito →
“CUTI-P” worms clog dog’s heart)

 Cuticle → tough outer coat (shed when growing) Mnemonic: “Mosquito = microfilaria Uber ride.”
 Unique body shape → cylindrical, threadlike
 Triploblastic → 3 germ layers ✅ So, in short:
 Intestine is complete (mouth → anus)
 Pseudocoelom → “fake cavity” (organs floating, not  Ascaris → soil → intestines/lungs
attached)
 Toxocara → pets → larvae wander in humans

Movements  Hookworms → barefoot → skin → intestine →
anemia
 Only longitudinal muscles → move in a whip-like
motion  Trichinella → pork → muscle cysts

 Pinworm → itchy butt at night
Nervous & Sensory
 Filarial worms → mosquito → blood/lymph →
“APP” elephantiasis or dog heart disease

 Amphids → at the head (sensory pores, smell/taste)
 Phasmids → at the tail (only in parasitic worms) GENERAL FEATURES OF ANNELIDS
 Papillae → tiny bumps, sense touch
“SMART WORM”
Think: Nematodes use their “APP” to sense the world
(like a phone app with head, tail, touch sensors).  Segmented (metameric body, little rings)
 Metanephridia (better excretion than
Reproduction flatworms/roundworms)
 Aortic arches (“hearts,” 5 pairs in earthworms)
“DISCO”  Respiration through skin (or gills in some marine
worms)
 Dioecious (male and female separate)  True coelom (eucoelomate, organs well organized)
 Internal fertilization  Well-developed nervous system (brain + ventral
 Spicules in males (needle-like structures for mating) nerve cord)
 Cuticle molting during growth  Organ-system level
 Ova/eggs tough → can survive harsh environments  Red blood (hemoglobin in blood vessels)
 Moist skin needed for gas exchange
Think: Nematodes love “DISCO” parties → males and Think: Earthworms are “SMART WORMs” because
females separate, but meet for mating inside. they’re organized, segmented, and even have red blood.

Major Human Parasites & How to Remember Them Important body parts

1. Ascaris lumbricoides – “Large human roundworm”  Prostomium → lip before mouth (“pro” = in front)
 Peristomium → 1st true segment with mouth
Think: Ascaris = “a scary worm” → comes from  Pygidium → last segment with anus
poop-contaminated soil → travels to lungs → may even
crawl out nose. Think: “Pro-Per-Py” = Front → Middle → End.

2. Toxocara canis/cati – Dog & cat roundworms Digestive Tract (Earthworm)

Think: Toxocara = “toxic pets” → humans get infected “ME-CGI-A”
accidentally → larvae wander in body = visceral larva
migrans or in eyes = ocular larva migrans.  Mouth
 Esophagus
3. Hookworms (Necator, Ancylostoma)  Crop (storage)
 Gizzard (grinds food)
Hookworms “hook” into your intestines → suck blood →  Intestine
cause anemia & weakness.  Anus