SDSU Ekdale Bio101 Test 2 #2 Spring'25 Questions With
Complete Solutions
adductor muscle Correct Answers muscles that hold the valves
in bivalvia together (it is the part of a scallop that we eat). It also
can be used to help scallops swim actively. Predatory snails will
drill through bivalvia shells to get their adductor muscle so that
the valves open more freely.
Animals that shed their outer, non-cellular layer belong to which
of the following clades? Correct Answers Ecdysozoa
Annelids have metameric segmentation. What does that mean?
Correct Answers Metameric segmentation is when the Annelid
is segmented, the body is divided into serial parts divided by
septa. These parts are the same.
Bivalve molluks have lost their radula. How do they eat?
Correct Answers They eat by using their incurrent and
excurrent siphons to move water over their gills, which filter
their food, food is then trapped in mucus that is transported to
their mouth via cilia.
blastopore Correct Answers first opening to develop in
bilaterian animals; developes into mouth in proterostomes and
anus in deuterostomes
Briefly discuss the lifestyle(s) of nematodes. Are they free-
living, symbiotic, or parasitic? Correct Answers Nematodes
can be free-living, multualistic, or parasitic. Free-living
nematodes are those like the C. elegans, a "model organism" we
,used for scientific research. It was the first multicellular
organism to have its genome sequenced. Mutualistic nematodes
live in the intestines of iguanas and help the iguanas digest plant
material. Parasitic nematodes can live in our intestines, sucking
our blood and penetrating our lungs.
carapace Correct Answers shell-like plate (calcified chitin)
covering the cepahlothorax of some crustaceans
chelicerae Correct Answers pair of head appendages on
members of Chelicerata (including arachnids)
chelipeds Correct Answers pincer-like first pair of legs in
crustaceans, used for seizing and crushing
chitin Correct Answers a hard carbohydrate. It is a tough,
resistant, nitrogenous polysasccharide that is insoluble in water,
alkalies, and weak acids.
clitellum Correct Answers secretory organ. In lumbricidae, the
clitellum secretes mucus that forms a cocoon for fertilized eggs
cniodocyte Correct Answers specialized stinging cells of
cnidarians
Compound eyes, a chitinous exoskeleton, and jointed
appendages are synapomorphies for the ? Correct Answers
Arthropoda
, Cryptobiosis, a form of biological stasis that is exhibited by
members of Tardigrada, occurs in response to? Correct Answers
adverse climatic conditions
dioecious Correct Answers male and female sex organs are
present on separate individuals
Distinguish between complete and incomplete metamorphosis in
hexapods. Correct Answers Incomplete metamorphosis is a
gradual transition from larvae to adults with an intermediate
nymph stage. In complete metamorphosis, the larva develops
dramatically within a chrysalis (pupa) before emerging as an
adult. (No nymph stage in complete metamorphosis.)
Distinguish between different myriapod clades. Correct
Answers Chilopods (centipedes) have one pair of legs per trunk
segment, whereas diplopods (millipedes) have two legs per
trunk segment.
Distinguish between the wings of Lepidoptera, Coleoptera,
Hymenoptera, and Diptera in terms of number and form. (These
are four of several major clades of hexapods.) Correct Answers
*Lepidoptera* - butterflies and moths with two pairs of large,
scale-covered wings
*Coleoptera* - beetles with two pairs of wings, forewings
covered by protective shell (elytra)
*Hymenoptera* - ants and bees with two pairs of membranous
wings
*Diptera* - true flies with one pair of wings (hindwings
modified as halteres)
Complete Solutions
adductor muscle Correct Answers muscles that hold the valves
in bivalvia together (it is the part of a scallop that we eat). It also
can be used to help scallops swim actively. Predatory snails will
drill through bivalvia shells to get their adductor muscle so that
the valves open more freely.
Animals that shed their outer, non-cellular layer belong to which
of the following clades? Correct Answers Ecdysozoa
Annelids have metameric segmentation. What does that mean?
Correct Answers Metameric segmentation is when the Annelid
is segmented, the body is divided into serial parts divided by
septa. These parts are the same.
Bivalve molluks have lost their radula. How do they eat?
Correct Answers They eat by using their incurrent and
excurrent siphons to move water over their gills, which filter
their food, food is then trapped in mucus that is transported to
their mouth via cilia.
blastopore Correct Answers first opening to develop in
bilaterian animals; developes into mouth in proterostomes and
anus in deuterostomes
Briefly discuss the lifestyle(s) of nematodes. Are they free-
living, symbiotic, or parasitic? Correct Answers Nematodes
can be free-living, multualistic, or parasitic. Free-living
nematodes are those like the C. elegans, a "model organism" we
,used for scientific research. It was the first multicellular
organism to have its genome sequenced. Mutualistic nematodes
live in the intestines of iguanas and help the iguanas digest plant
material. Parasitic nematodes can live in our intestines, sucking
our blood and penetrating our lungs.
carapace Correct Answers shell-like plate (calcified chitin)
covering the cepahlothorax of some crustaceans
chelicerae Correct Answers pair of head appendages on
members of Chelicerata (including arachnids)
chelipeds Correct Answers pincer-like first pair of legs in
crustaceans, used for seizing and crushing
chitin Correct Answers a hard carbohydrate. It is a tough,
resistant, nitrogenous polysasccharide that is insoluble in water,
alkalies, and weak acids.
clitellum Correct Answers secretory organ. In lumbricidae, the
clitellum secretes mucus that forms a cocoon for fertilized eggs
cniodocyte Correct Answers specialized stinging cells of
cnidarians
Compound eyes, a chitinous exoskeleton, and jointed
appendages are synapomorphies for the ? Correct Answers
Arthropoda
, Cryptobiosis, a form of biological stasis that is exhibited by
members of Tardigrada, occurs in response to? Correct Answers
adverse climatic conditions
dioecious Correct Answers male and female sex organs are
present on separate individuals
Distinguish between complete and incomplete metamorphosis in
hexapods. Correct Answers Incomplete metamorphosis is a
gradual transition from larvae to adults with an intermediate
nymph stage. In complete metamorphosis, the larva develops
dramatically within a chrysalis (pupa) before emerging as an
adult. (No nymph stage in complete metamorphosis.)
Distinguish between different myriapod clades. Correct
Answers Chilopods (centipedes) have one pair of legs per trunk
segment, whereas diplopods (millipedes) have two legs per
trunk segment.
Distinguish between the wings of Lepidoptera, Coleoptera,
Hymenoptera, and Diptera in terms of number and form. (These
are four of several major clades of hexapods.) Correct Answers
*Lepidoptera* - butterflies and moths with two pairs of large,
scale-covered wings
*Coleoptera* - beetles with two pairs of wings, forewings
covered by protective shell (elytra)
*Hymenoptera* - ants and bees with two pairs of membranous
wings
*Diptera* - true flies with one pair of wings (hindwings
modified as halteres)
