Biology 2 Lecture Connect HW - Ch. 34 Invertebrates
What are morphological characteristics of crustaceans?
A body plan consisting of a cephalothorax and abdomen A nauplius larval stage that differs significantly in appearance from the adult stage Two pairs of antennae
What is spongin?
A protein that lends skeletal support to sponges lacking spicules
What statements are true of members of the phylum Nematoda?
Also called round worms They undergo ecdysis Many species are parasitic
The components of the skeleton of a sponge.
Calcium carbonate spicules Spongin fibers Silica spicules
Fill in the names of the appropriate phyla for the distinguishing characteristics listed below. Phylum ______________: Diploblastic; gastrovascular cavity for extracellular digestion; radial symmetry; polyp and medusa forms; stinging cells Phylum ___________: Deuterostome development; notochord; pharyngeal slits; hollow dorsal nerve cord; muscular post-anal tail Phylum ______________: Deuterostome development; water vascular system; endoskeleton composed of ossicles; tube feet Phylum ____________: Bilateral symmetry; protostome development; body plan made up of mantle, visceral mass, and foot; some species have a shell
Cnidiaria; Chordata; Echinodermatoa; Mollusca
Nematoda
Complete gut; circulatory system absent; excretory tubules; brain and nerve cords; hydrostatic skeleton
Chordata
Complete gut; closed circulatory system; kidneys; brain and dorsal hollow nerve cord; endoskeleton of cartilage or bone
Mollusca
Complete gut; open circulatory system in most species; gills for respiration; metanephridia; ganglia with nerve cords; hydrostatic skeleton Bilateral symmetry; triploblastic; body plan comprised of a foot, visceral mass, and mantle; some species have a shell for protection
Echinodermata
Complete gut; tube feet; nerve ring and radial nerves; endoskeleton of plates beneath outer skin Larvae exhibit bilateral symmetry, adults radial; triploblastic; tube feet; deuterostome development; endoskeleton composed of ossicles
Indicate the correct arthropod subphylum containing each of the organisms listed below. Shrimp: __________ Butterflies: ___________ Scorpions: ___________ Centipedes: _____________
Crustacea; Hexapoda; Chelicerta; Myriapoda
What animal phylum includes members that are hermaphroditic, often bioluminescent, live in marine environments, and use cilia for movement?
Ctenophora
Which phylum contains members that are all hermaphrodites?
Ctenophora
The members of what echinoderm class are best described as being spherical or disc-shaped, with moveable spines but no arms, and often feed on seaweeds?
Echinoidea
Characteristics of echinoderms:
Endoskeleton composed of calcareous plates Tube feet Presence of a water vascular system
How do cnidarians use cnidocytes?
For defense To immobilize prey
What are characteristics of members of the Cnidaria phylum?
Found in marine or freshwater habitats Possess a mesoglea
Turbellaria
Free-living; often found in lakes, ponds, and marine habitats.
What statement best describes symmetry in echinoderms?
Free-swimming larvae have bilateral symmetry, while the adult form is radially symmetrical
What are the four classes of the phylum Cnidaria?
Hydrozoa, Scyphozoa, Cubozoa, Anthozoa
What statement best describes reproduction in the Platyhelminthes?
In all species, reproduction is either sexual or asexual
Trematoda
Internal parasites; complex life cycle with multiple hosts; a mollusk is often the intermediate host and the definitive host is usually a vertebrate
Cestoda
Internal parasites; often have two vertebrate host species; scolex; proglottids; absorb nutrients across the body surface
What is a true statement about the mesoglea layer in cnidarians?
It is thick in jellyfish and thin in hydra
What are characteristics of lancelets (subphylum Cephalochordata)?
Live mostly buried in the sand are filter feeders All individuals have the four distinguishing chordate characteristics
W]at are characteristics of ctenophores?
Many species are bioluminescent. They secrete a sticky substance for prey capture. They move by coordinated beating of cilia.
Sponges are best described by what statement?
Multicellular but lack true tissues
What organisms have longitudinal muscles, a pseudocoelom, and a cuticle composed primarily of collagen that they must molt as they grow?
Nematodes
Porifera
No organ systems; endoskeleton of spicules and collagen Asymmetrical; no true tissues; choanocytes move water through the body wall and trap food particles
What are defining characteristics of the phylum Chordata?
Notochord Muscular post-anal tail Hollow dorsal nerve cord Pharyngeal slits
Acoelomate organisms that have a flattened body make up the phylum:
Platyhelminthes
What organisms have a pseudocoelom and a ciliated crown?
Rotifers
What characteristics are often associated with the annelid group Errantia?
Setae supported on parapodia Brightly colored bodies Free-living predatory lifestyle
How do sponges reproduce?
Sperm are released into the water and fertilize eggs in the mesohyl of another sponge, developing into swimming larvae. A small fragment or bud may detach and form new sponge.
What are cnidocytes?
Stinging cells that can be used in defense or prey capture
What is a spongocoel?
The central cavity of a sponge
What statements about the body forms of cnidarians is TRUE?
The polyp is sessile and the medusa is motile
What is true of the phylum Chordata?
This phylum includes invertebrate organisms. This phylum includes all of the vertebrate organisms. The endoskeleton is always internal, with muscles attached.
What sentence best describes the feeding mechanism of a sponge?
Tiny food particles are trapped by flagellated cells as water is drawn through pores in the body of the sponge and exits via the osculum.
The class ______ includes the flukes.
Trematoda
True or false: Although adult sponges are sessile, larval sponges are motile.
True
True or false: Only some chordates possess all four chordate characteristics in their adult life, but all chordates exhibit these features at some time during development.
True
True or false: The chordate endoskeleton is always internal, with muscles attached.
True
An invertebrate animal is one that does not have:
a backbone
Mobile cells found in sponges that absorb food and carry nutrients to other cells are known as __________.
amoebocytes
Ophiuroidea
brittle stars Five long, slender arms; tube feet that are not used for locomotion; browse on sea bottom or filter feed
The only mollusks with a closed circulatory system are the:
cephalopods
What invertebrate organisms have a particularly important ecological role in enriching soil through their feeding and digestive processes?
earthworms
Cephalization is the process:
in platyhelminthes that produces a head that contains sensory appendages
Organs that can sense light but are not considered to be true eyes are known as ___________.
ocelli
The jointed foot of rotifers contains __________ _______________, which secrete a sticky substance that aids in attachment to the substrate.
pedal glands
What characteristic is NOT found in all mollusks?
radula
Most echinoderms undergo ________ reproduction. Fertilization is ____________, occurring in the water where gametes are released. Fertilized eggs develop into free-swimming __________, which float in the ocean until they metamorphose into adults.
sexual; external; larvae
A group of cells that have a similar structure and function is known as a _________.
tissue
What accurately describes the number of body forms exhibited by most cnidarians?
two
Identify the phylum whose members have the following characteristics: small, lophophorate colonial animals that resemble plants; individual animals live within a non-living exoskeleton known as a zoecium; often found encrusted on rocks in shallow aquatic environments.
Bryozoa
The most morphologically complex class of mollusks is ____________. Most members are fast-swimming marine predators with a series of arms and a beak-like jaw that allows them to capture and bite their prey.
Cephalopoda
The main classes within the Mollusk phylum include:
Cephalopoda Gastropoda Bivalvia Polyplacophora
What mollusks have a well-developed nervous system, brain, and sense organs, which support their active lifestyle?
Cephalopods
Which class do tapeworms belong?
Cestoda
Which phylum contains members that have only two germ layers, have eight rows of cilia for locomotion, and use two tentacles with sticky substances for capturing prey?
Ctenophora
The phyla __________ and ___________ are included in the Deuterostomia clade because their members undergo deuterostome embryonic development.
Echinodermatoa; Choradata
Three major advantages of segmentation:
Enhanced locomotion Redundancy of organs Specialization
Within the phylum Annelida, members of the group ______ are often brightly-colored predators with well-developed eyes and parapodia, whereas those in the group ______ often have reduced head appendages, live in tubes and burrows, and have setae that are close to the body wall.
Errantia; Sedentaria
Monogenea
External parasites of fish
What accurately describe reproduction in echinoderms?
Fertilization is external Most reproduction is sexual Larvae are free-swimming
What are characteristics of the phylum Ctenophora?
Gastrovascular cavity Eight rows of cilia on their surface Two long tentacles that secrete a sticky substance for prey capture
Platyhelminthes
Gastrovascular cavity, protonephridia with flame cells; cerebral ganglia with lateral nerve cords and nerve net; hydrostatic skeleton
What are the names of the five subphyla within the Arthropoda phylum?
Hexapoda Crustacea Chelicerata Trilobita Myriapoda
What are nematocysts?
Powerful stinging capsules in cnidarians with an inverted coiled and barded thread
Although they are sessile, sponges can defend themselves in which of the following ways?
Production of toxic chemicals Spicules to deter predation
Distinguishing characteristics of the Lophotrochozoa clade:
Protostome development A lophophore or a distinct trochophore larval stage
Cnidaria
Radial symmetry; diploblastic; polyp and medusa forms; stinging cells
What is true of decapods?
Ten walking legs, one pair of which is often modified into large claws They include the largest crustacean species
Members of the phylum Platyhelminthes have what characteristics?
They are acoelomate. They have mesoderm. They exhibit cephalization.
What statements accurately describe organisms in the mollusk class Gastropoda?
They are found in marine, freshwater, and terrestrial environments. They use a radula for feeding.
Characteristics of members of the phylum Bryozoa:
They are often found encrusting rocks in shallow aquatic environments. They possess a lophophore. Each animal secretes and lives inside a zoecium composed of chitin or calcium carbonate.
What are characteristics of crustaceans?
They can be predators, scavengers, or filter feeders Some larger species are economically important food sources for humans. They have a nauplius larval form that differs significantly in appearance from the adult form Eggs are carried in pouches under the mother's body
What class comprises the only free-living class of flatworms?
Turberllia
Features of the nematode body plan include:
a pseudocoelom that acts as a circulatory system and fluid-filled skeleton longitudinal musculature a mouth with stylets
In Platyhelminthes, reproduction may occur:
asexually by splitting into two, and each half regenerates the missing half. sexually; hermaphroditic individuals fertilize the eggs of one another
What substances make up the exoskeleton of an arthropod?
chitin and protein
Sponges have flagellated cells that line the spongocoel, help water flow through the pores, and trap food particles. These cells are known as ___________.
choanocytes
Ctenophores use _________ to propel themselves in the water column.
cilia
Members of the phylum Rotifera get their name from their __________ which have a known as a corona that is used in locomotion and feeding?
ciliated crown
What organisms are members of the Mollusca phylum?
clams snails chiton
The hairlike trigger on the surface of a cnidocyte is called the .
cnidocil
In cnidarians, each cnidocyte has a hairlike trigger called a ______ on its surface. When it is stimulated, it can lead to the discharge of the ______, which is used in defense or capture of prey.
cnidocil; nematocyst
Cnidarians have stinging cells called ___________ which contain powerful capsules called nematocysts. These are used in prey capture and defense.
cnidocytes
Which group of animals were the first to possess a gastrovascular cavity for digestion and anal pores to eliminate wastes?
comb jellies
In ctenophores, digestion occurs in a(n) ________ cavity, and waste and water are eliminated through two anal pores.
gastrovascular
Earthworms ingest soil and leaf tissue to extract nutrients. As this material passes through the earthworm's digestive system, it is finely ground into smaller fragments in the ___________. Once excreted, this material, called ____________, enriches the soil.
gizzard; casting
In animals, about 95% of all species are
invertebrates
The mesoglea in ______ is enlarged and forms a transparent jelly.
jellyfish
Bioluminescence is a phenomenon that causes an organism to produce:
light
Statocysts are organs that:
maintain balance and equilibrium
Three main parts of a mollusk's body plan:
mantle foot visceral mass
Cnidarians possess a gelatinous substance called the _________, which connects the endoderm and ectoderm.
mesoglea
The gelatinous matrix that is found between the choanocyte and epithelial cell layers of a sponge is known as the ____________.
mesophyl
Most cnidarians exist as two different body forms: the _________ and the __________.
polyp; medusa
Holothuroidea
sea cucumbers Elongated body; no arms or spines; reduced endoskeleton; tube feet; browse on sea bottom
Crinoidea
sea lilies and feather stars Cup-shaped; often attached to substrate via stalk; arms used in filter feeding
Asteroidea
sea stars Five arms; tube feet; predatory on bivalves and other echinoderms; reversible stomach
Echinoidea
sea urchins and sand dollars Spherical or disc-shaped; no arms; tube feed and moveable spines; pedicellariae; many feed on seaweeds
The phylum Annelida consists of the _______ worms.
segmented
Features of the arthropod body plan include:
segments fused into tagmata jointed appendages compound eyes composed of ommatidia a cuticle composed of chitin and protein
What best describes adult sponges?
sessile
Mollusks have a soft body, which may be covered by a tough external __________. Their basic body plan consists of three parts: a muscular _________(used for movement), a(n) ________ mass (which contains the internal organs), and a(n) __________(which produces the shell in mollusks that have one).
shell; foot; visceral; mantle
The foot of some cephalopods has become modified into a muscular ___________, which allows movement that is similar to jet propulsion.
siphon
In sponges, some amoebocyte cells can form a tough skeletal fibers that support the body. This skeleton consists of sharp structures formed of protein, calcium carbonate, or silica, called ____________.
spicules
What organisms make up the Porifera phylum?
sponges
The feeding mechanism of a sponge can be summarized as such: Water is drawn into the ______ by the beating action of ________. Small particulate matter and tiny plankton are trapped and eaten, while the water then flows out through the large opening at the top.
spongocoel; choanocytes
Members of what phylum can be described as such: segmented organisms that have a complete digestive system, a ventral nerve cord, and a coelom that acts as a hydrostatic skeleton?
Annelida
Segmented organisms with jointed legs and a hard exoskeleton composed of chitin make up the phylum __________.
Anthropoda
Anthropoda
Bilateral symmetry; triploblastic; segmented; a hard cuticle composed primarily of chitin; ecdysis Complete gut; open circulatory system; excretory glands; brain with ventral nerve cord; exoskeleton
Map the path of water through the water vascular system of echinoderms with the part of the body where water enters at the top.
Madreporite Ring Canel Five Radial Canels Tube Feet