Unit 1 Exam
Class Scaphopoda
- tusk shells - have tubular shell - buries head end in sand, cycles water past mantle for respiration
Torsion
- twisting of body plan during development distorts bilateral symmetry - anus and mantle cavity swing around to be anterior
Caudofoveata
- very ancestral - worm-like burrowers. Feed off of organic material in soil
Solenogastres
- worm-like bottom dwellers - no radula. lost gills use mantle, reduced shell
What are the levels of organization?
1. Protoplasmic grade 2. Cellular Grade 3. Cell-tissue grade 4. Tissue-organ grade 5. Organ-system grade
How many marine species and freshwater species are there of Porifera
8600 marine species 150 freshwater species
Torsion is a two-step process where the shell and enclosed viscera rotate ______ degrees counterclockwise relative to the head
90
How many species are there
90,000
characteristics of members of class Scyphozoa
: A scalloped bell margin, with the number of notches ranging from 4 to 16, A medusa bell that typically ranges from 2 to 40 cm in diameter, Lappets and rhopalia occurring at marginal notches
What is a hypostome?
A conical protuberance upon which the mouth is situated, found in hydras
Cnidoblast
A developing cnidocyte
characteristics of a typical cnidarian polyp
A gastrovascular cavity, Attachment to the substratum by a pedal disc or similar structure, Asexual reproduction through budding, fission, or pedal laceration, A mouth surrounded by tentacles at the oral end of the body
Fission :
A polyp divides in half and one side of the polyp pulls away from the other side
Cnidocil
A triggerlike structure that causes the specialized organelles of cnidocytes to discharge
What kind of habitats do they live in
Adaptive radiation - live in a variety of habitats marine, freshwater, terrestrial (snails)
Which schistosome individual is broader and heavier?
Adult male
Which of the following statements are true about sponges?
Adult sponges do not have distinct cell layers, Sponges are not diploblastic.
Epitheliomuscular cells:
Allowing the body to contract and expand, similarly to true muscular cells
Are Cnidarias and ctenophoras sister taxa?
Although cnidarians and ctenophorans share many ancestral traits, they are probably not sister taxa.
Which of the following can be found in the mesohyl of sponges?
Ameboid cells
The term metazoan would be used to describe which type of organism?
Animal
truly segmented phyla include which of the following?
Annelida, Arthropoda, Chordata
Examples of Plesimorphies
Being multicellular, mitochondria
What kind of symmetry
Bilateral symmetry - well developed nervous system in some
What are the three types of asexual reproduction?
Budding, Fragmentation/Regeneration, Gemmules
Nemertea: Proboscis?
Long tongue inverts out to catch prey, housed in the body. Separate hole from mouth. Feed on annelides. Some have a hook on the end to stab prey.
What are the 5 types of connective tissue?
Loose connective tissue, Dense (fibrous) connective tissue, blood, cartilage, bone.
Phylum Mollusca are the
Lophotrochozoan Protostome
characteristics of members of class Anthozoa
Many forms produce a skeleton for support., They can be solitary or colonial., The gastrovascular cavity is partitioned by septa.
What are tracts used for
Many use tracts of cilia for feeding or locomotion (cilia helps move through muscus or feeding)
What type of platyhelminthes have a reduced or absent osmoregulatory system?
Marine turbellarians.
Leuconoid
Masses with numerous oscula and flagellated chambers filled form incurrent canals and discharge into excurrent canals
If the sponge has spicules that are straight or with 3 or 4 rays that typically surround the osculum, it is in the Class
Calcarea
What are examples materials of Sclerocytes
Calcium carbonate, silica(deposited in extracellular matrix)
What are examples materials of mineral spicules
Calcium carbonate, silica(deposited in extracellular matrix)
When was the first good fossil record for sponges seen?
Cambrian 500 mya
organisms that belong to Class Gastropoda
Conchs, Slugs, Snails, Limpets
The nervous system of a planarian (a turbellarian) consists of which of the following?
Connecting nerves, Longitudinal nerve cords, Mass of ganglion cells
What is the dermis made of?
Connective and adipose
What are the three primary germ layers (tissues) in developing embryos of animals
Ectoderm, Mesoderm, Endoderm
A flatworm egg is said to be ______________ if yolk is contained within an egg, as it is other animal phyla
Ectolecithal
What life stage of the blood fluke causes the main problems in the human host?
Eggs
Parts of cartilage
Matrix is rubbery, Chondrocyte inside lacuna, not a lot of blood flow so slow healing.
Examples of Extracellular structural components
Matrix of connective tissues (cartilage, bone) Cuticle (outer covering of insects)
Cnidaria: What layer comes from the ectoderm?
Epidermis
What are the types of tissue the skin has?
Epithelial, connective, muscle, nerves
What are the four types of tissue?
Epithelium, Connective, Muscular, Nervous
Examples of analogy
Ex. Bats and birds. Bats are mammals while birds come from reptiles. They have no recent common ancestor.
Parts of a cestode include which of the following?
Mature proglottids, Germinative zone, Gravid proglottids (expel eggs or detach), Scolex
Trematode
Excretory bladder leads to terminal pore
Waste removal from the body is handled by a/an ____________ system, while __________ systems control water balance
Excretory, osmoregulatory
True or false: True segmentation is an accepted feature of the cestodes
False
True or false: Gastropods all have similar feeding habits
False, Gastropod feeding habits are as varied as their shapes and habitats.
Filter Feeders
Feed on suspended particles in water. Phagocyte by choanocyte
Freshwater clams exhibit internal fertilization while most bivalves exhibit external fertilization discharging _________ via excurrent flow
Gametes
Cnidaria: What layer comes from the endoderm?
Gastrodermis
Snails, slugs, and limpets are examples of molluscs in the class ____________
Gastropoda
With over 70,000 living species, the Class ____________ is the largest class of molluscs
Gastropoda
Genus
Genus name is shared among closely related species
The mollusc ctenidia is also known as ______
Gills
What structures in bivalves have cilia that direct water to flow over the gills?
Gills
Intermediate Host
Growth out of a snail.
Many gastropods that are ______ use their rasping tongue to scape algae from hard surfaces
Herbivores
Six-rayed siliceous spicules are characteristic of the class
Hexactinellida
Examples of homology
Human, bat, porpoise, horse, frog
Class Hydrozoa
Hydra (freshwater, solitary), Typically marine and colonial
In hydrozoans, what feature lends support to the body and allows longitudinal extension of the body and tentacles?
Hydrostatic skeleton
What are the three types of support systems?
Hydrostatic skeleton, Exoskeleton, Endoskeleton
In hydrozoans, support and longitudinal extension of the body are achieved through the _____________ skeleton, created when the beating of cilia on the nutritive-muscular cells brings water into the ______________ cavity
Hydrostatic, gastrovascular
What cnidarian class is characterized by an asexual polyp stage with a sexual medusa stage, and often occurs in marine habitats and in a colonial form?
Hydrozoa
In hydras, the mouth is located on a conical protuberance called the _______
Hypostome
What animals fall under Phylum Cnidaria?
Hyrda, Corals, Sea Anemones
Are Animals in a taxonomic groups more closely related to each other or to species in other groups
In taxonomic groups
Lophotrochozoa
(1) the presence of a horseshoeshaped crown of ciliated tentacles (lophophores), and (2) a minute, translucent top-shaped ciliated larvae (trochophores).
Class Cephalopoda
(squid, octopuses, cuttlefishes) All marine predators with highly developed nervous systems
Colonial forms may show dimorphism in polyps
, Gonangium - reproductive, Hydranth - feeding, GVC's are connected, Polyp form dominates lifecycle
Hectocotylus
, a specialized tentacle transfers a spermatophore to the mantle cavity of the female.
What is the assumption of the typological species concept?
It is under the assumption that species aren't changing all the time
members of Phylum Cnidaria
Jellyfishes, Sea whips, Sea anemones, Corals
Class Scyphozoa
Jellyfishes, Tentacles are lined with cnidocytes and are used to capture prey, Swim by rhythmic pulsation of bell, Medusa form dominates life cycle
Polyplacophora
- Chitons - body covered by multiple plates - can be large (30cm)
What language is scientific names recorded in and why?
Latin. Because it is a dead language and can be used universally
features of the trematodes
Leaflike shape, Suckers, Adaptations for parasitism
describe members of the Class Demospongiae
Leuconoid canal system Siliceous spicules Marine and freshwater forms
What kind of system did Linnaeus devise?
Linnaeus devised a Hierarchical system with 7 (now 8) taxonomic levels
Radial Symmetry
More than two planes passing through the center of the body through the main axis produces two identical halves - Adaptive for sessile animals. Phyla Cnidaria
Domain
Most inclusive taxon - all living things are divided into 3 domains
Where is the mouth and pharynx?
Mouth on underside, extend out of the pharynx
Characteristics of Kingdom Animalia
Multicellular, Heterotrophic, Eukaryotes
Example of Cellular grade
Multicellular: Phylum Porifera
What is the arrector pili muscle made of (make hair stand up)?
Muscle tissue
What features are distinctly present in cestodes?
Muscles, Nervous system, Sensory endings in the tegument, Excretory system
In bivalves, a _________ _______ is attached to the __________ mass, which is suspended from the dorsal midline
Muscular, foot, visceral
Schwann Cells
Myelin sheath, action potential jumping, increase speed
Describe the characteristic of scientific names
Names are latin Always underlined or in italics Genus - 1st letter is capitalized, noun Species - all letters are lowercase, adjective
examples of cephalopods
Nautilus, Octopus, Squid
Cnidocytes contain what organelle?
Nematocyst
Planarian
Nephridiopore
Cnidaria: What type of nervous system do they have?
Nerve net, no cephalization
describe the life cycle of a typical colonial hydrozoan
New feeding polyps are produced through the process of budding, The zygote develops into a free-swimming planula larva.
Acoelomate
No coelom ( no body cavity) all mesodermal tissue
Larval stage
No free-living larval stage.
What is asexual reproduction?
No gamete mixing
Nemertea: Simple circulatory system?
No heart, deliver nutrients and oxygen and get rid of waste products. Blood vessels of the worm.
Smooth muscle (also called non-striated or involuntary muscle)
No striations, uninucleate, Encircle blood vessels, the intestine and other ducts. Vessels and ducts regulate fluid flow.
Does cnidaria colonies have separate Gastrovascular cavities?
No they have a common gastrovascular cavity.
Eukaryote
Nuclear membrane, mitochondria
What happens to the prey after the gastrovascular cavity?
Nutrients and small food particles are then taken in by the gastrodermis and undigested material is egested through the mouth/anus.
Respiration
- aquatic gastropods have gills or mantle. Lungs (pulmonates)- modified mantle - cavity opens to outside through pneumostome. can change the volume of the lung through mantle contraction
Monoplacophora
- body covered by a single plate, pseudometamerism (looks like metamerism (segements) but not)
Locomotion
- cephalopods move by using the mantle cavity to form a water jet. Octopuses usually walk
Class Bivalvia
- clams, mussels, oysters has two shells, no radula, little cephalization
Camoflage
- octopuses can change their color and shape. Chromatophores
Communication
- octopuses used movements of the arms and color change to communicate
Cone snails
- radula modified into poisonous harpoon used to spear, subdue prey. inject toxin and quickly paralyzes it, brings the entire animal in mouth and eats it whole.
Simple squamous epithelial
aveoli of the lungs
Dorsal
back side of animal
Ventral
belly side of animal
Turbellaria: Movement
bilateral symmetry cilia and muscular undulation
When metacercariae of the liver fluke Clonorchis are eaten in raw fish, the juveniles will migrate to the ______ and may survive there for 15 to 30 years
bile passages
Deuterostome
blastopore becomes anus
Protostome
blastopore becomes mouth
Schistosomiasis is an infection with a
blood fluke.
Schistosoma
blood fluke/trematoda, 200 million people effected, Africa, south america, asia, veins of liver (portal system)
closed circulatory system
blood is always inside of a vessel.
open circulatory system
blood is released from vessels into the interstitial spaces and slowly flows back to the heart
Circulatory system
blood transports gases and nutrients throughout body
Segmentation (Metamerism)
body is composed of repeated units called metameres or somites.
What are the types of asexual reproduction?
budding, fragmentation/ regeneration, pedal laceration, gonangium (release medusa)
Juvenile cestodes reproduce asexually through
budding.
A tubular or vase-shaped sponge with spicules composed of calcium carbonate is a
calcareous sponge
Class Calcarea
calcium carbonate spicules. CaCO3
How does a cestode reproduce?
can cross fertile (with another), or self fertilize.
Leuconoid
choanocytes line chambers scattered throughout body. No (or greatly reduced) spongocoel. Scattered chambers, increase surface area. Most efficient. Large.
A colonial aquatic eukaryote characterized by a flagellum surrounded by a collar of microvilli best describes the
choanoflagellates
Although digestion in hydras is mostly extracellular, food particles can be drawn into what type of gastrodermal cells for intracellular digestion?
Nutritive-muscular cells
_____ are light-sensitive eyespots common in turbellarians, monogeneans, and larval trematodes
Ocelli
Although ______ can move by spurting jets of water through their funnel, they are better adapted to crawling over rocks and coral using their arms
Octopuses
Epidermis
Outer layer of skin. Stratified squamous epithelial
Budding
Outgrowth, will break up and make new hydra.
members of the mollusc class Bivalvia
Oysters, Scallops, Mussels, Clams
_______ includes only some, but not all of the descendants and the most recent common ancestor.
Paraphyletic
Class Trematoda
Parasitic flukes, anterior suckers, incomplete digestive tract present, often have vertebrate host/ mollusc intermediate host
What structure in tubellarians can be simple, folded, or bulbous?
Pharynx
What phyla is Segmentation (Metamerism) found in?
Phyla Annelida, Arthropoda, and Chordata
Example of Organ-system grade
Phyla Nematoda through Chordata
Within certain cnidarian colonies, a polyp may be able to reproduce asexually to form new individuals with different morphologies, Such colonies are _______
Polymorphic
Unlike the medusa form, a typical cnidarian ___________________ has a body that is tubular in shape with a mouth surrounded by tentacles and a pedal disc or similar structure at the aboral end
Polyp
What are two basic patterns of development?
Protostome, Deuterostome
Pinacocyte Function
Provide outer covering
The subclass ________ includes most terrestrial and freshwater snails and slugs
Pulmonata
Gastropods called ______ usually lack gills, but a vascularized mantle wall has become a lung
Pulmonates
What kind of symmetry does Cnidaria Have?
Radial Symmetry
The class Solenogastres is similar to the class Caudofoveata except that they usually lack _______ and ________
Radula, gills
Sensory cells:
Recepting chemical and tactile stimuli and transferring that information to nerve cells
In cephalopods, the ink sac directly empties into the ______, which can then release ink to confuse an enemy,
Rectum
Systematics
a field of Biology concerned with classifying organisms based on evolutionary relationships
Examples of variations in the typical cnidarian life cycle (sessile polyp, free-swimming medusa) include:
a missing medusa stage in anthozoans., a floating colony of polyps in some hydrozoans., a missing medusa stage in Hydra.
What kind of body cavity do they have
Reduced coelom: eucoelomate body cavity (true coelm)
Reduced digestive system:
Rely on the host, no need for digestive tract because already digested
Fossils
Reminants of life
Gland cells:
Secreting substances that aid in flotation and attachment to surfaces
Collencyte Function
Secretion of collagen
What are the three types of neurons?
Sensory neuron, interneuron, motor neuron.
Put the life stages of a typical digenean in order, beginning at the top with the shelled embryo stage
Shelled embryo, miracidium, sporocyst, redia, cercaria, metacercaria.
Lateral
Sides of body
Class Hexactinellida
Silica Spicules, in the deep ocean, glass
characteristics of an asconoid sponge
Simple choanocyte layer lining the spongoecoel, Slender individuals attached to a common stolon, Small and tube-shaped
What are the three types of muscle?
Skeletal muscle, cardiac muscle, smooth muscle
What are Phylum Placozoa characteristics?
Small 2-3mm Body arranged in 2 cell layers Reproduce both asexually and sexually May be related to the diploblastic (containing 2 primary tissue types)
The class ___________ is a small group of bottom-dwelling marine organisms that usually lack radula and gills
Solenogastres
Most bivalves have a unique developmental stage called a _______ which is a juvenile shelled form
Spat
What kind of respiratory organs
Special respiratory organs - lungs and gills
Cell-tissue grade
Specialized cells are organized to perform a specific function. Body is made up of tissues
describe members of the Class Calcarea
Spicules of calcium carbonate All canal types represented
What is the protein fibers in the extracellular material?
Spongin
What is the protein fibers in the mesohyl?
Spongin
Sporocytes in a typical digenean life cycle reproduce asexually to form either_________ or _______________
Sporocysts, redia
What are the three shapes of epithelium?
Squamous, cubodial, columnar
In bivalves, what organ contains a rotating crystalline rod that keeps food whirling and releases enzymes?
Stomach
Analogy
Structures that appear similar but have different evolutionary origins
Taxonomy
Study of the principles of classification, the systematic ordering and naming of organisms
male reproductive organs in order, from the site of gamete production to the point where the gametes exit the body
Testes, Vasa efferentia, vas deferens, Seminal Vesicle, copulatory organ
Axon
The electrical impulse travels down the axon to synaptic terminals where the signal is passed to the next neuron.
Cope's Law
There is a general tendency for body size to increase in a lineage overtime
describe archaeocytes
They are ameboid cells They are phagocytes They differentiate into more specialized cells.
What are typical characteristics of flatworm sexual reproduction?
They are monoecious individuals, Eggs are fertilized by a different individual (cross-fertilization).
How do flatworms increase their offspring production?
They fertilize another worm's eggs while allowing that worm to fertilize their eggs.
Until recently, the Homoscleromorphs were placed within the Class Demospongiae. What characteristic listed below required scientists to place them in their own class?
They have a true basement membrane
features that sponges share with other animals
They have same cell-signaling proteins as other animals They have a blastula stage during development.
describe choanocytes
They maintain a current of water through the canals of the sponge They are flagellated collar cells They can trap and phagocytize food particles
How do cestodes digest their food?
They rely on their host.
characteristics of sea anemones
They use pedal discs to attach to submerged objects. A structure called a siphonoglyph draws water into the animal through the movement of cilia. They are relatively large polyps, especially compared to those of hydrozoans.
True or false: While they have well-developed eyes, most cephalopods are color-blind
True
True or false: Direction of gastropod shell coiling is genetically controlled and dextral shells are far more common
True. Dexal is right side.
Triploblastic
True: Endoderm, Mesoderm (muscle) and Ectoderm
There are ______ living species in the phylum Mollusca
about 90,000
Trematoda: Definitive host is?
Vertebrate
Molluscs in the class Scaphopoda have a mantle that wraps around the _______ and fused to form a tube
Viscera
Contractile proteins
actin and myosin
what makes the patterning
actin and myosin
Protoplasmic grade
all functions necessary for life are carried out in each individual cell. Simplistic
Lophotrochozoan
also platyhelminthes. Has lophophore (feeding structure) or trochophore larva.
Phylogenetic Systematics (cladistics)
an approach to systematics that uses derived traits to produce phylogenies (evolutionary histories) of group
Spherical Symmetry
any plane passing through the center of the body produces two identical halves - Protists
Food engulfed by cells is passed to _____ for intracellular digestion occur in sponges
archaeocytes
Sponge cells that can phagocytize food particles and differentiate into other cell types like spongocytes are called
archaeocytes
Gemmules
are surrounded by spongin., are an adaptation to harsh conditions., remain dormant for extended periods
Organ systems of cephalopods
are well-developed.
Extracellular space
area not within the cells of an organism but inside the body
Intracellular space
area within the cells of an organism- cytoplasm and nucleus.
Symmetry
arrangement of body parts to the central axis of the body.
A small, tube shaped sponge with a single osculum, and the simplest organization is a(n)
asconoid sponge
The ______ body type is the simplest of sponge body forms. The ____ body type has choanocytes that line canals throughout the sponge body
asconoid; syconoid
How does the phylum Placozoa reproduce?
asexually and sexually
Cephalopods have a(n) ______ circulatory system and branchial ______ that increase blood pressure in the gills, which occur at the end of the molluscan circulatory system
closed; hearts
Cnidocytes produce one of twenty different types of organelles called __________, one of which is a nematocyst
cnida
The most primitive flatworm nervous system most closely resembles a
cnidarian nerve net.
Phylum Ctenophora
comb jellies, all marine, less than 150 species, 8 rows of cilia parallel to main body axis, tissue level of organization, bioluminescence
Endoderm
composes the digestive tract
In platyhelminthes with a digestive system, food is digested ______, and undigested food is egested through the ______
extracellularly and intracellularly; pharynx
Ancestral cephalopods shells
had straight shell which have been lost (octopi) or coiled (Nautilus - have a shell that has gas/water chambers to help with bouyancy). Squid only have a thin remnant of the shell
What is the Body composed of
head (mouth), foot(locomotion & increase inside), mantle (and associated shell), visceral mass(internal organs, digestive tract, cardiovascular, gonads)
Why is multicellular better than unicellular?
increase in the SA : V ratio. Helps metabolism grow
In syconoid sponges, water moves in through the ______ and out through the ______
incurrent canals; osculum
What happens when the cnidocyte is triggered?
injects neurotoxin into prey.
Trematodes undergo asexual reproduction in their
intermediate host
Simple columnar epithelial
intestine ( small intestine) microvilli to speed up absorption.
Digestion in sponges takes place within individual cells rather than in a cavity. This type of digestion is referred to as
intracellular digestion
Cardiac muscle
involuntary, uninucleated, striated muscle found only in the heart of vertebrates. , Branched, Intercalated discs, pacemaker
In sponges, the pinacoderm
is a layer of cells containing incurrent pores.
Fragmentation
is a type of asexual reproduction in sponges
Cephalopod eye
is not homologous with vertebrate eye but is remarkable similarity - neural connections .has lens, retina, optic nerve like humans but their neural connections are different, we have a blind spot. ours is over the retina while their is connected to the back of the retina.
Skeletal muscle (also called striated or voluntary muscle)
long, tapered multinucleated cells ,Multinucleated, Striated
Cnidaria: What kind of musculature?
longitudinal and circular
Mesohyl in sponges can be described as
loosely arranged cells and skeletal elements in a gelatinous matrix.
The pneumostome is an external opening of the ______ in pulmonate gastropods
lung
osmoregulation:
maintains water balance
sexual reproduction
male and female medusa produce egg and sperm, zygote settles to substrate and forms a polyp.
In general, cephalopods move by forcefully expelling water from the _______ through the siphon
mantle cavity
Extracellular structural components
materials produced by cells and secreted into interstitial spaces (mesohyl, sponge)
The gelatinous, jelly-like layer that lies between the epidermis and gastrodermis in cnidarians is called _________
mesoglea
The microvili-like projections on the tegument of a cestode are called
microtriches
What is the tegument like on a cestode?
microvilli, microtriches
Medial
midline of body
Medusa
mobile, body plan with tentacles on bottom. Free floating, muscle cells to pulsate the bells to swim a little.
Trematoda: Intermediate host is?
mollusc
Some flatworms have sensory, motor, and association
neurons
The shell of cephalopods provides __________ buoyancy
neutral
Acoelomate body plan
no body cavity
Neuroglia
non-nervous cells that support the nerve cells. Glia cells provide substances needed by the neurons. schwann cells.
Is the Portuguese Man-of-War a jelly fish?
not a jellyfish
The single, unique feature that is shared by all members of the Phylum Platyhelminthes is
not present--there is no such feature.
The life stage of the beef tapeworm that is swallowed by a cow is the
oncosphere.
The branches of the planarian intestine include
one anterior branch and two posterior branches.
Mollusca is ______ animal phyla
one of the largest
incomplete digestive tract
one opening serves as mouth and anus
bilateral symmetry
only one plane along the main axis produces two identical halves - adaptive for motile animals, ex. lady bug
Osculum
opening for outflow of water
Ostium
opening in side for inflow of water. Thousands of pores to let water in
Turbellaria: Cephalization/ Sensory receptors
organs that collect information about the environment
The ____ is the opening through which water is able to exit the sponge.
osculum
Definitive host
parasite can reproduce gamete
Freshwater turbellarians can reproduce asexually by constricting behind the __________ and splitting in two
pharynx
Coral bleaching
pigments or zooxanthellae are lost from animals so they appear white. due to global warming, the water gets to warm the zooxanthellae dies or gets kicked out.
The ______ are cells that form an epithelial-like outer covering of the sponge.:
pinacocytes, pinacocyte, or pinacoderm
The _________ is the outer layer of cells of a sponge.
pinacoderm
Small, platelike marine organisms that lack symmetry and organs are placed in the Phylum
placozoa
The ancestral form of gastropod shell coiling is the ______ shell, where the whorls stay in a single plane
planospiral
Pinacocytes
plate-like cells that cover the outer surface of that sponge. The outside
The "lung" in pulmonate gastropods opens to the outside by a small opening called the
pneumostome.
If a cnidarian colony is _________________, it is made up of polyps with a number of different morphologies
polymorphism
Stony Corals
polyps are embedded in a calcium carbonate substrate that they secrete as they grow. Create large coral reefs for protection.
Taenia solium
pork tapeworm. juveniles (cysticerci) can encyst in human muscle and nervous tissue. can cause cysts in the brain.
Which cells form the ostia (pores)?
porocytes
In a syconoid sponge, small lateral openings called ______ let water into the radial canals from the incurrent canals
prosopyles
The difference between thecate and athecate hydroid polyp forms is the presence of a:
protective cup formed by an extension of the perisarc.
In flatworms, excretion and osmoregulation can be handled by
protonephridia
Pseudocoelomate body plan
pseudocoelom is between the endoderm and the mesoderm. Looks like a coelom but there is no coelom. EX. nematode
The _______ is a rasping, protrusible, tongue-like organ that is found in almost all molluscs except bivalves
radula
The radula is a ______ tongue-like organ with rows of chitinous ______
rasping; teeth
Adaptations for parasitism:
reduced digestive system, Tough outer overing - tegument, Monoecious - large gonads
Pectoral
region near the forelimbs
Pelvic
region near the hindlimbs
The trochophore larvae of mollusca indicate
relatedness with many other protostome Phyla. Rotifers, Annelids, Gastrotrichs
Excretion
release of nitrogenous waste
Egestion
removal of undigested food (feces) from the body
Excretory system
removes nitrogenous waste and maintains water balance (osmoregulation) in body
In molluscs, the mantle creates a space between itself and the visceral mass which houses the ______ organs
respiratory
The mollusc ctenidium is an organ than provides __________ function
respiratory
Support System
retains the shape of the body, holds body off the ground.
Protective cells that can swell and form a protective sheath around a turbellarian are called
rhabdites.
Flatworm protonephridia
run the length of the tubellarian.
Spongocytes
secrete spongin
Are Porifera sessile or motile?
sessile
Larvae swim until they find a substrate they become ___________
sessile
Polyp
sessile body plan with tentacles (oral surface) on top, attached to substrate with aboral surface.
How do sponges reproduce?
sexually and asexually
Epithelium
sheets of cells that cover an internal or external surface. Categories are based on shape and layering
The valves, or ______, of bivalves are drawn together by adductor muscles
shells
What are the two types of layering?
simple and stratified, transitional stratified
How big is the Phylum Placozoa?
small 2-3mm
Horses millions of years ago
smaller, different feet and teeth. Feet: used to have 3 digits, now they only have 1 Teeth: they used to eat Bushes and trees, not they eat grass.
Fragmentation/Regeneration
somatic embryogenesis single parent breaks into parts that regenerate into new individuals
Extracellular digestion
specialized cells in gastrodermis secrete digestive enzymes that break apart prey organisms
What are the three types of symmetry?
spherical, radial, bilateral
describe Class Hexactinellida
spicules made of silica cylindrical or funnel-shaped body found only in marine habitats
Class Demospongiae
spicules of silica (if present) Spongin - extracellular matrix
The ________ is the same as the central cavity of the sponge.
spongocoel
Cuboidal
square shaped
In cephalopods called ______, the shell has been lost leaving only a thin, proteinaceous strip called a pen
squids
What is the epidermis made of?
stratified squamous epithelial
Homology
structural similarity that stems from having a common ancestor
Organs
structure composed of more than one type of tissue
The _______ nerve plexus is the most primitive flatworm nervous system
subepidermal
The scolex of a pork tapeworm has
suckers and hooks.
exoskeleton
support structures cover soft tissue
endoskeleton
support structures inside soft tissues
Zooxanthellae
symbiotic dinoflagellates that live in the tissue of certain Cnidaria (especially stone corals), Fix carbond, provide nutrients, remove/recycle waste. Photosynthetic.
End of dendrites
synaptic terminals, to release neurotransmitter
Classification
system of grouping things based on some type of characteristic
Class Cestoda
tapeworms, endoparasites, Scolex and proglottids, no digestive tract(microtriches on tegument to increase absoption), hooks and suckers. Latch on to upper intestine. Cannot complete life cycle without a host.
Tough outer covering:
tegument, protective layer from the host - absorb through tegument
Most bivalves are __________
filter feeders
Gills are used for
gas exchange and feeding. secrete mucus and trap food particles.
Protostome
gastrulation of blastophore into the mouth.
Mesohyl
gelatinous matrix containing spicules and protein fibers(spongin)
Asexual reproduction in sponges can occur by the formation of external buds or by the formation of internal buds called
gemmules or gemmulation
What are the parts of scientific names?
genus (noun) and specific epithet (adjective)
Connective tissue
gives support or protection, Cells and associated extracellular materials, extracellular fibers (mainly collagen), ground substace (matrix)
Eucoelomate body plan
the coelomm is completely surrounded by mesoderm. True coelom (filled). Annelides.
Captured prey are ingested into what?
the gastrovascular cavity
Anterior
the head end of the animal
In bivalves, the umbo is
the oldest part of the shell.
Cephalization
the process by which specialization becomes localized in the head end of animals.
Posterior
the tail end of the animal
Stratified
there are many layers of cells, multiple layers on top of each other
Dendrites of a neuron
they receive stimuli from receptors or other neurons.
Simple
tissue composed of a single layer of cells
bissel threads
to attach to substrate in fast flowing water
In gastropods, during the veliger stage the relative positions of the shell, digestive tract, anus and mantle cavity all change in a process called ______
torsion
The syncytial layer of the hexactinellid sponges is called the
trabecular reticulum
complete digestive tract
two openings (mouth and anus) allows for specialization
Class Turbellaria
usually free-living, dorso-ventrally flattened body, Cephalization, bilateral symmetry cilia and muscular undulation
Ontogenetic torsion occurs in the gastropod
veliger.
Which layer of the Placozoa digests food?
ventral layer
How does the nematocyst come out?
water rushes into nematocyst and the organelle everts thrusting out the filament
Spongocyte Function
Secretes spongin
Reproduction
- dioecious - sexual dimorphism
Reproduction
- dioecious, sperm packaged in a structure called a spermatophore.
Class Gastropoda
- snails and slugs - most diverse group . snails have torsion. used to expel waste. if there was no torsion they would not be able to expel waste. Down fall expelling near the head and gills.
Coiling
- spiral winding of the snail as it grows - can be right handed or left handed
A beef tapeworm has a scolex that is characterized by
0 hooks and 4 suckers.
Characteristics of Animal Bodies
1. Symmetry 2. Cephalization 3. Anatomy of Bilateral animals 4. Patterns of Development 5. Protostomes Ecdysozoan vs Lophotrochozoa 6. Body Cavity 7. Segementation 8. Digestive Tract 9. Circulatory System 10. Respiration 11. Organs for excretion 12. Support System
The class Caudofoveata contains about ________ species
120
How many layers of cells does the Phylum Placozoa have?
2 cell layers
Gastropoda is the largest class of molluscs with about ______ extant species and 15,000 extinct species described
70,000
Phylogenetic Species Concept
A basal grouping of organisms diagnosibly distinct from other such groupings with a shared pattern of ancestry. How organisms relate to each other and shared characteristics
Trematoda: Suckers or hooks?
Anterior suckers.
Members of what cnidarian class are solitary or colonial marine polyps that lack a medusa stage?
Anthozoa
The life cycle of a typical cnidarian includes both a medusa and polyp stage, However, members of class ___________________ lack a medusa stage due to likely separating from an ancestor before the medusa evolved
Anthozoans
Derived traits
Apomorphies - changed through evolution
Cnidaria: Are they normally aquatic or freshwater?
Aquatic
Who created the Typological Species Concept?
Aristotle and Linneaus
What are the three basic body plans?
Asconoid, Syconoid, Leuconoid
Where does the mouth open in trematodes and monogeneans?
At or near the anterior end.
Species
Basic unit of taxonomy
What kind of symmetry does Ctenophora have?
Biradial symmetry, paired tentacles.
Mollusks called ______ are mostly sedentary filter feeders and have two shells, no head, and no radula
Bivalves
Coelom
Body cavity (usually filled with water)
What are 3 main parts to a neuron?
Body, Dendrites, axon
Mineralization
Bones
Cestoda: Suckers or hooks?
Both
In the liver fluke Clonorchis, miracidia pass out in feces
Both ______ and _______ stages develop if ingested by water snails, and free-swimming cercariae emerge. sporocyst and redia
The asexual reproductive process involving tissue on the side of a polyp developing into another functioning polyp is known as ________________; if the new polyp stays attached to the parent polyp, a(n) _____________ is formed
Budding, colony
Budding
Buds can break off and form their own sponge
How did Aristotle classify organisms?
By splitting up physical characteristics
Who created binomial nomenclature?
Carolus Linnaeus
Who first added plants as well as animals to taxonomy?
Carolus Linnaeus
Who is the grandfather of the Typological Species Concept?
Carolus Linnaeus
The class ____________ are mostly burrowers that orient themselves vertically, with the terminal mantle cavity and gills at the entrance of the burrow, They posses an oral shield as well as a radula and gills
Caudofoveata
What are the classes
Caudofoveata, Solenogastres, Monoplacophora, Polyplacophora, Scaphopoda, Gastropoda, Bivalvia, Cephalopoda
What molluscs have a closed circulatory system?
Cephalopods
______ have the most elaborate nervous and sensory system of all of the molluscs
Cephalopods
apply to asexual reproduction in freshwater turbellarians
Chains of zooids, Regeneration, Fission
In most gastropods there is an area called the osphradium located at the base of the incurrent siphon that is _________ in some forms
Chemosensory
_________is another name for the collar cells in sponges.
Choanocyte
What are the sperm and egg produced from?
Choanocytes and archaeocytes
Asconoid description
Choanocytes line a large, central spongocoel with a single, large osculum
Syconoid
Choanocytes line radial canals that surround the spongocoel. extra surface area for more choanocytes Spongocoel is smaller, there is canals with choanocytes (filtering chambers)
Asconoid
Choanocytes line spongocoel, only food on the edge going to be filtered. Normally a small sponge. Not effective.
What is the outgroup
Choanoflagellates
What are the two types of circulatory systems?
Closed and open
type of circulatory system
Closed circulatory system - blood leaving heart goes to body tissues, then to gills, accessory hearts increase blood pressure as blood enters gill
Proximal
Closer to the medial of body
Tiny organelles contained within cnidocytes are called ___________
Cnida
Sea whips, Hydra, corals, and sea anemones members of which phylum?
Cnidaria
____________ or spiral winding of the shell occurs in the larval stage and originated in ancestral gastropods earlier than torsion
Coiling
characteristics of members of the phylum Ctenophora
Colloblasts, Biradial symmetry, Eight comblike rows of cilia
Codonsiga
Colonial flagella, trap food
When a ctenophore is swimming forward, the cilia on the ____________ plates beat in waves starting at the ____________ end of the animal and ending at the _____________ end
Comb, aboral, oral
Nemertea: Complete or incomplete digestive system:
Complete
Ctenophora: Complete or incomplete digestive system?
Complete digestive tract, but little linear specialization.
Ectoderm
Composes the outercovering of bodies, also the nervous system and skin
Class Anthazoa
Corals, Sea Anemones, Sea Whips - no medusa stage, GVC partitioned by septa, Stony corals
Operculum
Covers over the end of cnidae within cnidocytes
Choanocytes Function
Create a water current
Respiration in most gastropods is performed by a ________
Ctenidium
The majority of what group of organisms is bioluminescent?
Ctenophores
Fragmentation/Regeneration
Cut off a piece and regenerate
In terms of gastropod coiled shell formation, shells are classified as ________(right handed) or __________ (left handed)
Dextral, sinistral
Intracellular digestion
Digested in the cell
Cnidaria: What is the tissue level?
Diploblastic
In sea anemones, the mouth is in the center of a flat, oral _______, and the gastrovascular cavity is divided into radial chambers by pairs of primary _______
Disc, septa
Who created the Biological Species Concept?
Dobzhansky and Mayr
Bivalves are laterally compressed, with the two shells hinged at the _________margin
Dorsal
What are the two layers of the placozoa called?
Dorsal Epithlium (top) Ventrial Layer (bottom)
ostium
Draw water in
Heterotrophic
Eat other things to get energy
Immature life stages of the fish tapeworm develop in which of the following?
Fish, Crustaceans
What drives fluid through a flame cell?
Flagella
How does the excretory system work?
Flame cells have cilia that flicker like a flame, creates negative pressure that pushes the fluid through the tube out a pore on the side of the body. Network of tubes -freshwater have a hard time getting rid of water, but this way they can get rid of water and waste.
Phylum Platyhelminthes
Flatworms, Lophotrocozoan Protostomes, Triploblastic, Acoelomate, Most parasitic but some are free-living aquatic, Bodies dorso-ventrally flattened, incomplete digestive tract, monoecious.
Interstitial fluid
Fluid filled area between cells-the fluid is very similar to blood plasma
Hydroskeleton
Fluid filled chamber
Blood Plasma
Fluid portion of blood
Osmoregulation and excretion can be combined when these things are released together from the body,
Fluid, Waste
How is the foot modified in cephalopoda
Foot is modified for directing water as it is forced out of the mantle cavity and is fringed with tentacles (jet propulstion)
characteristics that can be found in members of the Phylum Platyhelminthes
Free-living forms, Ribbon-like body, Parasitic forms, Leaf-like body, Length varies
Lophotrocozoan Protostomes
From 1 mm to more than a meter. Blastopore in blastula forms the mouth.
Cnidaria: Complete or incomplete digestive system?
Incomplete
Platyhelminthes: Complete or incomplete digestive tract?
Incomplete
Trematoda: Complete or incomplete digestive tract?
Incomplete
What are the two types of digestive tract?
Incomplete and complete
What digestive tract does cnidaria have?
Incomplete, it is not efficient
Trace the flow of water through a syconoid sponge, starting at the top of the list with the incurrent canals
Incurrent canals, Radial canals, apopyles, spongocoel, osculum
Syconoid description
Inner choanoderm is folded into canals that lead to a spongocoel with a single osculum
Biological Species Concept
Interbreeding population of individuals that have a common descent - If they can breed together, they are the same species.
Gemmules
Internal buds, archaeocytes, aggregate and are surrounded by a spongin coat. Survive harsh conditions. Adults die in autumn, releash gemmule (little sacs) when conditions are better they can grow
Mesoderm
Is found between the ectoderm and endoderm, makes bone and muscle
Cnidaria: What layer is non cellular?
Mesoglea
What does Cindaria have instead of mesohyl?
Mesoglea
Extracellular material
Mesohyl
Which stage is missing from the life cycle of a blood fluke?
Metacercaria
What kind of excretory system
Metanephridia - excretory system - filter fluid in coelom
Choanoflagelletes and ________ are sister groups
Metazoa
What are the two parts of fossils
Mineralization and Impressions
What is the phylogeny?
Molecular evidence (rRNA - component of ribosomes - highly conservative) indicates that Porifera differentiated from flagellated protistans
Ecdysozoans
Molting, Arthropoda (shedding the exoskeleton)
_______ include all descendants and most recent common ancestor.
Monophyletic
Serial repeated organs (such as gills and metanephridia) are characteristic of the molluscan class ________________
Monoplacophora
______ are small, have a low rounded shell, and a creeping foot, and until the 1950's, they were thought to be extinct
Monoplacophora
Smart octopuses
Octopuses are very smart, can learn quickly through positive and negative reinforcement, observational learning
Prosobranchs have ____ pair(s) of tentacles, and generally separate sexes
One
how many set of gills
One set of gills - use mantle to force water flow
What kind of circulatory system do they have?
Open circulatory system (blood sometimes opens into vessels but opening into sinuses. Not efficient. does not allow a high metabolism. Good for mollusca because they do not need a closed circulatory system)
Osculum
Opening where water exits, strong enough to push far so the water doesn't get sucked back in
____________ show partial or complete detorsion resulting in the anus and gill being displaced to the right side or rear of the body
Opisthobranchs
In a polyp, which side is the oral and aboral?
Oral is on the top near the tentacles, and aboral on the bottom near the substrate.
Tissue -organ grade
Organism consists of organs - aggregates of more than one type of tissue, they perform one (i.e., a common) function.
Organ-system grade
Organisms which have organs arranged so that they can work together to perform a function. e.g. digestive system
Discharge is powered by what?
Osmotic Pressure
The ____________ is a sensory area at the base of the incurrent siphon that is chemosensory in some forms, mechanosensory in some and unknown in other gastropods
Osphradium
Sclerocyte Function
Secretes spicules
Example of Cell-tissue grade
Phylum Cnidaria: Hydra, jellyfish, sea anenome
Example of Tissue -organ grade
Phylum Platyhelminthes: flatworms
Regenerative powers:
Planarians can survive fragmentation
In terms of gastropod coiling, a __________shell lays all whorls in a single plane and a ____________ shell lays each successive whorl to the side of the preceding whorl
Planospiral, conispiral
In a typical cnidarian life cycle, a newly formed zygote develops into a motile ______________________ larva, which then settles onto a hard surface to develop into a _____________
Planula, polyp
What different varieties of respiration is there in other species?
Plasma membrane, skin, gills, tracheae, lungs
What is another name for the Phylum Placozoa?
Plate animals
Primitive (ancestral) traits
Plesimorphies - Being multicellular, mitochondria
Cnidarians are dimorphic; the larval or __________________ is sessile and attached to the substrate with tentacles extended into the water column, and the adult or _______________ form is umbrella-shaped and adapted for a floating, free-swimming lifestyle
Polyp, medusa
Molluscs called chitons belong to the class
Polyplacophora.
Characteristics of the Phylum Porifera
Pore bearing, siphon water, sessile
_____ are tubular cells that form pores, while ______ are ameboid cells in the mesohyl with various functions
Porocytes; archaeocytes
Outgroup
Possess all of the ancestrial traits that the other species have. Does not have derived traits
The ______ contain most of the marine snails and some freshwater and terrestrial gastropods
Prosobranchs
Phylum Nemertea
Ribbon worms, About 1000 marine species, most small < 20 cm longSimilar to Planaria, but, dioecious, proboscis, complete digestive system, Simple circulatory system
Tusk shells and tooth shells are burrowing marine molluscs in the class _______
Scaphopoda
What can archaeocytes turn into
Scleroctyes
Members of what cnidarian class have the following characteristics: a medusa stage ranging from 2 cm to 2 m in diameter, a bell that lacks a velum and can vary from a shallow saucer shape to a deep helmet or goblet shape, and sense organs called rhopalia?
Scyphozoa
What cnidarian often enters into mutualistic relationships with other organisms including dinoflagellates, hermit crabs, and damselfishes?
Sea anemones
Pedal Laceration
Sea anemones crawl across the ocean floor leaving pieces of cells that will grow into new cnidaria.
Lophocyte Function
Secretes large quantities of collagen
species found in Class Calcarea
Sycon, Leucosolenia, Clathrina
Columnar
Taller than cuboidal
Law of Priority
The person that discovered it first should be able to keep their name there
How is the person who discovered the species listed?
The person who gave that name is listed after the scientific name. If the name is in brackets it means the name has changed due to evidence of changing taxonomy, if there is not brackets it means it is in the right genus and species.
dimorphic nature of cnidarians
The polyp stage is sessile, while the medusa stage is free-swimming/floating
Radiate animals have which of the following characteristics?
The process of gastrulation during development, Two embryonic cell layers (endoderm and ectoderm), Presence of a gut cavity
In hydroid colonies, polyps may be _________, indicating that the perisarc creates a protective cup around the polyp and functions in protection, or ___________ when there is no such protective cup
Thecate, athecate
describe feeding in hydras
Their diet often consists of small crustaceans, insect larvae, and annelid worms. The mouth opens into the gastrovascular cavity.Nematocysts found in the tentacles are used to subdue prey.
characteristics of the turbellarians?
Their gut can be simple, branched, or absent. They can be up to 50 cm long. Most are free-living.
Cnida
Tiny capsule containing a coiled thread or filament
Budding:
Tissue on the side of a polyp develops into another polyp that stays attached to the parent polyp
Pedal laceration:
Tissue torn from the basal disc develops into tiny new polyps
Interstitial cells:
Transforming into other cell types, such as cnidoblasts, sex cells, buds, nerve cells, etc.
platyhelminths that do not have a ciliated tegument
Trematodes, Cestodes, Monogeneans
In many molluscs, a free-swimming ______ larva emerges from the egg stage
Trochophore
In general, embryos of marine bivalves go through three larval stages: , __________, ___________, and young spat
Trochophore, veliger
True or false: Sponges have a blastula stage during development, similar to that seen in other animals.:
True
Opisthobranchs usually have _______ pair(s) of tentacles with the one pair often further modified for chemoreception
Two
Cestode
Two canals join to form excretory bladder that opens by a terminal pore.
Monogenean
Two lateral excretory pores open laterally
What are the two concepts of Typological Species Concept?
Type Locality and Type Specimen
In bivalves the shell grows in concentric circles around the _________
Umbo
What is the assumption of the biological species concept?
Under the assumption of only reproducing sexually and not asexually
Examples of Protoplasmic grade
Unicellular : Kingdom Protista paramecium
Where does a cestode latch on to the host?
Upper intestine.
Autotrophic
Uses energy from sunlight to make food. Fixation carbonation
Scallops swim with a jerky motion that creates jet propulsion by clapping their ______ together
Valves
After a cnidarian nematocyst receives a stimulus to discharge, ____ rushes into the capsule, causing the ____________ open and the filament to be turned inside out, This exposes the barbs, which can then be used to inject toxin
Water, operculum
What kind of digestive system
Well developed complete digestive system - radula (rasping tongue away from hard surface, scrap up food)
Bone
cells (Osteocytes) embedded in a hard calcified matrix
Cartilage
cells (chondrocytes) and fibers embedded in a spongy matrix
Blood
cells (erythrocytes{RBC/oxygen}, leukocytes{WBC/Infection}) and particles (platelets{clotting}) dispersed in a fluid matrix (plasma)
Loose connective tissue
cells and fibers are interspersed in matrix
Nervous Tissue
cells are specialized for communication.
Neurons
cells of nervous tissue, communicate impulses
Sclerocytes
cells that form mineral spicules
Porocytes
cells that form tubes through which water flows to enter the sponge
Archaeocytes
cells that travel through the body and are thought to distribute nutrients from chaonocytes to the rest of the cells.
The class Polyplacophora contains molluscs called
chitons.
Sperm are released through the osculum and are phagocytiozed by a ______________ of other sponge
choanocyte
In terms of gastropod shell coiling, ______ shells are more compact
conispiral
Body of a neuron
contains the nucleus and other various organelles
The host in which a trematode undergoes sexual reproduction is called the final or _____________________ host
definitive
In sponges, the openings of the invaginations of the body wall are called incurrent canals or
dermal pores
Incoming water enters a sponge through
dermal pores
Nemertea: Monoecious or dioecious?
dioecious
Most molluscs are
dioecious.
specific epithet
does not indicate relatedness
The mantle fold edges in bivalves are modified to form ______ excurrent and ______ incurrent openings
dorsal; ventral
Simple cubodial epithelial
ducts of body, kidney ducts
Polymorphism
during life-cycle, individuals may have different body shapes.
Trematodes, monogeneans, cestodes, and some turbellarians exhibit a derived condition called ______ development, in which female gametes contain little or no yolk, and yolk is contributed by cells that surround the zygote
ectolecithal
The epidermal layer of Hydra contains numerous different cell types with different functions, For example, most of the epidermis is comprised of __________ cells, which function to cover the body and for muscular contraction
epitheliomuscular
Respiration
exchange of gases, intake of O2 and release of CO2
How do Porifera feed?
filter feeders, intracellular digestion. Bring in large amounts of water to get food and oxygen and get rid of waste products. Singular flagellum that will beat and when it beats back and forth it will bring the water in from an area made of microvilli (act as a net)
Sessile
fixed in one place; immobile, on corals or ocean floor
Choanocytes (collar cells)
flagellated cells with a netlike structure for filtering food from water.
The protonephridia of most platyhelminthes end in specialized cells called
flame cells.
Squamous
flattened, form thin lining
Body cavity
fluid filled cavity in body that gives support and flexibility to the body -classification based on position in primary germ layers
Trematodes are known as ______, and almost all are ______ of vertebrates
flukes; endoparasites
Bivalves initiate movement by extending their muscular ___________ between the valves, pumping blood into it, and causing it to swell and act as an anchor in mud or sand
foot
Impressions
footprints
Pinacocytes
form the outer layer of cells of a sponge can phagocytize food trapped on the surface of the sponge are similar to epithelial tissue but lack a basal membrane.
An asexual form of reproduction where a sponge breaks into parts that go on to form new individuals is called
fragmentation
Distal
further from medial of body
Sponges are monoecious
hermaphrodite
Fasciola hepatica adults live
in the bile duct of the host.
Nervous system
is very well developed- largest brain of any invertebrate
The Phylum Placozoa
lacks symmetry and organs has only one species represented.
Spongocoel
large chamber in the middle
Monoecious:
large gonads, in proglottids, both eggs and sperm
Glochidium larva
larva of mussels unique disperion either released, or use fish to disperse. using the fish they have a modified mantle that will look like a fish species that other predatory species might want to eat. And when the fish goes to take a bite, the larva will get stuck in the gills of the predatory fish and feed off the blood supply of the gills of the fish until they get big and fall off.
Basement membrane
layer of extracellular material that separates epithelium from the tissue it is covering. transitional epithelium ex. bladder
Dense (fibrous) connective tissue
ligaments, tendons, fascia
specific epithet/ Species
most exclusive taxon
Are Porifera larvae sessile or motile?
motile, they swim around until they find a good place to grow
In bivalves, respiratory currents bring in both oxygen and organic particles to the gills, where ciliary action and mucous eventually take food to the
mouth.
Metazoans
multicellular organisms and after animals and kingdom animalia
Cellular grade
multicellular, specialized cells, no tissues. More than one cell working together.
Transitional Stratified
multiple layers that allow stretching
Muscle
muscle cells are called fibers. They are elongated cells specialized to contract. actin and myosin
The diffuse nervous system of cnidarians can best be described as a:
nerve net