Invertebrate Zoology by

Invertebrate Zoology by https://padlet.com/mikelgarcia6/mjhv9f8i0ef7 Overview of Nine Phylum en-us 2017-10-24 15:25:01 UTC 2025-12-25 22:09:11 UTC hello@padlet.com Porifera mikelgarcia6 https://padlet.com/mikelgarcia6/mjhv9f8i0ef7/wish/200045893 Embryological Developmental Characteristics
- Asymmetric, doesn't have a mouth, acoelomate, no embryonic germ layers, immobile, feeds on material suspended in water, basal, Has a distinct larval stage which is planktonic, Lives in aquatic environments, mostly marine., All are filter feeders

Major Groups within phyla
- the Hexactinellida (glass sponges)
- the Demospongia
- the Calcarea (calcareous sponges)
Distinction of how groups are different
- Sponges are characterized by the possession of a feeding system unique among animals.

Important Anatomical characteristics
-tiny pores in their outer walls through which water is drawn. Has no nervous system, Often have a skeleton of spicules.

Important life cycles within groups

- hermaphroditic, they function as either male or female for reproduction
- can produce eggs and sperm at different points in time
- Reproduce sexually or asexually,

]]> 2017-10-24 15:29:32 UTC https://padlet.com/mikelgarcia6/mjhv9f8i0ef7/wish/200045893 Cnideria mikelgarcia6 https://padlet.com/mikelgarcia6/mjhv9f8i0ef7/wish/200046047 Embryological Developmental Characteristics
- armed with stinging cells called nematocysts, live from the tropics to the poles, from the surface to the bottom, sometimes known as coelenterates,

Major Groups within phyla and Distinction of how groups are different
Anthozoa, which includes true corals, anemones, and sea pens;
Cubozoa, the amazing box jellies with complex eyes and potent toxins;
Hydrozoa, the most diverse group with siphonophores, hydroids, fire corals, and many medusae; and
Scyphozoa, the true jellyfish.

Important Anatomical Characteristics
radially symmetrical body shape with a mouth surrounded by rings of tentacles. body is diploblastic, with two cell layers of the body wall separated by mesoglea,

Important life cycles within groups
- all have a life cycle of two forms.
- free-swimming jellyfish medusa stage
- an attached polyp stage

Polyps: wait for prey to come by
Medusas: flattened mouth, drift with ocean currents ]]> 2017-10-24 15:29:44 UTC https://padlet.com/mikelgarcia6/mjhv9f8i0ef7/wish/200046047 Rotifera- the "wheel animalcules" mikelgarcia6 https://padlet.com/mikelgarcia6/mjhv9f8i0ef7/wish/200046212 Embryological Developmental Characteristics
-they're considered animals rather than bacteria or protozoa.
very small size and mostly soft bodies, but only hard part is their jaw

Major Groups within phyla and Distinction of how groups are different
- Monogononta- with about 1500 species
- Bdelloidea- with about 350 species
- Seisonidea (most primitive)- only two known species

Important Anatomical Characteristics
- Four parts
-head -supports a series of mobile tentacles called cilia, which propel water into the organism's mouth
-neck - contains a throat-like tube that funnels water into the rotifer's stomach and other organs
-body - stomach and other organs are located in the body section
-foot - protrudes from the organism's rear as an oar or spine to give the rotifer some control over its movement in liquid environments.

Important life cycles within groups
- Reproduction is by parthenogenesis in most species, while sexual reproduction with separate sexes also occurs in some groups. In parthenogenetic species, eggs are produced by mitosis and always hatch into females.
- grow larger as the organism ages, but they don't increase in number. Female rotifers are larger than males and are able to reproduce asexually without the help of a mate. A male and female can produce offspring through sexual reproduction during direct physical contact.]]> 2017-10-24 15:30:02 UTC https://padlet.com/mikelgarcia6/mjhv9f8i0ef7/wish/200046212 Platyhelminthes mikelgarcia6 https://padlet.com/mikelgarcia6/mjhv9f8i0ef7/wish/200046563 Embryological Developmental Characteristics
- bilaterally symmetrical and triploblastic, acoelomates, they have organ systems, Generally dorsoventrally flattened, Mostly they feed on animals and other smaller life forms, Some species occur in all major habitats, including many as parasites of other animals.

Major Groups within phyla and Distinction of how groups are different
- Turbellaria- a soft epidermis that is ciliated, at least on the ventral surface
- Trematoda- have oral suckers, sometimes supplemented by hooks, with which they attach to their vertebrate hosts
- Monogenea- parasites on a single host, often on the gills and skin of fish
- Cestoda-the bulk of a typical cestode body consists of a series of linearly arranged reproductive segments called proglottids

Important Anatomical Characteristics
- no body cavity other than the gut, and lack an anus; the same pharyngeal opening both takes in food and expels waste, breathe by diffusion, no cell can be too far from the outside, making a flattened shape necessary.

Important life cycles within groups
- reproduce sexually and disperse via eggs, Life cycles may be direct, or have 1, 2, or 3 intermediate hosts. Autoinfection is possible for some species. Adults are usually parasites of vertebrate animals, while larval forms may be free-living or infect vertebrates or invertebrates. Some parasitic larval forms are capable of asexual proliferation. Life cycles may involve aquatic or terrestrial hosts, or both.

]]> 2017-10-24 15:30:32 UTC https://padlet.com/mikelgarcia6/mjhv9f8i0ef7/wish/200046563 Annelida mikelgarcia6 https://padlet.com/mikelgarcia6/mjhv9f8i0ef7/wish/200046689 Embryological Developmental Characteristics
- bilaterally symmetrical animals that range in size from much less than 1 mm in length to more than 3 m. They have a brain or cerebral ganglion that originates and usually resides in the head. There are six major kinds of sensory structures found in annelids including palps, antennae, eyes, statocysts, nuchal organs and lateral organs. They have a closed circulatory system.

Major Groups within phyla and Distinction of how groups are different
- Polychaeta- marine annelids;
- Class Oligochaeta- marine, freshwater and terrestrial annelids including earthworms;
- Hirudinea- marine, fresh water and terrestrial leeches.

Important Anatomical Characteristics
- have a fluid-filled cavity between the outer body wall and the gut, and this is referred to as a coelom, have a body covered by an external cuticle that is never shed or molted

Important life cycles within groups
- Some annelids reproduce asexually and others reproduce sexually, but some do both
- Many annelids have both the female reproductive system and the male reproductive system or they change throughout their lives
- Some breed only once in their lives while others breed continuously throughout their lives and they all hatch as miniature adults rather than larvae

]]> 2017-10-24 15:30:45 UTC https://padlet.com/mikelgarcia6/mjhv9f8i0ef7/wish/200046689 Mollusca mikelgarcia6 https://padlet.com/mikelgarcia6/mjhv9f8i0ef7/wish/200046738 Embryological Developmental Characteristics
- They usually show bilateral symmetry, but some adults may become asymmetrical. Nervous system consists of cerebral, visceral, pleural and pedal ganglia.They are oviparous. The development is either direct or indirect (metamorphosis). When the development is indirect it includes a characteristic larva, liger, trochophore or glochidium. Asexual reproduction is absent. Some are hermaphrodite .

Major Groups within phyla and Distinction of how groups are different
(several groups, but only 3 major)
- the Gastropods- made up mostly of snails and slugs.
- the Bivalves- a group including clams, scallops, mussels, and oysters.
- the Cephalopods- a group including octopus and squid.

Important Anatomical Characteristics
- The upper surface of molluscs is covered by a shell formed by the secretions of mantle. - A muscular foot is present on underside of the body.
- The mantle cavity is a body part of molluscs formed by the fold produced in the mantle
- The different organs present in the mantle cavity include the reproductive organs, gills, kidneys and the anus. The anus is formed of chemical sensors.

Important life cycles within groups
- The life cycle of the squid varies among species, however, that of most squid follows a similar pattern. Female squid spawn, leaving fertilized eggs in the water. Depending upon environmental conditions, the eggs hatch within about two weeks. Larvae emerge.

]]> 2017-10-24 15:30:50 UTC https://padlet.com/mikelgarcia6/mjhv9f8i0ef7/wish/200046738 Arthropoda mikelgarcia6 https://padlet.com/mikelgarcia6/mjhv9f8i0ef7/wish/200046893 Embryological Developmental Characteristics
- land, sea and air, and make up over three-fourths of all currently known living and fossil organisms, they produce a hard exoskeleton made of chitin, a mixture of lipids, carbohydrates and protein, which covers and protects their bodies like a suit of armor. They have jointed limbs attached to their hard exoskeletons that allow for flexibility and movement. They have bilateral symmetry and have an open circulatory system.

Major Groups within phyla and Distinction of how groups are different
- Chelicerates- spiders, mites, ticks, scorpions, and horseshoe crabs
- Trilobites- extinct
- Crustaceans- lobsters, crabs, and shrimp
- Uniramians- millipedes, centipedes, and the most numerous group of all, the insects

Important Anatomical Characteristics
- have a stiff cuticle made largely of chitin and proteins, forming an exoskeleton that may or may not be further stiffened with calcium carbonate
- have segmented bodies and show various patterns of segment fusion to form integrated units

Important life cycles within groups
- larva and pupa stages and the process of metamorphosis
- Arthropods reproduce sexually. Male and female adults produce gametes. If fertilization occurs, eggs hatch into offspring.]]> 2017-10-24 15:31:00 UTC https://padlet.com/mikelgarcia6/mjhv9f8i0ef7/wish/200046893 Echinodermata mikelgarcia6 https://padlet.com/mikelgarcia6/mjhv9f8i0ef7/wish/200046952 Embryological Developmental Characteristics
- radial symmetry, several arms (5 or more) radiating from a central body. The body actually consists of five equal segments, each containing a duplicate set of various internal organs. They are metazoa animals (multi-celled). These are exclusively marine that are triploblastic and adults are radially symmetrical while the larvae are bilaterally symmetrical and they are coelomate.

Major Groups within phyla and Distinction of how groups are different
- Asteroidea- sea stars
- Ophiuroidea - brittle stars
- Echinoidea - sea urchins and sand dollars
- Crinoidea - sea lilies or feather stars
- Holothuroidea- sea cucumbers

Important Anatomical Characteristics
- The body actually consists of five equal segments, each containing a duplicate set of various internal organs. They have tentacle-like structures called tube feet with suction pads situated at their extremities. They can regenerate missing limbs, arms, spines and intestines
-Heart is absent, Blood has no pigment, Digestive system is complete, Excretory system is absent

Important life cycles within groups
-Reproduction is carried out by the release of sperm and eggs into the water. Most species produce free floating planktonic larvae which feed on plankton. These larvae are bilaterally symmetrical, unlike their parents. When they settle to the bottom they change to the typical echinoderm features.

]]> 2017-10-24 15:31:07 UTC https://padlet.com/mikelgarcia6/mjhv9f8i0ef7/wish/200046952 Chordata mikelgarcia6 https://padlet.com/mikelgarcia6/mjhv9f8i0ef7/wish/200047118 Embryological Developmental Characteristics
They are deuterostomes, as during the embryo development stage the anus forms before the mouth. They are also bilaterally symmetric coelomates. They have a fluid filled body cavity.

Major Groups within phyla and Distinction of how groups are different
tunicates and lancelets- invertebrate chordates

hagfish and lamprey- jawless vetebrates having mainly just a simple skull

chondrichthyes- have cartilaginous skeleton and a 2-chambered heart; lacks a swim bladder

osteichthyes- bony skeleton and have a swim bladder and 2-chambered heart

amphibians- adults live on land but must return to water to reproduce or develop; have moist skin for breathing

reptiles- have scaly skin, lay eggs with leathery shell and are ectothermic; known amniotes with 3 or 4 chambered heart

birds- have feathers, are endotherms; known amniotes with 4-chambered heart; air sacs, crop and gizzard

mammals- amniotes having hair and mammary glands; also have 4-chambered heart, diaphragm, and lungs; endothermic

monotremes- egg-laying mammal; has many reptilian characteristics

marsupials- mammals whose young develop in a pouch

eutherians- mammals that give live birth; baby attached to a placenta

primates- mammals that can grasp with their hands and have great depth perception

hominids- mammals that walk on two legs (bipedalism) and have a large brain compared to its body weight

Important Anatomical Characteristics

- notochord- a flexible, rod-shaped structure that is found in the embryonic stage of all chordates and also in the adult stage of some chordate species.
- dorsal hollow nerve cord- derives from ectoderm that rolls into a hollow tube during development
- pharyngeal slits- are openings in the region just posterior to the mouth that extend to the outside environment.
- post-anal tail- a posterior elongation of the body, extending beyond the anus

Important life cycles within groups
-begins with fertilization. In its primitive form, fertilization occurs externally, in the water
- Asexual reproduction takes place in tunicates and in some vertebrates.
- Hermaphroditism is found in tunicates and some fishes, but otherwise the sexes are separate.
- When larvae occurs, they differ in structure from the larvae of nonchordates.
- Internal fertilization and parental care are common in tunicates and vertebrates.

]]> 2017-10-24 15:31:25 UTC https://padlet.com/mikelgarcia6/mjhv9f8i0ef7/wish/200047118 mikelgarcia6 https://padlet.com/mikelgarcia6/mjhv9f8i0ef7/wish/207758545 2017-11-16 16:30:22 UTC https://padlet.com/mikelgarcia6/mjhv9f8i0ef7/wish/207758545 mikelgarcia6 https://padlet.com/mikelgarcia6/mjhv9f8i0ef7/wish/207760996 Acoelomates lack a coelom (do not have a true body cavity.) It is usually filled with cells. Pseudocoelomate has the beginnings of a body cavity, but lacks mesentery (or peritoneum). Coelomate animals have a "true" body cavity or coelom and organs are incased in peritoneal membrane.]]> 2017-11-16 16:34:16 UTC https://padlet.com/mikelgarcia6/mjhv9f8i0ef7/wish/207760996