Lab Ex 38 Survey of the Animal Kingdom - Phyla Mollusca & Annelida Flashcards
Phyla Mollusca & Annelida
have coelomic body cavity surrounded by mesoderm; contain complex systems of organs and compartments
Protostomes
include phyla mollusca, annelida, and anthropoda; have well-developed nervous, circulatory, excretory, reproductive, and digestive systems
Deuterostomes
include phyla Echinodermata, Hemichordata, and Chordata
Mantle
mollusks such as snails, clams, octopuses, and squids are soft-bodied animals with this specialized layer of epidermal cells that secretes a shell
Open Circulatory Systems
blood pools in sinuses and bathe the organs directly; have a few large vessels and a heart, but no smaller vessels and capillaries
Visceral mass
digestive, excretory, and reproductive systems & sensory structures
Foot
ventral, muscular, often highly modified; used for locomotion
Head
some mollusks have; some don’t
Radula
horny-toothed organ in the mouth; scrapes food (algae) from rocks
Incurrent siphon & Excurrent siphon
mantles of the left and right valves join posteriorly to form a ventral ___ ___ & a dorsal ___ ___ that direct water through the clam
Mantle Cavity
the space between the mantle and visceral mass; water flows into this through the incurrent siphon, over the gills, and then dorsally into a space between the visceral mass where gills attach to the mantle; water exits this chamber posteriorly through the excurrent siphon
Hinge & umbo
on the dorsal surface of a clam; latter is toward anterior end
Labial palps
channel food to a clam’s mouth
Segmentation
most distinctive feature of phylum annelida; body of an annelid is divided into repetitive segments (AKA metameres) arranged on a longitudinal axis and divided by septa
Setae
small, bristlelike appendages often occurring in pairs on lateral and ventral surfaces
Parapodia
each segment of a polychaete bears a pair of fleshy appendages called this; have large surface area, are highly vascularized with blood vessels, and help the polychaete move and respire
Prostomium
mouth of oligochaetes is preceded by this fleshy lobe
Peristomium
posterior to the mouth of oligochaetes is this first body segment
Clitellum
series of swollen segments at the anterior third of the body
Seminal vesicles
where sperm mature in earthworms
Male gonopores
where sperm exit an earthworm (segment 15)
Seminal receptacles
each side of segment 10 on an earthworm; store sperm temporarily
Female gonopores
segment 14 of an earthworm; clitellum secretes a mucous band that slides anteriorly and picks eggs up from this + stored sperm from seminal receptacles
Cocoon
after the eggs are fertilized in the mucous band, the worm releases it as this
Pharynx
segments of an earthworm’s digestive tract are fused and specialized to form a muscular _____ (for suction and ingestion of food)
Esophagus
for transport of food in an earthworm
Crop
for food storage and some digestion in earthworms
Gizzard
for maceration or crushing of food in earthworms
Intestine
for absorption of nutrients
Ventral nerve cord
spinal cord in earthworms (on underside)
Nephridia
small, white, convoluted tubes; found on the inner surface of each segment of an earthworm; function like kidneys (collect and release excretory wastes)
Nephrostomes
ciliated, funnel-shaped structures on the ends of the nephridia that gather waste products that are released through external pores called nephridiopores
Nephridiopores
external pores where waste products are released from earthworms
Dorsal & Ventral Blood Vessels
blood vessels above and below the intestine in earthworms; main vessels of the closed circulatory system
Lateral hearts
5 of these in earthworms; promote blood circulation no more than the dorsal and ventral vessels
Typhlosole
digestive tract of earthworms has an internal fold of tissue called this, which arises from the dorsal wall; creates a U-shaped intestinal lumen, doubles the surface area for absorption
Spermatophore
two leeches intertwine and species with copulatory organs inject a packet of sperm called this into the female gonopore