Lecture Test 3 Flashcards
protostome development
blastopore develops into mouth
protostome cleavage
spiral
protostome embryo
mosiac, cell state determined early on
protostome coelom
tissue splits open creating new space, schizocoelous
deuterostome development
blastopore develops into anus
deuterostome cleavage
radial
deuterostome embryo
regulative, indeterminative
deuterostom coelom
digestive tract forms, has bubble that expands, forms by out pocketing, entercoelous
lophotochozoa meaning
locophore: modified tentacles
trocophore: larva
phyla in lophotochozoa
platyhelminthes, annelida, mollusca
Ecdysoza meaning
ecdysis: molting
phyla in ecdysoza
arthropoda and nematoda
coelom
a body cavity completely surrounded by mesoderm
acoelomate
mesoderm completely fills the blatocoel and a coelom never forms
pseudocoelom
mesoderm lines only one side of the blastocoel, leaving a fluid filled blastocoel next to the gut
fluid filled cavity surrounding gut
complete digestive system
inward movement of the archenteron continues until the end of the archenteron meets the ectodermal wall of the gastrula. ectoderm and endoderm layers join together,, this joining produces an endodermal tube which now has two openings
incomplete gut
gut opens only at the blastopore, gvc
monoecious
having bot male and female gonads in the same organism
dioecious
having male and female gonads in separate individuals
general features of platyhelminthes
free living and parasitic, marine and freshwater, bilateral symmetry, body flattened dorso-ventrally, triploblastic, acoelomate, syncitial tegument, incomplete gut, monoecious, no respiratory, circulatory or skeletal system
circular, longitudinal and dorsoventral muscles
four classes in platyhelminthes
turbellaria, trematoda, monogenea and cestoda
features of turbellaria
circular, longitudinal and dorsoventral muscles
cilia present
hydrostatic skeleton/ muscle
free living
features of trematoda
parasitic
loss of cilia
doesnt have to seek out food, attaches to prey
consist of flukes
features of monogenea
parasite to fish, one host
modification of anterior sucker
stay on outside
features of cestoda
loss of digestive system continuously produced reproductive segments scolex germinating zone parasitic no GVC
protonephridium
contain flame cells, cup shaped with a tuft of flagella extending from the inner face of the cup
flagella drive fluid down the collecting ducts, microvilli absorb nutrients and what ever isnt absorb exits body
collecting cups join together
amplification
asexual reproduction in intermediate host, increase numbers
metamerism
division of body into segments divided by septa
the derived is tagmata which are functional units in arthropods
general features of annelids
protostomic, eucoelomates, metameric, closed circulatory system, hydrostatic skeleton, contain setae
classes of annelids
polychaeta, oligochaeta, hirudinea
features of polychaeta
marine, benthic, can be errant or sedentary, well developed head, contain parapoda, actively seeking prey
features of oligochaeta
has calciferous gland, chloragen tissue, few setae, reduced head, mostly terrestrial
features of hirudinea
highly modified annelid, modified digestive tract, freshwater, dorso-ventrally flattened, loss of setae, monoecious, anterior and posterior suckers, loss of septa, partially parasitic
passage of food in digestive system of annelids
mouth, pharynx, esophagus, crop, gizzard, intestine, anus
how does gas exchange work in annelids
goes across skin
how does the circulatory system work in annelids
closed, dorsal vessel is a pumping organ and functions as a heart, recieves blood from vessels of the body wall and digestive tract and pumps it into aortic arches
aortic arches function is to maintain a steady pressure of blood in ventral vessel
ventral vessel, serves as aorta, receives blood from the aortic arches and delivers it to brain and rest of body
metanephridia in annelids
the nephrostome, ciliate funnel, cilia collect wast from coelom and drawn into nephrostome and tubule go through many tunnels to collect particles to be reabsorbed and what is left over goes through nephridiopore and exits body
prostomium
has the eyes, tentacles, and sensory palps
part of a two part head, sits in front of peristomium
pygidium
terminal portion containing anus
chloragen tissue
stores carbohydrates and can see as yellow tissue along dorsal vessel
movement in annelids
contractions of circular m. in anterior end lengthen the body pushing the anterior end forward where it anchors
anchoring is accomplished by contraction of longitudinal m. in forward segments, segments become short and wide
setae project outward, dig into walls of burrow to anchor forward segment
contractions of long m. then shorten the rest of the body pulling the posterior end up behind the anchored anterior region
why are hirudineas different from other annelids
loss of septa and setae
anterior and posterior suckers
dorsoventrally flattened
features of gastropoda
most diverse, shell or no shell, carnivore, herbavore, detrivore, marine, aquatic, and terrestrial, monoecious or dioecious, torsion (bilateral asymmetry), open circulatory system
features of polyplacophora
about 1000 species, body is dorsoventrally flattened, dioecious, 8 plates make shell, mostly on rocks
features of cephalopoda
closed circulatory system, sepia, chromatophores, complex behaviors, very good vision, radula modified into beak, shells modified or reduced or even absent, quick growth rate
features of scaphopoda
tooth/tusk shells, all marine (subtidal), benthic, univalve with two openings, continuous mantle, no gills, respiration occurs across mantle, tentacles present as captaculum, dioecious
general features of molluscs
free living, mostly bilaterally symmetrical, triploblastic, complex digestive system, mono and dioecious, open circulatory system
trocophore
ancestral larve
veliger
derived larva, butterfly looking
gastropoda and cephalopoda
mollusca radula
tonguelike organ, ribbonlike membrane bearing a surface of tiny backward pointing teeth used for feeding, complex muscles help move the radula, the teeth can scrap, tear or cut.
function: to rasp fine particles of food material from hard surfaces and to serve as a conveyer belt for carrying particles in a continuous stream toward the digestive tract
the teeth wears away anteriorly, new rows of teeth are continuously replaced by secretion at its posterior end
water flow in bivalve
flows through incurrent siphon, enters the mantle cavity and then goes through gills where particles are picked up and then water exits excurrent siphon
how digestion works in bivalve
filter feeders
incurrent siphon, particles filtered through gills, ciliary tracts direct currents to tiny pores in gills, labial palps secrete mucous which entangles particles going through gills, enters into mouth, esophagus, stomach, style sac in stomach secretes crystaline style which spins and keeps contents in stomach mixed, helps digest enzymes, enters intestine, exits via excurrent siphon
function of gills
generation of current, capillaries (hemocoel) gas exchange, filer food particles and sort by size from water stream they created and direct food particles forward towards mouth
outside layer of shell in bivalve
periostracum
middle layer of shell in bivalve
prismatic layer
inner layer of shell in bivalve
nacreous layer, secreted by mantle, soft
what type of molluscs are not shelled
slugs and nudibranchs
what are the two type of shells
univalve and bivalve
what are the two types of symmetry in shells
planospiral and conispiral
what is planospiral
all whorls lay in one single plane, bilaterally symmetrical
what is conispiral
each succeeding whorl is at the side of the preceding one, bilaterally asymmetrical, the gill, atrium and kidney of right side have been loss
how does bilateral asymmetry occur in gastropods
Torted exhibit bilateral symmetry, unbalance weight shift for snail to fit into shell, causing internal anatomy to change
detorsion
derived from torted ancestors, derived evolutionary reversal
cephalopod sepia
melanin pigment, used as defense mechanism
cephalopod closed circulatory system
one pair of gills (no cilia), capillaries conduct blood through the gill filaments, entire systemic circulation before the blood reaches the gills, developed branchial hearts at the base of each gill to increase the pressure of blood going through the capillaries
cephalopod beak
radula modified into beak, when capture prey, beak opens up and crushes it
cephalopod acutely sensitive eyesight
complex eyes with cornea, lens, chambers and retina
cephalopod chromatophores
cells in skin that contain pigment granules, muscles control dispersion of color, wether it is concentrated or diluted
cephalopod complex behaviors
communicate with visual signals
cephalopod highly modified or absent shell
mantle becomes new shell, contains gas chambers that help with buoyancy
function of cataculum
tentacles in scaphopods that sweep through sediment to find food particles
general features of nematodes
pseudocoelmates, parietal peritoneum, free living and parasitic, aquatic, terrestrial, saprobic, not well developed head, dioecious, eutelic, no flagellated cells ever, posess a cuticle, hydrostatic skeleton, longitudinal muscles only, only move one way, nervous, excretory and digestive system
eutelic
adults always made up of same number of cells
how would eutelic help in studies of development
generate mutants to see in what way they are different based on the number of cells, create developmental fate map, shows patterns of differentiation, move cells around
syncitial tegument
acellular and multinucleate, no cell division shown under microscope
significance of cuticle and hypodermis in nematode
cuticle in nematode is a non cellular layer made up of protein (collagen), no markings or patterns, in order to grow cuticle must break away from body,
hypodermis is synicitial, acellular or multinucleate layer
anthozoa are only
polyp, no medusa
cubozoa have what domination in growth
medusae
hydrozoa are both
polyp and medusae
hydrozoa contain
hydra and obelia
scyphozoa are what dominantly
medusae
what are four classes of cnidarians
hydrozoa, anthozoa, scyphozoa, cubozoa
what is a radial canal
extension of gvc
function of oral arm
direct food into mouth
function of ropalium
sensory structure
how does velum work with movement
increases H2O pressure when pushing water out which increases velocity for faster swim
statoliths contain
statocysts
what happens in cell development
cell division
cell differentiation
cell migration
control cell death
schizocoelous
tissue splits open creating new space
enterocoelous
digestive tract forms, has bubble that expands
parapodia contain
notapodium, setae, and neuropodium
torsion
movement of shell 90 degrees or more, causing anus and other internal organs to move, gi tract
