Biol 121 A Final exam Chapter 6-8

Ostia are small pores in sponges that allow water to enter the sponge's body.

Oscula are large openings in sponges through which water exits after circulating through the sponge's body.

The spongocoel is the central cavity within a sponge, where water flows through and is filtered for nutrients.

Mesohyl is the gelatinous, non-cellular layer found between the outer and inner cell layers of a sponge. It provides structural support and contains various cells involved in the sponge's functions.

Pinacocytes: These cells form the outer layer of the sponge and help regulate the flow of water.

Porocytes: These tubular cells create pores (ostia) through which water enters the sponge.

Archaeocytes: Also known as amoebocytes, these versatile cells can transform into other cell types and are involved in digestion, reproduction, and repair.

Sclerocytes: These cells produce spicules, which are structural elements that provide support and deter predators.

Spongocytes: These cells produce spongin fibers, which contribute to the sponge's flexible skeleton.

Choanocytes: Also known as collar cells, these cells have flagella that create water currents and trap food particles for digestion.

Pinacocytes: These cells form the outer layer of the sponge and help regulate the flow of water.

Porocytes: These tubular cells create pores (ostia) through which water enters the sponge.

Archaeocytes: Also known as amoebocytes, these versatile cells can transform into other cell types and are involved in digestion, reproduction, and repair.

Sclerocytes: These cells produce spicules, which are structural elements that provide support and deter predators.

Spongocytes: These cells produce spongin fibers, which contribute to the sponge's flexible skeleton.

Choanocytes: Also known as collar cells, these cells have flagella that create water currents and trap food particles for digestion.

Spicules are structural elements found in sponges. They provide support and deter predators. Spicules can be made of silica, calcium carbonate, or spongin, and they come in various shapes and sizes.

Ascon is the simplest body form of sponges.

Sycon is a more complex sponge body form than ascon. It features a tubular shape with thicker walls that have radial canals lined with choanocytes.

Leucon is the most complex sponge body form. It features a network of chambers and canals lined with choanocytes, allowing for efficient water flow and filtration. This structure provides a larger surface area for feeding and gas exchange compared to ascon and sycon forms.

Calcarea is a class of sponges characterized by their calcium carbonate spicules. These sponges typically have simple body structures and are found in marine environments. They can exhibit ascon, sycon, or leucon body forms.

Demospongiae is the largest class of sponges, comprising about 90% of all sponge species. They have a skeleton made of spongin fibers, silica spicules, or both. These sponges can exhibit a variety of body forms.

Hexactinellida, also known as glass sponges, are a class of sponges characterized by their silica-based spicules

Homoscleromorpha is a class of sponges characterized by their simple structure and lack of spicules or with small, simple spicules. They are found in marine environments and have a unique type of collagen called Homoscleromorpha in their tissues.

A polyp is a cylindrical, sessile form found in cnidarians, with a mouth surrounded by tentacles at one end.

A medusa is a free-swimming, umbrella-shaped form found in cnidarians, like jellyfish.

Radial symmetry is when an organism can be divided into similar halves by multiple planes through the central axis.

The epidermis is the outermost layer of cells in an organism, providing protection and covering. In cnidarians, it contains specialized cells like cnidocytes for defense and capturing prey.

The gastrodermis is the inner layer of cells in cnidarians, lining the digestive cavity and aiding in digestion and nutrient absorption.

Mesoglea is the gelatinous layer found between the epidermis and gastrodermis in cnidarians, such as jellyfish and sea anemones. It provides structural support and helps maintain the shape of the organism.

Cnidocytes are specialized cells found in cnidarians, such as jellyfish, corals, and sea anemones. These cells contain stinging organelles called nematocysts, which are used for defense and capturing prey.

Cnidae are specialized organelles found within cnidocytes, the stinging cells of cnidarians. They contain the nematocysts

Nematocysts are specialized stinging organelles found within cnidocytes in cnidarians. They are used for defense and capturing prey by delivering toxins when triggered.

Scyphozoa, also known as true jellyfish, is a class of cnidarians characterized by their dominant medusa stage. They have a bell-shaped body with tentacles and are primarily marine organisms. Scyphozoans are known for their pulsating movements and can range in size from small to very large.

Hydrozoa is a class of cnidarians that includes a wide variety of species, such as hydras, Portuguese man o' war, and many colonial species. They can exhibit both polyp and medusa forms in their life cycle. Hydrozoans are found in both marine and freshwater environments and are known for their diverse and complex life histories.

Cubozoa, also known as box jellies, are a class of cnidarians characterized by their cube-shaped medusa form. They are known for their potent venom and complex eyes. Box jellies are primarily found in tropical and subtropical oceans and are capable of strong, directional swimming.

Anthozoa is a class of cnidarians that includes corals, and sea anemones. Unlike other cnidarians, Anthozoans do not have a medusa stage in their life cycle. They are exclusively polypoid and are known for their ability to form complex and diverse reef structures in marine environments.

The manubrium is a tubular structure in cnidarians, such as jellyfish, that hangs down from the center of the bell and contains the mouth at its tip. It plays a key role in feeding by capturing and ingesting prey.

Gastric filaments are thread-like structures found in the gastric pouches of some cnidarians, such as jellyfish. They contain nematocysts and gland cells that aid in digestion and help subdue prey.

Gastric pouches are compartments within the digestive cavity of some cnidarians, such as jellyfish. They aid in digestion and nutrient absorption, often containing gastric filaments that help subdue prey and break down food.

The velum is a membrane found in some cnidarians, such as hydrozoan medusae. It extends inward from the edge of the bell, helping to increase swimming efficiency by narrowing the opening through which water is expelled.

A zooid is an individual animal that is part of a colonial organism. Each zooid functions as a separate unit but is connected to other zooids in the colony, sharing resources and contributing to the overall survival and function of the colony. Examples include the polyps in coral colonies and the individual units in a Portuguese man o' war.

A gastrozooid is a specialized feeding zooid found in colonial cnidarians, such as hydrozoans. It is responsible for capturing and digesting food, providing nutrients to the entire colony.

A gonozooid is a specialized reproductive zooid found in colonial cnidarians, such as hydrozoans. It is responsible for producing and releasing gametes, contributing to the sexual reproduction of the colony.

A dactylozooid is a specialized defensive zooid found in colonial cnidarians, such as hydrozoans. It is equipped with numerous cnidocytes and is responsible for protecting the colony from predators and capturing prey.

Siphonophores are a group of colonial marine cnidarians belonging to the order Siphonophorae. They are composed of specialized individual animals called zooids, which are morphologically and functionally distinct but physiologically integrated. Each zooid performs a specific role, such as feeding, reproduction, or defense, contributing to the overall function and survival of the colony. One of the most well-known siphonophores is the Portuguese man o' war.

Hydrocorals are a group of colonial marine cnidarians belonging to the class Hydrozoa. They resemble true corals and form calcium carbonate skeletons, contributing to reef structures. Unlike true corals, hydrocorals have a more complex life cycle that includes both polyp and medusa stages. One well-known example of hydrocorals is the fire coral, which can deliver a painful sting.

Colloblasts are specialized cells found in ctenophores, also known as comb jellies. These cells are used for capturing prey by releasing a sticky substance that helps the ctenophore adhere to its target. Unlike cnidocytes in cnidarians, colloblasts do not sting but instead rely on their adhesive properties to secure prey.

Bilateria are animals with bilateral symmetry, meaning their body can be divided into mirror-image halves along a single plane. They typically have three germ layers and exhibit cephalization, where sensory organs and nerve cells are concentrated at the front end of the body.

Deuterostomes

Protostomes

Ecdysozoa is a major group of protostome animals that includes arthropods (like insects, spiders, and crustaceans) and nematodes (roundworms). They are characterized by their ability to molt, or shed their exoskeleton, as they grow. This process is called ecdysis.

Lophotrochozoa is a major group of protostome animals that includes diverse phyla such as mollusks, annelids, and flatworms. They are characterized by either a lophophore, a crown of ciliated tentacles used for feeding, or a trochophore larval stage. This group exhibits a wide range of body forms and life histories.

Cephalization is the concentration of sensory organs and nerve cells at the front end of an animal's body, forming a head region.

Parenchyma is the functional tissue of organs in animals, such as the liver or lungs. It consists of cells that perform the specific functions of the organ, as opposed to the connective or supporting tissue.

Protonephridia are excretory structures found in some invertebrates, such as flatworms. They consist of a network of tubules with specialized cells called flame cells that help filter and remove waste from the body.

A flame cell is a specialized excretory cell found in some invertebrates, such as flatworms. It helps in the removal of waste and excess water from the body through a network of tubules.

An excretory canal is a tubular structure in some invertebrates, such as nematodes, that helps remove waste products from the body.

Cerebral ganglia are clusters of nerve cells found in the head region of some invertebrates, such as annelids and arthropods. They act as a simple brain, coordinating sensory input and motor output for the organism.

Simultaneous hermaphroditism is when an organism has both male and female reproductive organs at the same time, allowing it to produce both eggs and sperm.

Turbellaria is a class of flatworms within the phylum Platyhelminthes. These organisms are mostly free-living and can be found in a variety of aquatic and terrestrial environments.

Trematoda, also known as flukes, is a class of parasitic flatworms within the phylum Platyhelminthes. These organisms are endoparasites, meaning they live inside their hosts. They have complex life cycles that often involve multiple hosts, including snails and vertebrates. Trematodes are known for their flattened, leaf-like bodies and are responsible for various diseases in humans and animals, such as schistosomiasis.

Monogenea is a class of parasitic flatworms within the phylum Platyhelminthes. These organisms are ectoparasites, meaning they live on the external surfaces of their hosts, typically fish. Monogeneans have a direct life cycle, usually involving only one host, and are known for their specialized attachment organs called haptors, which help them cling to their hosts.

Cestoda, also known as tapeworms, is a class of parasitic flatworms within the phylum Platyhelminthes. These organisms are endoparasites, meaning they live inside their hosts. Tapeworms have a complex life cycle that often involves multiple hosts, including vertebrates. They are known for their long, ribbon-like bodies, which are divided into segments called proglottids. Tapeworms attach to the intestinal walls of their hosts using a specialized structure called a scolex.

A scolex is the head-like structure of a tapeworm (Cestoda). It is equipped with hooks and suckers that allow the tapeworm to attach to the intestinal wall of its host. The scolex is essential for the parasite's ability to remain anchored and absorb nutrients from the host's digestive system.

In tapeworms (Cestoda), the neck is the region just behind the scolex (head). It is responsible for producing new segments called proglottids, which make up the body of the tapeworm. The neck continuously generates these segments, allowing the tapeworm to grow in length.

Proglottids are the segments that make up the body of a tapeworm (Cestoda). Each proglottid contains reproductive organs, allowing the tapeworm to produce eggs. As new proglottids are formed in the neck region, older ones move towards the end of the tapeworm and eventually break off, releasing eggs into the host's digestive system.

Endoparasites live inside their host's body, such as tapeworms in the intestines. Ectoparasites live on the surface of their host, like lice on the skin.

A haptor is a specialized attachment organ found in monogenean parasites. It is used to anchor the parasite to the external surface of its host, typically fish. The haptor is equipped with hooks, clamps, or suckers that help the parasite cling tightly to its host.

A prohaptor is a complex anterior attachment organ found in monogenean parasites. It is used for feeding and attachment, helping the parasite anchor itself to the host while the primary attachment organ, the opisthaptor, is being repositioned.

Trophi are the jaw-like structures found in the pharynx of rotifers, a group of microscopic aquatic animals. These structures are used for grinding and processing food, playing a crucial role in the feeding mechanism of rotifers.

The mastax is a muscular pharynx found in rotifers, a group of microscopic aquatic animals. It contains the trophi, which are jaw-like structures used for grinding and processing food. The mastax plays a crucial role in the feeding mechanism of rotifers.

Eutely is a condition in which an organism has a fixed number of cells in its body throughout its life. This means that growth occurs by cell enlargement rather than cell division. It is commonly observed in some invertebrates, such as nematodes and rotifers.

Syncytial refers to a type of tissue organization where multiple nuclei share a common cytoplasm without being separated by individual cell membranes. This can occur through the fusion of cells or by nuclear division without subsequent cell division. Syncytial structures are found in various organisms, including some invertebrates and certain stages of embryonic development in animals.

Animal is ONE CELL WHICH CONTAINS MANY NUCLEI

In rotifers, "toes" refer to the structures at the posterior end of their bodies that help them attach to surfaces. These toes are part of the rotifer's pedal glands, which secrete adhesive substances. This allows rotifers to anchor themselves securely in their aquatic environments, aiding in their stability and movement.

Pedal glands in rotifers are specialized glands that produce adhesive substances. These secretions allow rotifers to attach to surfaces, aiding in their movement and stability in their aquatic environments.