BIOL 321 LAB Flashcards
(266 cards)
1
Q
a diagram of a hierarchical system of nested sister groups of taxa
A
cladogram
2
Q
meaning of ‘dissection’
A
exposing to view
3
Q
what are dissecting microscopes used for
A
viewing are, relatively opaque objects
4
Q
dissecting microscope lens system is designed to
A
maximize working distance between object lenses and the subject
5
Q
illumination in a dissecting microscope
A
above
side
below
6
Q
side illumination
A
reflected light
7
Q
illumination from below
A
transmitted light
8
Q
compound microscope is used for
A
observing fine details in small specimens that have been rendered transparent
9
Q
compound microscope illumination
A
generally transmitted light
built-in illuminator concentrates light beams through condenser
10
Q
compound microscope objecties
A
scanning (4x)
low power (10x)
high power (40x)
oil immersion lens (100x)
11
Q
most frequent objective used for studying invertebrates
A
low power 10x
12
Q
primary magnification power
A
objective lens
13
Q
Parfocal
A
objects remain in focus when a different objective is rotated into position
14
Q
what does the ocular lens do
A
convert the magnified real image from objective lens into a magnified virtual image
15
Q
objects remain in the centre of the field when a different objective is rotated into position
A
parcentral
16
Q
how to obtain maximum resolution
A
Koehler illumination
center and focus illumination system
17
Q
10x objective field diameter
A
1.6mm
18
Q
40x objective field diameter
A
0.4mm
19
Q
calculate magnification of a drawing
A
size of drawing / size of object
20
Q
calculating scale bar
A
(drawing length)/(specimen length) = (scale bar length)/x
21
Q
Phylum Porifera Classes
A
Class Calcarea
Class Hexactinellida
Class Demospongiae
22
Q
Sponges lack
A
mouth
digestive cavity
nerves
muscles
23
Q
how sponges eat
A
most capture bacteria/phyto. and digest in intracellular food vacuoles
24
Q
‘carnivorous’ sponges
A
Cladorhizidae
eat small zooplankton - break into small pieces, phagocytize, digest with intracellular vacuoles
25
sponge symmetry
some radially symmetric, most asymmetrical
26
sponge body plan
two photo-epithelial layers sandwiching a layer of connective tissue
27
outer surface of sponge body
pinacoderm
28
internal surfaces (canals and chambers) of sponge body
choanoderm
29
connective tissue layer of sponge body
mesohyl
30
cells in outer layer of sponge body
pinacocytes
31
inside of the mesohyl
collagen fibres, ameboid cells, skeletal elements
32
cells in inner layer of sponge body
choanocytes
33
sponge skeletal elements
biomineralized spicules and/or organic cord mesh
34
organic mesh skeletal element of some sponges
spongin
35
choanocyte function
use flagella to propel water through sponge body
| capture and digest food particles suspended in water
36
grades of complexity in sponges
Asconoid
Syconoid
Leuconoid
37
Asconoid
minute
vase-shaped
choanocytes line a central spongocoel
38
central spongocoel
atrium
39
Syconoid
larger
vase-shaped
choanocyte-lined chambers each open directly into central spongocoel
40
Leuconoid
massive form
| spongocoel replaced with extensive system of choanocyte-lined chambers interconnected by canals
41
advantage to sponges increasing surface area
increased efficiency in filter water and capturing food
42
Class Calcarea features
exclusively marine
CaCO3 spicules
all 3 architecture types
individuals can cluster, but live independently
buds occasionally appear at base of mature specimens
43
asconoid Calcarea observed in lab
Leucosolenia
44
syconoid Calcarea observed in lab
Grantia
| Scypha
45
Class Demospongiae
All freshwater sponges
Most marine sponges
Leuconoid
most local intertidal sponges have encrusting growth
46
Demosponge skeleton
anastomosing ropes of proteinaceous spongin and/or siliceous spicules
NO CaCO3
47
Class Hexactinellida
glass sponges
| pinacoderm and choanoderm are syncytial
48
Hexactinellida skeleton
chitin
| 6-pointed silica dioxide spicules
49
syncytium
a multinucleate animal tissue without internal cell boundaries
50
Hexactinellid observed in lab
Aphrocallistes
51
Gemmules
a dormant structure entered in to mostly by freshwater sponges, during times of unfavourable conditions
52
significance of gemmules
more resistant to desiccation/freezing/anoxia
| protect sponge
53
secondary metabolites
organic molecules not part of biochemical pathways involved in metabolism of nutrient molecules
54
Poriferans manufacture secondary metabolites to
deter predators
deter competitors for living space
inhibit pathogens
55
Halichondria secondary metabolites
unpleasant odour when rubbed
| local species
56
why sponges are rarely overgrown by other sessile organisms
defensive chemicals (secondary metabolites)
57
importance of sponge spicules
support- body would collapse without
| taxonomy - shape and mineral composition distinguish species
58
easy way to tell if sponge is Calcarea
acid test (dissolves CaCO3)
59
spicule shapes, axes
suffix -axon
# of axes
monoaxons
triaxons
60
spicule shapes, number of points
suffix -actine
# of points
triactine
hexactine
61
demosponge spicules
most are monoaxons
62
Grantia spicules
triaxon and triactine
63
glass sponge spicules
triaxon and hexactine
64
Carnivorous sponges tend to inhabit
the deep sea
65
shallow-water Cladorhizidae in Salish Sea
Asbestopluma occidentalis
18m
co-occur w/ hexactinellid sponges
66
Asbestopluma occidentalis reproduction
adult disassociates tissues facilitating larval release and dispersal
larvae have actively beating cilia (no swimming observed)
parent reaggregates into spherical balls of undifferentiated tissue that can disperse and settle
67
Asbestopluma occidentalis feeding
observed capturing Artemia nauplii using anisochelae spicules
68
nauplii
first larval stage of many crustaceans, having an unsegmented body and a single eye
69
Subphylum's in Phylum Cnidaria
Medusozoa
| Anthozoa
70
Class's in Subphylum Medusozoa
Staurozoa s.g. to
Hydrozoa s.g. to
Scyphozoa s.g. w
Cubozoa
71
Class's with free-floating Medusae
Hydrozoa
Scyphozoa
Cubozoa
72
Example of Class Hydrozoa from lab
Obelia
| Siphonophores
73
Example of Class Scyphozoa from lab
Aurelia
74
Class's in Subphylum Anthozoa
Octocorallia
| Hexacorallia
75
Class Octocorallia includes the
soft corals
| sea pens
76
Example of Class Hexacorallia from lab
Anthopluera
77
Class Hexacorallia includes the
sea anemones
| stony corals
78
Cnidarian size
1mm - 2m in diameter
79
Cnidaria germ layers
epidermis covers body surface
gastrodermis lines body cavity (GVC)
Mesoglea between
80
Mesoglea
collagen fibres
extracellular matrix
ameboid cells (in most clades)
81
What do Cnidarians have that Poriferans do not
true gut
nerve cells
cnidocysts (unique to them)
82
Cnidarian GVC
digests ingested food
| circulate nutrients and gases throughout body
83
Cnidarian symmetry
most radial
| sea anemones, corals = biradial
84
biradial symmetry
similar parts are located to either side of a central axis and each of the four sides of the body is identical to the opposite side but different from the adjacent side
85
Alternation of generations
in most Medusazoans
asexual polyp stage
sexual medusa stage
polyp, medusa both diploid, only egg is haploid
86
Polymorphism
colonial individuals develop differently morphologically
preform different specialized jobs (feeding, reproduction, defense)
genetically identical - express diff. parts of the genome
87
Cnidarian lifestyle
All carnivorous
| prey capture facilitated by cnidocytes (in high density on tentacles)
88
Nematocyst function
prey capture
defense
aid in digestion
89
Hydra
freshwater
class Hydrozoa
no medusa stage
2 germ layers, cnidocytes only in epidermis
90
Hydra morphology
```
mouth at apex of hypostome
ring of tentacles at base of hypostome
body column, gastric region, stalk
basal disk (adhesive)
budding zone
```
91
hypostome
the oral tip surrounded by tentacles in hydrozoan cnidarians (cone-shaped)
92
Hydra budding zone
junction of gastric region and stalk
| where new polyps arise as asexual buds
93
Hydra reproduction
bud forms on stalk as simple evagination - distal end of bud forms mouth + tentacles - bud drops off
94
acontia
thread-like pieces of the body found near the pedal disc, attached to septal filaments inside the body, at times flow in/out of GVC
95
Medusazoans that stray from typical alternation of generations homology
Staurozoans - free-living medusa completely absent
| Hydrozoa - some members exhibit secondary loss of medusa stage (e.g. Hydra)
96
Morphological character in common with all Medusazoans
linear mitochondrial chromosome
| other Cnidarians, most eukaryotes have circular
97
Scyphozoa
```
scyphomedusa larger, more conspicuous life stage
some freshwater
cnidocytes in epidermis + gastrodermis
gametes originate from gastrodermis
ameboid cells in mesoglea
frilly oral arms
thick mesoglea
```
98
cnidarian medusa swimming
rhythmic contraction of epitheliomuscle cells (circular muscle sheet on underside of bell)
99
manubrium
a tubular structure that contains the mouth
100
Scyphozoa digestion
prey captured with cnidocytes on tentacles/oral arms, transferred to mouth at end of manubrium, ingested, conveyed to stomach, distributed to 4 gastric pouches, partially digested enzymatically - digestion completed intracellularly w/i gastrodermal cells -- then circulated via ciliated gastrovascular canals
101
Scyphozoa gastric pouces
contain short gastric filaments (tentacles) that secrete digestive enzymes
102
Scyphozoa gastrovascular canals
adradial (unbranched)
interradial, perradial (branched)
GV canals connect gastric pouces to ring canal (around periphery of bell)
103
common moon jellyfish
```
Aurelia
floats close to surface
local
short tentacles and manubrium
feeds on small plankton 0.2-2mm
```
104
Aurelia feeding
slow contraction of bell -- draws prey toward medusa -- recovery stroke -- sucks prey into subumbrellar cavity -- captured, subdued by nematocysts in oral arms
feed on smaller organisms than other scyphomedusae b/c of short oral arms
105
sensory cells around bell of Scyphomedusae
rhopalia
8 small 'knobs'
statocyst, pigment spot, cluster of photoreceptor cells, chemoreceptor cell
106
Statocyst
gravity receptor
107
Initiates swimming in Scyphomedusae
rhopalia - neurons in cell bodies - send neurites to swim muscle - initiate swimming pulsation
108
subumbrellar
located beneath the umbrella
109
gonochoristic
dioecious
| male and female reproductive organs in separate individuals
110
Scyphozoan gametes
gonochoristic
gametes arise from gastrodermal epithelial cells in gastric pouches
mature gametes exit through mouth
eggs lodged if pits of oral arms, fertilized, develop into planulae
111
Scyphozoa planulae
ciliated
non-feeding
brief free-swimming stage
settle to bottom, attach to substrate, develop into scyphistoma
112
Scyphistoma
polyp scyphozoa form
feeds
reproduces asexually (budding, strobilation)
113
Strobilation
sequential transverse fissions of oral end of strobila
| strobila is reproducing form of scyphistoma
114
Immature medusae released from strobila
ephyrae
115
Aurelia life cycle
medusa -- egg -- fertilization -- planula -- scyphistoma -- possibly budding -- strobila -- ephyra -- development -- medusa
116
Class Hydrozoa characteristics
polyps usually form colonies
mesoglea lacks cells, cnidocytes
gametes arise from epidermis
no oral arms
117
Hydrozoan medusa
```
Hydromedusae
smaller, deeper bell
many have velum
no rhopalia
concentration sensory cells at base of tentacles (photoreceptor and statocyst)
```
118
velum
rim of muscular tissue projecting inward at peripheral margin of bell
controls size of subumbrellar aperture
119
why do medusa have more sophisticated sensory structures than polyps
because they are motile, they have to constantly monitor their surroundings for danger
120
hydrozoan polyp colony
hydroid
buds remain attached
may exhibit polymorphism
121
feeding hydroid polyps
gastrozooids
122
reproductive hydroid polyps
gonozooids
123
defensive hydroid polyps
dactylozooids
124
living tissue of hydroid
coenosarc (polyp + stem tissue)
125
protective hydroid covering
perisarc
| chitinous sheath surrounding coenosarc
126
hydroid connected to substrate by
stolons - network of horizontal tubes
127
Hydroid in lab
Obelia
128
gonozooid structure
stalk w/ saucer-like medusa buds
| enclosed in transparent, chitinized, vase-shaped theca w/ opening at top
129
Obelia life cycle
dioecious adult medusa - spawn gametes - fertilization - zygote - planula larva - settles - metamorphosis - budding -- form hydroid colony -- gonozooid produces medusa w/ 8 statocysts -- grow/develop tentacles and gonads
130
Class Staurazoa characteristics
```
no alternation of generations
elaborate polyp stage
stalk on exumbrellar surface
tentacles organized in to clusters around bell margin
basal plate secretes adhesive
anchors
```
131
Staurazoa anchors
small knobs around bell
may form temporary substrate attachment
facilitate looping movement
132
Subphylum Anthozoa characteristics
all marine
no medusa
gullet
mesoglea contains amoeboid cells (like Scyphozoa)
GVC subdivided by nematocyst-bearing septa (folds of gastrodermis)
mostly dioecious
133
gullet
actinopharynx
Anthozoan body turns in at mouth to form gullet
muscular
runs down from mouth to GVC
134
Anthozoa coelenteron
GVC
135
siphonoglyph
ciliated groove at one or both ends of mouth
extends into pharynx
used to create currents of water into the pharynx
136
Anthozoa acontia
threads at end of mesenteries below the filaments, other end free, extraordinarily numerous nematocysts, can be protruded through the mouth or special pores in body-wall for defense or paralyses of prey
137
Anthozoan Classes
Class Octocorallia
| Class Hexacorallia
138
Octocorallia
```
aka Alcyonaria
8 complete septa
8 tentacles
all colonial
polyps connected by mesoglea + gastrodermal tube
pinnate tentacles
```
139
Hexacorallia
aka Zoantharia
septa in multiples of 6
non-pinnate tentacles
solitary or colonial
140
solitary Hexacorallia
sea anemones
141
colonial Hexacorallia
hermatypic corals
142
pinnate
side branches
143
Anthozoa reproduction
swimming planula -- settles on substrate -- metamorphosis -- young polyp -- grows to become sexually mature
colonial corals - original polyp buds in to the entire colony
anemones can also reproduce asexually
144
Have cnidocytes in gastrodermis
Scyphozoa - Yes
Anthozoa - Yes
Hydrozoa - No
(secrete digestive enzymes to aid digestion)
145
where is calcareous biomineral deposited in Anthozoans
Hexacorallia - external CaCO3 skeleton under polyps
| Octocorallia - internal CaCO3 spicules w/i mesoglea
146
hydromedusa Aglantha digitale
uniquely evolved giant axons, used to swim in 2 distinct ways (escape, slow)
147
how Aglantha digital can swim in two distinct ways
axons can conduct Ca and Na spikes (at separate times)
148
Phylum Platyhelminthes taxonomy
Class Turbellaria s.g. to
Class Cestoda s.g. to
Class Trematoda
149
Lab examples of Class Turbellaria
Dugesia
150
Lab example of Class Cestoda
Taenia
151
Lab example of Class Trematoda
Opisthorchis sinensis
152
Platyhelminthes characteristics
```
bilaterally symmetric
dorsoventrally flattened
acoelomate
GVC (digestion + circulation)
no anus
mm's - m's
free-living/parasitic
```
153
Platyhelminthes reproduction
hermaphroditic
complex reproductive system
gametes arise from mesoderm
gametes fill space between epidermal epithelium and gastrodermal epithelium
154
Platyhelminth mesothelium gives rise to
gametes
muscle cells
parenchymal cells
155
Platyhelminthe excretion
protonephridium
156
Platyhelminthe locomotion
muscles
| ventral cilia
157
Class Turbellaria
mostly free-living
rhabdite
regenerate lost body parts
158
Class Turbellaria name meaning
whirlpool
| swirling motion of particle near ciliated epidermis
159
rhabdite (Turbellaria)
rod-like epithelium secretions
unique to Turbellaria
swells on contact w/ water, forms thick mucus
adhesion, locomotion, defensive
160
neoblasts
Turbellaria
undifferentiated pluripotent cells in parenchyma
responsible for regeneration
161
pluripotent
cells having the capability to differentiate into a large number of different cell types
'stem cells'
162
Turbellaria reproduction
asexually -budding, transverse fission
| sexually
163
Turbellaria sexual reproduction process
non-self fertilizing hermaphrodites
penis - genital pore - sperm deposited in to copulatory bursa - sperm moves up oviducts to ovaries - fertilizes egg - egg passes down oviduct - invested w/ yolk cells - discharged from yolk gland - encapsulated - passed out genital pore - fastened to objects (e.g. rocks)
164
Turbellarian post-reproduction
after breeding reproductive system degenerate and is regenerated at next sexual period
165
Important Turbellarian body parts
```
Intestinal caeca
eye spots
auricles
pharynx
pharyngeal cavity
```
166
Turbellarian guts
Syndesmis - commensal Turbellarian in echinoderm gut- simple unbranched gut cavity
Dugesia - 3 principle branches (caeca) with short side-branches
Leptoplana (marine polyclad) - many branches
167
Turbellarian feedings
largely carnivorous
mid-ventral mouth at end of protrusible pharynx
pharyngeal enzymes initiate digestion
intestinal enzymes continue digestion
168
Turbellarian excretion
ammonia diffused across body surface
| protonephridia assist excretion and osmoregulation
169
Turbellaria locomotion
much-ciliary gliding
muscular crawling
swimming
170
Class Trematoda
entirely parasitic
| 2-3 hosts
171
Opisthorchis sinensis
Oriental/Chinese liver fluke
bile ducts of humans (definitive host)
intermediate hosts - snails, fish
prevalent in Southeast Asia
172
Trematode major body parts
mouth surrounded by oral sucker
ventral sucker
excretory pore (nephridiopore)
muscular pharynx, short esophagus, 2 intestinal caeca
173
Trematode reproductive organs
```
2 multi lobed testes
seminal receptacle (sperm storage)
single ovoid ovary (ova production)
vitelline glands (yolk)
coiled uterus (filled with encapsulated, fertilized eggs)
```
174
Trematode life cycle characteristics
complex
1+ intermediate host
several larval forms that undergo asexual division
175
asexual reproduction by embryonic larval stages
polyembryony
176
Trematoda life cycle
adult in bile ducts - eggs in feces - eaten by freshwater snail - ciliated miracidium - hatches, burrows through intestinal wall - sporocyst - polyembryony - redial - polyembryony - cercariae - rupture body wall - free-swimming - burrow in to fish (carp) within 24-48hrs - encyst - metacercariae - human eat raw fish
177
Class Cestoda
tapeworms
endoparasites
specialized for life w/i host intestine
scolex, neck, proglottids (strobila)
178
Cestode specializations
no cilia
tegument
no mouth
no digestive cavity
179
tegument
syncytial epidermis specialized for direct absorption of nutrients
180
scolex
Cestoda head region
| anchor for adhering to intestine
181
Cestoda neck
generates proglottids
182
Cestoda strobila
series of proglottids
| body segments that contain full m+f reproductive organs
183
tapeworm life cycle
most have 2 hosts
adult in carnivore - gravid proglottid released in feces - encysted cysticercus in herbivore - larvae burrows in to blood vessel - carried to muscle - herbivore eaten by carnivore - scolex everts -- attaches to gut
184
Trematoda vs Cestoda attachment structures
Trematoda - 2 suckers (oral, ventral)
| Cestoda - hooks (end of scolex) + 4 suckers
185
Trematoda vs Cestoda offspring numbers
Cestoda - eggs --> 2 stages of polyembryony
| Trematoda - multiple sexual proglottids w/ many larvae each, no polyembryony
186
Turbellarian vs Cestoda epidermis
Turbellarian - ciliated, glands, rhabdite
| Cestoda - no cilia, syncytial (absorptive) - seems more 'basic' but is actually specialized
187
Should production of proglottids by cestodes be considered a form of asexual reproduction
not in species that do not self-fertilize
1 proglottid can fertilize with another proglottid on the same worm (or with a different worm) but not within that proglottid
some species can self-fertilize w/i the same proglottid
188
Phylum Rotifera
microscopic, aquatic, mostly freshwater
head, neck, trunk, foot
corona
mastax, trophi
189
corona
Rotifera crown of cilia
| swimming, feeding
190
mastax
Rotifera pharynx
| has trophi jaws to grind up food
191
Rotifer epidermis
contains thick layer cytoskeletal filaments (not moulted)
| makes outer surface rigid
192
Rotifer trunk
stomach
gonad (usually an ovary)
protonephridia
(anus at trunk/foot junction)
193
Rotifer toes
at end of foot
| contain cement gland ducts (attachment)
194
unique reproduction in Rotifers
pathogenesis
| part of their amictic/mictic life cycle
195
possible value of parthenogenesis
```
don't have to find a mate
boosts population (only produce more f's)
genetic stability
```
196
how do rotifers survive ephemeral/freezing water bodies
In mictic stage of life cycle they reproduce asexually and the fertilized eggs secretes a protective coating and enters diapause
197
Phylum Annelida phylogeny
Errantia - Neriedidae
| Sedentaria - Clitellata, Terebellidae, Echiuridae, Sabellidae, Siboglinidae
198
Errantia and Sedentaria taxa
were abandoned in 1970s
| now appear to be monophyletic, true clades
199
Phylum Annelida characteristics
extremely diverse
eucoelomate
most have metameric body
mouth and anus, unidirectional gut
200
Annelid habitat
diverse
| most marine
201
Annelid past phylogeny
thought to be closely related to arthropods (metamerism, nervous system)
3 Subclasses - Polychaeta, Oligochaeta, Hirudinea
202
molecular data
nucleotide sequences of slowly evolving nuclear and mitochondrial genes
amino acid sequences of proteins
203
major revisions of Annelid phylogeny
1. metamerism found to be convergent
2. Echiuran, Sipuncula, Pogonophora found to belong within Phylum Annelida
3. Polychaeta = paraphyletic
204
results of major revision 1. in Annelid phylogeny (metamerism convergent)
-Arthropods moved to Ecdysozoa w/ other moulters -Annelids + Mollusks placed in Lophotrochozoa
205
results of major revision 2. in Annelid phylogeny (Echiuran, Sipunculan, Pogonophora belong in Annelida)
not all Annelids display metamerism as adults
206
Echiuran metamerism
metameric ganglia along ventral nerve cord during early development
207
Sipuncula metamerism
none
208
Echiuran, Sipunculan reduced/lossed metamerism
secondary loss
209
Annelid chaetae
not present in Hirudineans, Sipunculans
| secondary loss
210
an ancestral metamere contains
```
pair of ganglia
paired peripheral nerve tracts along ventral nerve cord
paired metanephridia
blocks of circular/longitudinal muscle
segmental blood vessels
left/right eucoelomic compartments
```
211
anterior part of Annelid head
prostomium
| not a true metamere
212
posterior end of Annelid
pygidium
| not a true metamere
213
eucoelom
internal, fluid-filled compartment lined by mesoderm derived epithelium (mesothelium)
214
Annelid eucoelom
facilitates locomotion (like hs skeleton)
circulates body fluids
reproduction
excretion, osmoregulation
215
innovation of eucoelomic secondary body compartments allows
efficiency of functions -- evolution of active movement by large animals
216
Annelid movement
crawling
burrowing
tube-dwelling
swimming
217
Errantids
```
mobile - crawling/swimming
well-developed parapodia, aciculae
head appendages- sensory reception
cephalic eyes
nuchal organs
eversible pharynx w/ jaws
```
218
Sedentarids
sedentary - buried in substrate, inhabit tubes
reduced/lacking parapodia, no acicula
appendages for food capture not sensory
some eversible pharynx, no jaws
219
Sedentarids tubes
sand grains
calcium carbonate
proteinaceous secretions
220
acicula
chitinous rod
| support parapodia
221
active life style requires
capacity for sensing diverse environmental stimuli
222
nuchal organs
non-visible chemosensory structures
223
Annelid parapodia structure
upper lobe = notopodium
lower lobe = neuropodium
chitinous rods = acicula
chaetae at end of acicula
224
Nereis locomotion
Errantid - active, well-developed parapodia
parapodia on either side of metamere out of phase
propagate effective stroke down length of worm
curve body for faster movement
225
Lumbricus movement
earthworm, Sedentarid - lack parapodia
| peristaltic movements
226
why are the longitudinal muscles of Nereis much more massive than the circular muscles
longitudinal muscles for body undulations
movement is along the longitudinal axis, requiring longitudinal muscles
no peristaltic movement
227
what are longitudinal and circular muscles of earthworm developed approximately equal
peristaltic
muscles are used antagonistically for movement - balance each other out
both are used equally for movement
228
what is the role of chaetae in Nereis
traction in crawling
| surface area/paddles for swimming
229
what is the role of chaetae in Lumbricus
erect chaetae hold position in burrow (anchor)
230
what is the role of a fluid filled compartment in Nereis and Lumbricus
N - structural - supports body during movement
| L - movement - transmits force for peristaltic movement, hydrostatic skeleton
231
between metameres in Lumbricus
intersegmental septa
232
animals that lack efficient food processing and digestion
can be large but incapable of energetic locomotory movements - ambush prey, escape from predators, move from inhospitable environment
233
Active movement by a large animal requires
high metabolic rate from:
efficient food digestion
efficient nutrient/gas circulation to tissues
234
one-way gut
facilitates digestive efficiency
| -food sequentially processed by differently specialized gut regions
235
Lumbricus circulation of gases and nutrients
ciliated eucoelom
| dorsal, ventral, segmental blood vessels
236
calciferous glands
associated w/ earthworm esophagus
secrete CaCO3
pH adjustment of food? excretion?
237
typhlosole
internal fold of the earthworm intestine; increased SA for efficient digestion
238
chloragogen tissue
earthworm
glycogen & fat synthesis & storage
hemoglobin synthesis
protein catabolism & urea synthesis
239
Family Nereididae
Errantid Annelid
paired parapodia
eversible pharynx w/ jaws
sensory structures on head (prostomium + peristomium)
240
Nereididae sensory structures
```
eyes
tentacles
palms
cirri
allow monitoring of environment while foraging, avoid threats
```
241
Sedentarid Annelids
reduced parapodia
if eversible pharynx present - no jaws
appendages - feeding
suspension feeders (small particles/phytopl.) or deposit feeders (surface film)
242
Sedentarid habitat
sand/mud burrows
| tubes - sand grains, CaCO3, proteinaceous
243
selective deposit feeders
grains picked-up, inspected, selectively ingested
244
non-selective deposite feeders
bulk ingest mouthfuls of sediment indiscriminately
245
Family Terebellidae
```
spaghetti worm
tubes of sand grains
very reduced parapodia
2 types of tentacles
selective deposit feeders
```
246
Terebellidae tentacles
1.long spaghetti-like tentacles for feeding
ciliated groove down length for carrying particles via cilia+mucus
2.branchial tentacles, shorter, coiled/dendritically branched, red (hemoglobin)
247
Why do Terebellids have hemoglobin
tubes often constructed under rocks embedded in sediment - O2 partial pressure can be very low
Hemoglobin helps pull O2 into body
248
Family Sabellidae
feather duster worms
tubes
radioles
suspension feeders
249
Sabellid tube
proteinaceous secretions
| attached to solid substrate (often under docks)
250
Sabellid radioles
crown of ciliated tentacles, each w/ 2 rows of short side-branches
capture suspended phytoplankton
particle moves: down side branches - to ciliated groove on central axis - - mouth
251
Family Siboglinidae
benthic, tube-dwelling, marine
opisthosoma
trophosome
anterior branchial filaments (red, hemoglobin)
252
Siboglinid opisthosome
posterior section
only part of worm that is metameric and has chaetae
anchor worm to tube
253
Siboglinid trophosome
endodermal cells form non-structured mass rather than digestive tract
cells filled w/ chemosynthetic bacteria that provide organic carbon
254
chemosynthetic bacteria
oxidize H2S to generate E for carbon fixation
255
Siboglinid branchial filaments
contain hemoglobin
| binding sites for oxygen and sulfide
256
Oligochaete sister group
Hiurdinea
| Annelida, Sedentaria, Clitellata, Hirudinea
257
Hirudinea, Oligochaeta synapomorphies
hermaphroditic reproductive system (other annelids are dioecious)
clitellum (significance in reproduction)
258
Leeches
ectoparasites or predators
some have thickened cuticle around mouth forming 3 blades
some have eversible pharynx w secretions
2 suckers (oral, posterior)
259
Hirudinea gut
specialized to accommodate large meal (food is mostly water)
well-developed metanephridia (1 pr/metamere)
lateral diverticula = caeca (folded gut wall)
260
Hirudinea locomotion
looping
alternating contraction of circular/longitudinal muscles
body pushes/pulls against suckers
swim- sinusoidal waves of long. muscle contraction
261
Why are Hirudineans dorsoventrally flattened
flattening reduces flexual stiffness - aids in looping
262
function of parapodia in tubiculous annelids
hide from predation
move up for feeding
hold on to tube (anchor)
move around to flush-out tube
263
why do oligochaetes have pharyngeal dilator muscles
to suck-up large amounts of particles as they are non-selective; terebellids are selective and use tentacles to choose particles
264
trends in Siboglinid evolution
levels of sulfide tolerance
| type of substrate
265
basal groups of Siboglinids
Lamellibrachia
inhabit soft substrate
slightly elevated sulfide levels
266
derived groups of Siboglinids
hard substrate
high sulphide levels
elevated temperatures
