Bio 102

Millipedes and Centipedes Millipede and centipede translate to

"thousand feet" and "hundred feet" and refer to the enormous numbers of legs on these long, skinny animals.

Division based upon gut development tells us if the animal is

- Protostomes: "mouth first" -Deuterostomes: "mouth second"

what are the cnidarian members

- jelly fishes -sea anemones -corals

Sponges

- no tissues or organs -body consists of hollow tube or network of canals with pores in their walls -feed by pumping in water along with bacteria, algae and small particles of organic materials of organic through their pores -free swimming larvae -sessile as adults

common characteristics of cnidarians

- radialy symmetrical -Tentacles armed with rows of singing cells, used to paralyze prey -

The flatworms common characteristic is

- well defined head and tail regions -Grow by adding mass -Hermaphroditic and can engage in both sexual and asexual reproduction -some have a single opening for their digestive tract which serves as a mouth and anus

what is the anatomy of a sponge

-Body is filled with passageways for water -Epidermal cells -collar cells -flagellum -amoboyte -pore -gel layer

Nautiluses

-Chambered shell used for protection -Free swimming - 6 species

worms have

-Defined tissues -Protostome development -Bilateral symmetry

millipedes and centipedes

-Many pairs of legs (two pairs per segment in millipedes; one pair per segment in centipedes) -Long, segmented body

Radial symmetry animals have

-No front or back end -"pie-like" body plan -Corals, sea anemones, and jellyfishes

Bilateral symmetry

-Right and left sides that are mirror images -Adept movement possible -At any life stage

what are some members of mollusks

-gastropods about 35000 -bivalve about 8000 -cephalopods about 700

what are the common characteristics of roundworms

-long narrow unsegmented body -surrounded by a strong flexible cuticle -must molt in order to grow larger

Crustaceans

-many pairs of legs -usually five pairs of appendages that extend from the head -mostly aquatic

what are some members of annelid

-marine polychaetes (9,000 species) -earthworms ( more than 4,000 species) -leeches (500 species)

what are the members of roundworms

-more than 90,000 species (scientist estimate there may be five times as many species not yet identified

what are some common characteristics of mollusks

-most have a shell that protects the soft body -mantle tissue that forms the shell --radula sandpaper like tongue structure used during feeding found in all mollusks except bivalves

what are the common characterisitics of annelid

-segmented body -grow by adding body mass

what are the flatworms members

-tapeworm -flukes

Arachnids

-usually live on land, -usually have four pairs of walking legs and a specialized pair of feeding appendages, and -include spiders, scorpions, ticks, and mites

Four key distinctions divide the extant animals into monophyletic groups

1) Tissues or not 2) Radial or bilateral symmetry 3) Protostome or deuterostome development 4) Growth through molting or through continuous addition to the body

Four key distinctions divide the animals

1. Does the animal have specialized cells that form defined tissues? 2. Does the animal develop with radial symmetry or bilateral symmetry? 3. During development, does the animal's gut develop from front to back or back to front? 4. Does growth occur by molting or by adding continuously to the skeletal elements?

Generally, the appropriate placement of species in a phylogenetic tree is based on answers to the following questions?

1. Does the animal have specialized cells that form defined tissues? 2. Does the animal develop with radial symmetry or bilateral symmetry? 3. During gut development, does the mouth or anus form first? 4. Does growth occur by molting or by continuous addition to the animal's body?

what are the steps of the attack by cnidocyte in cnidarians

1. prey comes in to contact with the trigger 2. the coiled thread is ejected, penetrating the prey 3. A toxin is injected to paralyze the prey

Terrestrial vertebrates are descendants of lobe-finned fishes that lived during the Devonian period, approximately: 300 million years ago. 200 million years ago. 500 million years ago. 100 million years ago. 400 million years ago

400 million

Animals without backbones represent more than ______ of the total species in the animal kingdom.

95%

Invertebrates comprise more than _______ of all living animal species

95%

coral bleaching

A phenomenon in which algae inside corals die, causing the corals to turn white.

Which of the following about insects is false, All insects are arthropods. Insects have a tough exoskeleton that acts like body armor. All insects have three life stages: larva, pupa, and adult. Wings and the ability to fly first appeared in insects. The primary role of an adult insect is to reproduce.?

All insects have three life stages: larva, pupa, and adult. Not all insects go through three distinct life stages; about 83% of insect species do. Some insects, like grasshoppers, only have two stages, nymph and adult, which is known as incomplete metamorphosis.

Which of the following species living today is the most evolutionarily successful? the house mouse (Mus domesticus) the housefly (Musca domestica) the Western gorilla (Gorilla gorilla) the irukandji, the most toxic box jellyfish (Carukia barnesi) All of the above

All of the above

Which of the following species living today is the most evolutionarily successful?

All of the above species are equally successful because they are not extinct.

Ectotherm

An animal whose body does not produce much internal heat

What is a vertebrate?

An animal with a backbone

What is a invertebrate?

An animal without a backbone

What is an invertebrate?

An animal without a backbone

What are cephalopods?

An ocean dwelling mollusk whose foot is adapted to form tentecles

You find a protostome that has a closed circulatory system and a segmented body. In which of the following phylum does it most likely belong?

Annelida Annelids, or segmented worms, have segmented bodies. Also, unlike flatworms, which have no specialized circulatory organs, annelids have a closed circulatory system.

bilateral symmetry.

Body plan in which only a single, imaginary line can divide the body into two equal halves. These organisms (such as humans, cows, and scorpions) have left and right sides that are mirror images.

squids

Cephalopoda -8 short tentacles and 2 long sucker bearing tentacles -free swimming -300 species

what are some examples of bivalve mollusks

Clams, scallops, oysters, and mussels are examples of bivalves. There are about 8,000 bivalve species and most of them live in the ocean, although there are some freshwater species

examples of bivalve mollusks are

Clams, scallops, oysters, mussels

What is phylogeny?

Evolutionary history of a species

True or false: Animals with backbones are more evolutionarily successful than organisms without backbones. False. The fact that there is more diversity among invertebrates indicates they are more successful than vertebrates. False. This adaptation reduces flexibility and hinders a vertebrate's success in their environment. False. The energy required to produce this structure takes away from vertebrate's ability to reproduce. False. Each species exhibits adaptations that best suit their environment. True. This adaptation enables vertebrates to be more successful in their environment.

False. Each species exhibits adaptations that best suit their environment. The study of evolution does not rank species as more or less successful. Each species possesses a combination of various adaptations that enable them to be successful (e.g., find food, escape predators, and reproduce) in their environment.

Annelids develop from

Front to back

What is a cnidocyte thats found in cnidarains?

Injects venom into prey and paralyzes it

What is a polyp?

Is a form of a cnidarians that is immovable. They have upright tentacles located near the mouth.

What is a deuterostome?

It is an animal whose anus is formed from the blastopore.

What is the relationship between coral and zooxanthellae?

Mutually symbiotic; zooxanthellae provide the coral with nutrition, while the coral provide zooxanthellae with carbon dioxide. Both of these organisms depend on each other for survival.

What is the relationship between coral and zooxanthellae? -Parasitic; zooxanthellae are a type of algae that grows inside coral, --feeding off of the coral's nutrients and causing coral bleaching over time. -Competitive; zooxanthellae are a type of algae that compete with coral for space and nutrients. -Mutually symbiotic; zooxanthellae provide the coral with nutrition, while the coral provide zooxanthellae with carbon dioxide. -There is no relationship between the two. Zooxanthellae are terrestrial animals, and coral is aquatic. -Commensal; zooxanthellae are a type of algae that resides among the coral, but the coral is unaffected by its presence.

Mutually symbiotic; zooxanthellae provide the coral with nutrition, while the coral provide zooxanthellae with carbon dioxide. Both of these organisms depend on each other for survival.

Corals are of what group

Phylum Cnidaria

Which of the following is an animal with rigid bones, jaws, and a swim bladder?

Salmon have a rigid skeleton of bone, jaws, and an air bladder.

Bivalve Mollusks are

Soft-bodied animals with a pair of hinged shells

what are some examples of invertebrates?

Some would include sea stars, worms, and jellyfish.

What is a gastropod?

Stomach-footed mollusks with single shells like snails

Sea stars, a type of echinoderm, are seemingly harmless organisms. Which of the following, if any, is a defense/predation mechanism of the sea star? -The tube feet create a combined force to pull apart shells of a clam or mussel. -The stomach can be pushed out through the mouth into a slightly opened clam shell, secreting digestive enzymes. -Sharp, tooth-like surfaces can scrape algae loose from rocks. Streams of mucus can be used to capture food. -The first two choices are correct

The first two choices are correct

What is the key difference between protostomes and deuterostomes? -Protostomes represent animals that are prokaryotes, and deuterostomes represent all over animals. -Protostomes represent a lineage of bilaterally symmetrical animals, whereas deuterostomes represent a lineage of radially symmetrical animals. -The protostome gut develops from back to front and the second opening becomes the mouth. The deuterostome gut develops from front to back, so the first opening is the mouth. -The protostome gut develops from front to back, so the first opening is the mouth. The deuterostome gut develops back to front, and the second opening becomes the mouth. -Protostomes are animals with soft exteriors and deuterostomes are animals with hard exteriors (i.e., shells).

The protostome gut develops from front to back, so the first opening is the mouth. The deuterostome gut develops back to front, and the second opening becomes the mouth. The way in which their gut develops is the difference between the two.

What is the key difference between protostomes and deuterostomes?

The protostome gut develops from front to back, so the first opening is the mouth. The deuterostome gut develops back to front, and the second opening becomes the mouth. The way in which their gut develops is the difference between the two.

Zooxanthellae symbionts is needed to

The zooxanthellae can provide all the nutrients necessary, in most cases all the carbon needed for the coral to build the calcium carbonate skeleton.

Which of the following is true of all animals?

They are capable of movement at some stage of their life cycle.

What is a monophyletic group?

a common ancestor and all of its descendants

•About 630 million years ago,

a major evolutionary split occurred in animals.

Some cnidarian species spend part of their life cycle as ________ or _________

a polyp and part as a medusa.

There are two types of cnidarian bodies

a sessile polyp and a free-floating medusa.

Most mollusks have a shell for protection, a mantle of tissue that wraps around their body, and

a specialized tongue called a radula.

Mammals are classified as amniotes

amniotes

Terrestrial vertebrates are classified either as amniotes or non-amniotes. Which of the following animals is a non-amniote?

amphibians

What is a protostome?

an animal whose mouth is formed from the blastopore

"Belly foot" means the species has

an expanded foot on the bottom of the body that allows for mobility

snails and slugs live in

aquatic and terrestrial environments

how does chordates (such as monkeys, humans and dogs etc) develop

back to front

how does echinoderms ( such as start fish etc) develop

back to front

Birds are grouped with turtles, lizards, snakes, alligators, and crocodiles. Birds, however, have feathers and can generate their own body heat, which other reptiles cannot do. Which of the following likely explains the original evolutionary function of feathers in early reptiles? behavioral displays flight insulation structural support locom

behavioral displays The original function of feathers in early reptiles most likely was courtship behavior.

Which of the following characteristics could not be used to differentiate the three worm phyla, Annelida, Platyhelminthes, and Nematoda? -segmentation -the presence of eyespots -bilateral symmetry -presence of a complete gut, with two openings -growth by molting

bilateral symmetry All three of these worm phyla have bilateral symmetry.

Which of the following characteristics defines a chordate?

bilateral symmetry, defined tissues, and gut develops from back to front All chordates exhibit bilateral symmetry, have defined tissues, and have a gut that develops from back to front.

All worms are _________ symmetrica ________ with defined tissues

bilaterally , protostomes

The notochord that characterizes all chordates at some stage in their life cycle provides all of the following functions except: -a base for trunk muscles. -makes locomotion possible by stiffening when muscles contract. -bony protection for the nerve cord. -a longitudinal stiffening of the main body axis. -an axis around which the vertebral column develops.

bony protection for the nerve cord. In complex chordates the notochord is only present in the early embryo. It is then replaced by the backbone. Challenge this Questio

All animals share a common ancestor

both trees indicate that animals are monophyletic, forming a clade called Metazoa

Sponges reproduce asexually by

budding

how does growth occur for annelids

by adding

how does growth occur for flat worms

by adding

how does growth occur for mollusks

by adding

The development of jaws allowed fishes to: withstand the pull of gravity. capture and kill prey. acquire dissolved oxygen from water. float in water. control their movement in water.

capture and kill prey. Jaws lined with sharp teeth allowed fishes to seize and chew prey. Before the development of jaws, aquatic vertebrates were either gained nutrients by filter feeding or attaching an oral disk to prey. Challenge this Qu

All cnidarians are

carnivores and use specialized stinging cells located in their tentacles to capture prey.

The third major group of mollusks is the

cephalopods, It includes 6 nautilus species and more than 600 species of squids and octopuses.

Cephalopods include all of the following kinds of animals except: squid. octopuses. clams. nautiluses. All of these organisms are cephalopods.

clams. Clams are bivalve mollusks with a soft body, protected by a pair of hard shells that are hinged together by a ligament.

cnidarains capture there prey using

cnidocytes

All cnidarians have tentacles that are armed with rows of stinging :cilia. flagella. cnidocytes. polyps. collar cells.

cnidocytes. Cnidocytes are stinging cells that cnidarians use to capture prey.

Each Cnidocyte in cnidarian contains a

coiled thread with barbs inside and a trigger on the outside

Nearly one-third of amphibian populations are facing extinction. Which of the following does not attribute to the universal decline in amphibian populations? competition from mammals fungal disease climate change habitat destruction polluti

competition from mammals

Which of the following types of arthropods are not primarily land-dwelling? centipedes crustaceans arachnids millipedes insects

crustaceans Crustaceans are primarily aquatic organisms. They include lobsters, crayfish, crabs, and shrimp. Challenge thi

In the United States, the top three fishery crops, by annual market value, are

crustaceans: shrimp, crabs, and lobsters.

radial symmetry

describes animals with bodies structured like pies, such as jellyfishes, corals, and sea anemones

Certain adaptations have led to the rapid and extensive

diversification of particular groups of species.

All animals acquire energy by

eating other animals

All invertebrates, however, are protostomes—except for one large group, whose members are all deuterostomes. Called the

echinoderms, and including sea stars, sea urchins, and sand dollars, this animal phylum shows the same from-back-to-front gut development as the vertebrates, and these animals are the vertebrates' closest relatives.

Sponges reproduce sexually by eggs and sperm

eggs and sperm

long, skinny, slimy animals without backbones, Animals fitting this description occur in

eight different phyla.

Some cnidarian species exist only in one form or the other which

either only as polyp or only as medusa

All bivalves are

filter feeders

Which of the following anatomical characteristics of humans can be traced back to our arboreal origins, forward-directed eyes mammary glands increased caloric intake large brain size exothermic temperature regulation?

forward-directed eyes Forward-directed eyes as well as binocular vision allow for distances to be judged accurately. It is one of the adaptations traced back to life in the trees.

Which of the following anatomical characteristics of humans can be traced back to our arboreal origins? mammary glands large brain size exothermic temperature regulation increased caloric intake forward-directed eyes

forward-directed eyes Forward-directed eyes as well as binocular vision allow for distances to be judged accurately. It is one of the adaptations traced back to life in the trees.

There are about 60,000 species of chelicerates, a group that includes

four horseshoe crab species and the arachnids, land-dwelling arthropods that include spiders, scorpions, mites, and ticks. Most have four pairs of walking legs and a specialized feeding apparatus.

cnidarian Medusas are

free-floating

Slow-moving or free-floating, radially symmetrical animals have no

front or back ends. It is possible to make multiple slices through the center that divide the organism into identical pieces.

Arthropods develop from

front to back

Flat worms develop from front to back or back to front

front to back

Mollusks develop from

front to back

Roundworms develop from

front to back

In which of the following animals does the mouth develop before the anus during gut development, humans monkeys sponges starfishes fruit flies ?

fruit flies

In which of the following animals does the mouth develop before the anus during gut development? sponges monkeys starfishes humans fruit flies

fruit flies All arthropods, including insects such as fruit flies, are protostomes, meaning their gut develops from front to back.

Snails and slugs are __________ mollusks

gastropod

A new animal is discovered with a prominent muscular foot that attaches to underwater rocks. The animal also has a one-piece shell. To which of the following animal groups does this new animal belong? gastropods crustaceans bivalves echinoderms cephalopods

gastropods This is the largest group of mollusks and includes both terrestrial and aquatic organisms.

three of the major groups of mollusks

gastropods, bivalve mollusks, and cephalopods

Coral reefs are

hard external skeletons secreted by coral animals (Cnidaria).

what is bivalve mollusks

he bivalve mollusks are soft-bodied animals protected by a pair of shells hinged together by a ligament.

millipedes are

herbivores that feed on dead plant material.

Flatworms, roundworms, and segmented worms come

in all shapes and sizes

This general body plan has,

independently, evolved several times.

Fertilized eggs grow into free-swimming

larvae that settle and develop into sessile, filter-feeding adult sponges

sponges are amongst the simplest of

lineages

"Worm" is a term usually applied to

long, skinny, slimy animals without backbones

An air environment, gravity, and desiccation are three challenges that were addressed in the evolution of reptiles. What three evolutionary innovations addressed these challenges? -gills, bony skeleton, and lungs -dorsal nerve cord, notochord, and a post-anal tail -lungs, better limb support, and the amniotic egg -better limb support, gills, and pharyngeal slits -the amniotic egg, sturdy fins, and a cartilaginous skeleton

lungs, better limb support, and the amniotic egg Fins were modified into limbs. Vertebrae were modified to transmit body weight through the limbs to the ground. The site of gas exchange was transferred from gills and swim bladders to lungs. Finally, terrestrial vertebrate eggs with membranes and a shell resisted drying out.

Some insects have a life history that is divided into two or three unique stages known as ____________, during which their bodies undergo distinct changes.

metamorphosis The process of metamorphosis allows insects to overcome the constraints of having a rigid exoskeleton, which prohibits growth.

Flatworms and segmented worms (annelids) do not _______; the roundworms do.

molt

Mollusks are protostome invertebrates that do not

molt.

how does growth occur for arthropods

molting

how does growth occur for roundworms

molting

"Worms" are not a _______ group

monophyletic

Worms are found in several different phyla and are not a _____ group

monophyletic

all animals have the ability to

move

Trichinella worms sometimes cause the disease known as trichinosis in humans when undercooked pork is eaten. These organisms have long cylindrical bodies but no segmentation. This species is most similar to which of the following animals? Portuguese man-o'-war nematodes earthworms jellyfish flatworm

nematodes These worms are not segmented and have a cylindrical shaped body.

Of the approximately three dozen animal phyla,

nine phyla account for more than 99% of described animal species.

Do sponges have difined tissues

no

In complex chordates, such as vertebrates, the ____________ is eventually replaced by a vertebral column. notochord rigid exoskeleton hollow dorsal nerve cord post-anal tail ventral solid nerv

notochord

In complex chordates, such as vertebrates, the ____________ is eventually replaced by a vertebral column

notochord In more complex chordates, the notochord in early embryos is replaced by a vertebral column, or backbone, as the embryo develops.

There are about 52,000 species of crustaceans, and although crustacean species can look very different—from sessile barnacles to mobile, tiny krill—they have

one feature in common: five pairs of appendages extending from the head. Three of these appendages are used for feeding, and two are antennae that sense the environment.

The arthropods are protostome invertebrates; with nearly

one million species (and at least as many more yet to be identified), they outnumber all other forms of life in species diversity.

The pattern of embryonic gut development is

one of the most basic divisions of animals

DNA and RNA analyses are used to

organize animal species into monophyletic groups.

All animals eat

other organisms

Are invertebrates monophyletic or paraphyletic?

paraphyletic

Many roundworms are ___________ of plants or animal and are responsible for several widespread human diseases

parasites , animals

Flatworms include __________ and __________, many of which infect humans.

parasitic flukes, tapeworms

Bivalves form a __________ when a grain of sand is trapped in the mantle tissue

pearl

Animals having no tissues—groups of cells with a common structure and function—belong to the

phylum Porifera

Two types of body plan in cnidarians

polyp and medusa

Sea anemones are

polyp forms of cnidarians

Centipedes are

predators with fangs that inject venom,

Spiders and scorpions are

predatory arthropods that eat insects and, occasionally, small vertebrates

Lobsters, crabs, shrimp, and barnacles are

predatory marine crustaceans

The worms have defined tissues and are

protostomes—the gut develops from front to back.

Which of the following correctly pairs a stage of arthropod metamorphosis with its most significant change at that stage? -larva: embryological growth and change occurs at this stage -pupa: body structures of the larva are broken down and reassembled -pupa: the pupa eats and grows large enough to become an adult -zygota: the sperm and the egg unite -adult: changes occur throughout the entire adult life until reproduction

pupa: body structures of the larva are broken down and reassembled This is the actual defining stage of metamorphosis, when the larva encloses itself in a case, body structures are broken down, and new structures are assembled into adult form.

All animals with defined tissues develop

radial or bilateral symmetry

do Cnidarians have bilateral or Radial symmetry

radial symmetry

Corals, sea anemones, and jellyfishes are

radially symmetrical animals with defined tissues, in the phylum Cnidaria.

Earthworms are annelids that play an important role in

recycling dead plant material.

Slugs have a

reduced shell

Octopuses

sea creatures with eight long tentacles -bottom dwellers living in coral reefs and on rocky coasts -300 species

Polyps cnidarians are

sessile meaning they dont move

Most mollusks live in

shell

•Snails have a _________ for protection.

shell

Slugs use __________ for protection

slime

Corals live as

small polyps in large colonial groups.

Which of the following organisms does not contain chitin? scorpions snails grasshoppers lobsters crabs

snails Snails' shells are composed of calcium.

examples of gastropods

snails and slugs

They are the second most diverse phylum of animals and include

snails and slugs, clams and oysters, and squids and octopuses

They are the second most diverse phylum of animals and include

snails and slugs, clams and oysters, and squids and octopuses.

Which animal is an ectotherm, human hawk snake sea lion dolphin?

snake

Which animal is an ectotherm?

snake

Which is the only animal phylum to not possess true tissues? Please choose the correct answer from the following choices, and then select the submit answer button. sponges

sponges

Which of the following is not an arthropod?

squid

what are members of cephalopods

squids octopuses nautiluses

Which of the following organisms is not a chordate? -lancelet -tunicate -reptile -stingray -starfish

starfish A starfish is not a chordate; it is found in the echinoderm phylum.

Which of the following is not one of the major evolutionary adaptations that occurred as animals moved from water to land? -four legs -lungs -eggs that resist drying out -swim bladder -a rigid backbone

swim bladder A swim bladder is homologous to the lungs of land-dwelling vertebrates and is not one of the major evolutionary adaptations that occurred as animals moved from water to land.

Which of the following types of worms include species that are internal parasites? polychaetes tapeworms slugs leeches earthworms

tapeworms All 5,000 species of tapeworms are parasitic, living in a host's gut and absorbing nutrients directly through their body wall.

Although most crustaceans are aquatic, the inconspicuous wood lice (also known as pill bugs, sow bugs, or roly-polies) are

terrestrial forms that you can find when you turn over a rock in your garden. Wood lice are herbivores and play an important role in recycling dead plant material.

Great Barrier Reef

the largest coral reef in the world

With adaptations that include the ability to fly and metamorphosis, insects are

the most diverse group of arthropods.

Jellyfishes and other cnidarians are among

the most poisonous animals in the world.

Roughly 8,000 species of bivalve—most of them live in

the ocean

The lineage that first separated from the common ancestor of all animals, and retains many of the same primitive features to this day, includes which of the following modern organisms?

the sponge

Animals are multicellular

their bodies contain distinct types of cells that are specialized for different functions

insects have

three pairs of walking legs legs located on the thorax life cycle with seperate life stages

snails and slugs account for

three-quarters of all mollusks.

sponges are animals that lack

tissues and organs

a sponge has no

tissues or organs

there are no lower or higher species?

true

The most ancient branching point in the phylogeny of animals is the one that distinguishes between having

true tissues or no tissues. Sponges in the phylum Porifera do not have true tissues; all other animals have clearly defined tissues.

What is an arthropod?

type of invertebrate covered by a hard lightweight outer skin or exoskeleton

Most mollusks have a shell for protection, a mantle of tissue that

wraps around their body, and a specialized tongue called a radula.

Do Cnidarians have true tissues?

yes

The arthropod phylum is so large that, even if we excluded all the insects

—the most diverse arthropod group—it would still contain more species than any other phylum.

A phylogeny is a hypothesis

•Hypotheses are subject to revision. -Are sponges really the first evolutionary lineage to split from the rest of the animals? -Or were ctenophores the first animal group to diverge? •New phylogenies change our understanding of events in evolutionary history.

Describe sea anemones

•Resemble flowers • •Tentacles with cnidocytes surround the mouth • •Free-swimming larval stage • •Sessile adult stage (mostly) - Many sea anemones can slowly crawl.

Does growth occur by molting or continuous addition to the animal body?

•Some animals shed an exoskeleton during development. -Lobsters, insects •Some animals add to their body plan in continuous increments. -Clams, octopuses

describe Jellyfishes

•They are not fishes at all! • •Range tremendously in size - Asian giant jellyfish - •Some species are deadly - Irukandji jellyfish