WFSC 335 - Exam #1

Hypolimnion

A region at the bottom of the lake that is poorly illuminated, denser, and colder water where wind action has no substantial effect.

Ostium

A small incurrent opening of a sponge.

Prosopyle

A small intercellular space preceding the canal system of sycenoid and leuconoid sponges.

Spicule

A small supportive spike-like structure found in sponge skeletons.

Organelle

A specialized membrane-bound part in a protozoan that performs some special function.

Amphiblastula

A sponge larva with anterior, externally flagellated micromeres and posterior marcomeres.

Mesoderm

A term applied to all cells, cell layers, or cell masses which occur in the embryo between the ectoderm and endoderm. Third germ layer.

Porocyte

A tubular epidermal cell that surrounds an osmium in sponges.

Archeocyte

A wander cell capable of differentiating into any of several cell types in sponges.

Terrestrial organisms and their eggs

A. Many terrestrial organisms lay eggs, oviparous, which have outer coverings and specialized inner membranes surrounding the embryo to prevent desiccation. B. Eggs generally develop further in terrestrial forms and in many cases development of larval stage is eliminated or occurs within the egg for protection. C. These eggs must store water, salt nutrients, and waste products that accumulate (cleidoic).

Terrestrial Environments

A. Probably the most variable situation that animals & plants face. B. Moisture is a very limiting factor & dehydration is a problem. C. Temperature tends to be much more variable and has much wider ranges. D. The environment circulates quite rapidly and there is a relatively uniform distribution of oxygen and carbon dioxide. E. Although soil provides solid support, air does not so that a strong support system, such as a skeleton, is needed. F. Locomotion requires specializations such as legs. G. Environment is not continuous.

True mesoderm

All mesoderm which arises from the endoderm.

___________ are able to change their body morphology

Amoebas

Amoebocyte

An amoeboid wandering cell found in sponges.

Mitochondrium

An organelle which contains the enzymes of respiration (TCA Cycle, oxidative phosphorylation). Characteristically these have crust present which are a complex forced network to provide surface area for respiration reactions.

Plastids

Any of several forms of a self-replication semi-autonomous "plant" cell organelle, a chloroplast specialized for photosynthesis, a chromoplast specialized for pigmentation, or a leucoplast specialized for starch storage.

Most groups within the Animal Kingdom are thought to have originated in _________ __________, before fossil records.

Archeozoic Oceans

Heterospecific (Interspecific)

Associations between members of different species. 1) Predator-prey associations 2) Competition: habitat selection, food, etc. Less common. 3) Symbiosis: Commensalism, Mutualism, & Parasitism

Homospecific (Intraspecific)

Associations between members of the same species. 1) Competition: for things such as habitat selection, food, mates, etc. 2) Peck orders 3) Social behavior: wasps, bees, etc.

Animals go from ______ --> ________

Asymmetry --> Symmetry

Sessile

Attached to a substrate.

The idea of phylogeny

Based on the evolution of a genetically related group of organisms as distinguished from the development of individual organisms, and the approach provides the basis for studying the evolution of invertebrates and their classification.

___________ may be located centrally, or displaced toward the animal pole.

Blastocoel *These hollow blastulae are termed oceloblastulae; other blastulae are solid without a blastocoel and are termed stereoblastulae and arise from some homolecitahl and telolecithal eggs.

Acoelomate

Blastocoel fills up with mesoderm in form of muscle fibers, parenchyma, and other tissues. The digestive cavity remains.

Pyrenoids

Bodies associated with chromatophores which appear to function in starch formation.

What do the Kingdom Bacteria and the Kingdom Archaea have in common?

Both have no nucleus or organelles, but have double strands of DNA in either single, circular, or linear chromosomes.

Paramylon & Leucosin

Carbohydrate storage products in protozoans.

Archaea

Composed of microorganisms that possess unique genes, metabolic pathways, and other biochemical processes from Bacteria

Microsome

Concentration of enzymes for protein synthesis in area ribosomes or endoplasmic reticulum.

Sexual (gametic)

Conjugation, anisogamy (usually motile and different sizes), isogamy (usually motile and similar sizes). *More rarely, oogamy (large female, non-motile gamete and small, motile male gamete)

Autotrophic

Create their own food; photosynthetic.

Saprotrophic

Digestion and absorption of nutrients as in decaying of organic materials by fungi or bacteria.

Some groups such as _________ and ______ are almost entirely marine.

Echinoderms (starfish), Cnidarians (jellyfish)

Gastrulation results in two germ layers: ________ and _________.

Ectoderm; Endoderm. *If a gastrocoel is present it is the primoridum of the digestive tract and the blastopore may be the embryonic mouth.

Superficial Cleavage

Equal cleavage where the yolk material are surrounded. It is seen in some centrolecithal.

Pseudocoelomate

False Coelom; blastocoel persists in adults leaving a space between the digestive tract and the body wall. The mesoderm separates from the endoderm and connects to the body wall in the form of longitudinal muscles and connective tissue.

Radial Symmetry (Cylindrical, Subspherical)

From a top or bottom view would appear much like a spherical symmetry. Cannot cut the organisms at their "waist". *Ex: Jellyfish, anemones, corals, cnidarians *Most organisms are sessile & the diameter of the top is rarely the same as the diameter of the bottom *Others are active swimmers or floaters

Bilateria

Generally have internal organs and will have some form of fluid-filled cavity lying between the body wall and the internal organs, the body cavity or coelom. *Can further break down by having a true body cavity, a false body cavity, or no body cavity.

The Filosea

Group that contains rapidly forming filopodia, including the testate and atestate species Euglypha, Gromia, and Vampyrella.

Radiata

Have few or no organs, cellular differentiation is generally minimal. *Sponges, Cnidarians, and Ctenophores

Why are bodies becoming more and more organized around a central plane beneficial?

Helps with central nervous systems and organ systems to be divided more easily and you can have more structure within the cells.

Mesotrophic

In between Eutrophic & Oligotrophic.

What is the mechanism aquatic organisms use when extreme temperatures conditions occur?

In extreme temperature conditions or where freshwater systems dry up, many aquatic organisms form resistant stages such as the gemmules of fresh water sponges, the cysts of protozoans, and the statoblasts of bryozoans.

Indeterminate Cleavage

In species of animals which have this type of cleavage, such as Echinodermata and Hemichordata, the embryonic fate of blastomeres is not determined until relatively late in the embryological development. *Characteristic of those organisms placed in the Deuterostomes.

Spiral Cleavage

In these micrometers rotate 45 degrees from vertical after the third cleavage. After this rotation, successive tiers of blastomeres alternate so that cells of one tier rest in the wells or cell spaces formed between the cells below them. *The shifting of cells may be dystrophic (counterclockwise) in some groups or levotrophic (clockwise) in others.

Succession

In transition from Oligotrophic to Eutrophic.

Holotrophic

Ingesting other organisms.

What type of environment is radial symmetry most seen in?

It has been suggested that in an evolutionary sense, the development of this type of symmetry implies a rather uniform environment where biotic stresses are equally distributed. Some Porifera, Cnidaria, and Echinodermata display this type of symmetry, but generally it is seen in marine organisms. *Echinoderms are bilaterally symmetric as larvae, but turn radially symmetric when adults.

Amictic

Lakes that do not experience turnover phenomena.

Holomictic

Lakes that experience complete mixing or turnover events.

Polymictic

Lakes that will turn over more than twice a year.

Monomictic

Lakes that will turnover once each year.

Eutrophic

Lakes which are relatively shallow, warm, rich in organic matter and nutrients, and consequently highly productive. Because of the heavy accumulation of organic matter, oxygen depletion in the hypolimnion generally occurs during summer.

Oligotrophic

Lakes which are relatively young, deep, cold, & non-productive. Characterized by: 1) Low frequency of nutrient recycling. 2) Relatively low levels of phosphorus, nitrogen, and calcium.

Bacteria

Large kingdom of prokaryotic organisms that contains most known bacteria

Stigma

Light-perceiving organelle in photosynthetic flagellates and a few colorless species usually contains a reddish pigment.

Meiofauna (Interstitial Fauna)

Many species of invertebrates that live in the spaces between sand grains.

Today, every major phylum of animals has at least one __________ representative.

Marine

Phylum Ciliophora Class Oligohymenophora

Members of this class have the oral apparatus well developed with compound ciliary organelles present (cirri).

Food Vacuole

Membrane-bounded organelle involved in the digestion of food particles.

Ectomesoderm

Mesenchymal (connective tissue-like network) consists of "inwardering" ectoderm cells. Present in Radiate and Protostomia.

What is another problem in regards to the invasion of terrestrial environments?

Mode of respiration - gills which served so effectively in an aqueous medium like water were not effective in air and therefore only those organisms with more functional organs like trachea, lungs, or other specialized respiratory surfaces could adapt.

Zooflaggelates

More animal-like in that they lack chlorophyll or other pigments. These have one to many flagella and either holozoic or saprozoic.

Filopodia

More slender, pointed, sometimes branched pseudopodia formed from ectoplasm only.

Deuterostomata

Mouth does not arise from blastopore. 1) Echinodermata 2) Chaetognatha 3) Hemichordata 4) Chordata

Cytostome

Mouth-like structure which is responsible for taking materials into the cytoplasm of some protozoans.

Lotic Systems

Moving bodies of fresh water such as streams or rivers.

Animals (Metazoa)

Multicellular animals including Parazoa (sponges) and other metazoan animals.

Plants (Metaphyta)

Multicellular plants including vascular and non-vascular forms. Some authors place algae in this Kingdom.

Spherical Symmetry

No matter which direction the plane of symmetry dissects the organism, the two halves will be identical. A few planktonic Protozoa (marine & freshwater) exhibit this configuration. *RARE

Commensalism

One organism benefits, the host is neither harmed nor benefits. "Eating at the same table."

Pelagic Organism

Organisms that are either suspended in the water column or are swimmers.

Besides respiration, exoskeletons, and internal skeletons, what were some other major obstacles in regards to the invasion of land?

Osmotic balance, salt retention, and water retention. *Availability of salt and prevention of dehydration required thicker, more effective outer coverings and also better more efficient excretory systems in both adults and larval forms. *In aqueous surroundings nitrogenous waste products could be excreted in the form of ammonia, but on land such waste products are often in the form of urea which is suspending in water, stored and voided, and solidified as uric acid and discharged.

Incurrent Canal

Passageway through the external cortex which preceds the prosopyles of advanced sponges.

Nucleus

Prominent membrane-bound sac containing the chromosomes and providing physical separation between transcription and translation. The term karyosome can be used interchangeably.

Benthic

Refers to the bottom region or substrate which supports "benthic" communities. The intertidal would have a benthic, would the sublittoral and continental slope.

Cyst

Resting stage of a protozoan for protection against the environment. Sometimes reproduction and regeneration or nuclear reorganization may occur in the cyst.

Protostomata

Retain blastopore as mouth. 1) Platyhelminthes 2) Nemertea 3) Acanthocephala (no mouth) 4) Entoprocta 5) Rotifera 6) Gastrotricha 7) Kinoryhncha 8) Nematoda 9) Tarigrada 10) Pentastomida 11) Nemtomorpha 12) Phorinida 13) Ectoprocta 14) Brachiopoda 15) Sipunculida 16) Mollusca 17) Echiuroidea 18) Annelida 19) Onychophora 20) Arthropoda

Golgi Bodies

Sac-like areas of lipid phosphorous and enzymes concentrations. It is responsible for secretion and packaging of certain materials for distribution into the cytoplasm of the cell.

Atrium

Same as spongocoel.

Coelomate

Secondary body cavity. This is a cavity in the endomesoderm. *Schizocoel: as the mesoderm develops, the coelom develops as a split in the mesoderm (most Protostomia).

Protista

Simple, single-celled eukaryotes such as protozoans

Unicellular (Acellular)

Single celled organisms that carry out the same basic functions as multicellular organisms without having specialized cells organized into tissues and organs.

Ovoviviparous

Some land dwelling invertebrates retain eggs within their uterus until they hatch and then release larvae (larva position), instead of laying eggs.

Why did reproduction pose a problem when the invasion of terrestrial environments occurred?

Sperm no longer had a surrounding aqueous medium for transport and direct delivery was more effective. *Specialized structures are commonly found in many terrestrial breeders for internal fertilization and sperm delivery. *Some organisms still retain the ability to return to water for reproduction purposes.

Lentic Systems

Standing bodies of fresh water such as ponds and lakes.

Asexual (agametic)

Symmetrogenic binary fission, cysts, schizogony (multiple fission), budding.

Eggs of freshwater aquatic organisms

Tend to be larger and, in addition to storing food for larval development and waste products, they must also accommodate the store of salt.

Mutualism

The "parasite" and the host both benefit

Protoplasm

The bulk of protozoan which includes cytoplasm where catabolism occurs and the nucleus where anabolism occurs.

Cytoplasm

The colloidal region which is found between the nuclear membrane and the plasma membrane. This region is composed primarily of protein and can, in general, be divided into two regions.

Ectoplasm

The cortical layer of protein and lipoprotein fibers which is generally in a gel state which forms the outer periphery of the protozoan.

Tropholytic Zone

The deeper zone of water below the Trophogonic Zone and essentially encompasses a depth equivalent to the Sublittoral Zone and the Profundal Zone. It is similar to the Aphotic Zone of oceans, in that it is defined as the deeper zone where light can not effectively penetrate and respiration exceeds photosynthesis.

Speciation

The division of a species into two or more species over time.

Intertidal or Littoral Zone

The edge of the sea which rises and falls with the tides.

Holoblastic Cleavage

The entire embryological mass divides including the yolk. This is characteristic of homolecithal eggs and is most common mode of cleavage in the metazoan phyla. Blastomeres are generally equal in size and evenly distributed around the forming embryonic cavity, the blastocoel.

Apopyle

The excurrent opening of a choanocyte chamber in leuconoid sponges.

Endoplasm

The inner medullary region which is typically in a solid state and contains all the basic organelles. This region is surrounded by the ectoplasm.

Infauna

The invertebrates living beneath the surface of the bottom substrate.

Epifauna

The invertebrates living on the surface of the bottom substrate.

Osculum

The large excurrent opening of a sponge.

Parenchymella

The larva form of a leuconoid sponge.

Abyssal Zone

The lowest portion of the continental slope which generally forms the ocean bottom.

Spongocoel

The main interior body cavity of a simple sponge.

Enterocoel

The mesoderm arises as out pockets from the primitive gut (archenteron). These pockets become cut off in the blastocoel; their cavity is the coelom, their walls the mesoderm (Deuterostomia).

Homolecithal/Isolecithal Eggs

The ovum contains evenly distributed yolk as is typical of the mollusks.

Parasitism

The parasite benefits, the host is harmed.

Subtidal or Sublittoral Zone

The region below the Intertidal Zone which extends outward to the end of the continental shelf.

Supratidal or Supralittoral Zone

The region just above the intertidal zone.

Neritic Zone

The region of ocean that covers the continental shelf.

Oceanic Zone

The region of the ocean that is beyond the continental shelf.

Bathyal Zone

The region of the stub tidal that slopes off toward the bottom of the Abyssal Zone.

Bathypelagic

The region of the water column between 1,000 meters and 4,000 meters in depth.

Mesopelagic

The region of the water column between 200 meters and 1,000 meters in depth.

Epipelagic

The region of the water column between the surface and 200 meters in depth. Because of the depth, the region is generally found outside the sublittoral zone.

Abyssopelagic

The region of the water column deeper than 4,000 meters.

Aphotic

The region of the water column in deeper water which is beyond the depth of light can effectively penetrate. This layer lies below the Photic Zone and is characterized by darkness. There may be a region of transition between this region and the Photic Zone.

Phylogeny

The study of the history of lines of evolution in a group of organisms.

Hadal Zone

The trench-like regions found in the ocean floor.

Epilimnion

The upper region in stratification which is characterized by being well mixed, well illuminated, and nearly isothermal.

Photic or Euphotic Zone

The upper region of the ocean where light can effectively penetrate and photosynthesis exceeds respiration. Usually between 100 and 200 meters depending on turbidity (cloudiness or haziness of a fluid).

Meroblastic Cleavage

The yolk cells do not divide so that cleavage is unequal. Generally seen in telolecithal and centrolecithal eggs.

Telolecithal Eggs

The yolk eccentrically located as is seen in Cephalopods and some arthropods. *Area without the yolk = animal pole *Area with the yolk = vegetable pole

Centrolecithal Eggs

The yolk is centrally distributed as is common in insects and some crustaceans.

Phylum Actinopoda

These are primarily planktonic floaters or in some cases sessile. All have actinopoda radiating from a spherical body.

Larval stages within the egg

These larval stages within the egg are normally hypertonic and will have a thicker more impermeable "shell" or outer coat.

Lobopodia

Thicker, blunt pseudopodia formed from endoplasm and ectoplasm.

Phylum Ciliophora Class Litostomatea

This class is characterized by having isolated kinetics (longitudinal units of cilia, basal bodies, and Kinetodesmata) in the area of oral groove bearing cilia but no compound ciliary structures like cirri.

Phylum Ciliophora Class Phyllopharyngea

This class is generally sessile, stalked, and bear tentacles on the free end. *Cilia are lacking adults, but present in free-swimming larvae, swarm cells. *This class is represented by Ephelota, Podophrya, and Acineta.

Bilateral Symmetry

This form of symmetry has a definite anterior and posterior region. If a plane is passed along the anterior-posterior axis, it will divide the organism into two equal parts such that the right & left halves are mirror images of each other. *Evolved first in the flatworms and then never left.

Littoral Zone in Lentic Systems

This is equivalent to the Littoral Zone of oceans. It is generally the peripheral shallow zone which extends from the shoreline of a lake to the depth where plants no longer are found.

Profundal Zone

This term is not typically employed in marine systems. It is the region below the sublittoral zone in deep lakes and essentially is the bottom zone.

Radial Cleavage

This type of cleavage is found in Brachiopoda, most Echinodermata, and Hemichordata. In this type of cleavage, there is a regular alteration of blastomeres around a polar axis so that cleavage planes are at right angles or parallel to the polar axis resulting in a centrally located blastocoel (homolecithal eggs).

Bilateral Cleavage

This type of cleavage is seen in Nematodes, other "Aschelminthes", and some Hemichordata. Tends to be into right and left halves.

Dissymetrical Cleavage

This type of cleavage is typical of the Ctenophora (comb jellies).

Biradial Symmetry

This type of symmetry is usually formed by the development of evenly distributed projections in association with radial symmetry giving such organisms a more bilateral appearance. *Ex: Ctenophores are jellyfish that have two tentacles or stinging combs.

Sublittoral Zone in Lentic Systems

This zone is essentially equivalent to the Sublittoral Zone of oceans. In lakes it is the zone which extends lake-ward from the Littoral Zone into deeper water.

Limentic Zone

This zone is roughly the same as the Epipelagic Zone of oceans and is sometimes referred to as the Pelagic Zone. It is the zone lake-ward from the littoral zone extending from the surface of the water to the approximate depth of the littoral zone. It is sometimes used interchangeably with the Trophogonic Zone. However, the Trophogonic Zone, like the Photic Zone of oceans is based on the depth light can effectively penetrate into the water column.

Bethos or Benthic Fauna

Those organisms living on the bottom substrate.

Phytoflagellates

Typically have one or two flagella, and are usually photosynthetic, but are often Holophytic. This plant-like group includes Euglena, Chlamydomonas, Volvox, and Peranema.

Fungi

Various fungal species including yeast, mushrooms, rusts, smuts, sac fungi, puffballs, molds, mildews, and slime molds.

Trophozoite

Vegetative, feeding and growing stage of a protozoan, often termed a "troph" for short.

Uniform environment

Water surrounding the organism.

Dystrophic Lakes

With time, some lakes may become bogs where the levels of calcium carbonate are low, humus content is high, nutrient levels are very low, & the pH is low. Generally are characterized by having brown water.

Asymmetry

Without symmetry. Many Porifera (sponges), amoeboid Protozoans, and a few other animals exhibit this.

Do freshwater lentic systems undergo wider fluctuations in temperatures than oceans?

Yes, because of their smaller size, freshwater lentic systems undergo wider fluctuations in temperatures than do oceans. Many lakes, especially deeper lakes, will undergo thermal stratification on a seasonal basis. In lakes were summer thermal stratification occurs, with the following fall turnover, three definite thermal zones are normally seen.

The development of _______ _______ is considered to have been an important step in the evolution of animals.

bilateral symmetry

The "____________" period ends with the formation of a _________, which continues its development by special morphogenetic movements called ____________.

cleavage; blastula; gastrulation

Some salt water organisms were pre-adapted and could tolerate a wider gradient of salt concentrations, ________, and because they were able to control osmotic balance they were ________ __________.

euryhaline, osmotically independent *Such organisms had the potential to move into the estuaries where the salt water is diluted by the incoming fresh water. Many of these organisms which made the transition to fresh water systems were again in a more osmotically constant environment and eventually their lineages evolved into the stenohaline, osmotically independent forms we see in fresh water systems today.

Fresh water systems tend to be significantly smaller and shallower than salt water systems and are subject to ________ ______ in temperature which must be accommodated for by fresh water organisms.

greater fluctuations

The conservation of salt in fresh water organisms is essential and therefore most fresh water organisms produce a ________ ________.

hypotonic urine *The urine is highly diluted due to the physiological activities preserving the hypertonic integrity of the body fluids of these organisms.

Many invertebrates require an almost ________ situation to exist in salt water which precludes them from moving into other environmental circumstances.

isotonic

Oceans are very large bodies of water and typically it takes relatively ________ _________ in atmospheric temperatures over _______ ________ of time to have any major effect on water temperature.

large variations; long periods

Often, the early cleavage process results in two unequal sized types of blastomeres, the large ones being the __________ and the smaller ones being the __________.

macromeres, micromeres

The single most important factor in the immigration from salt water to fresh water is probably __________.

osmoregulation

Larval forms which must be in the aquatic system also must prevent ________ ________.

osmotic imbalance *In those cases external coverings such as epithelial layers, cuticles or chitin-based exoskeletons or other structures have been evolved to limit influx of water. *Contractile vacuoles, flame cells, nephridial systems, and other specialized structures have been evolved to remove water.

Stenohaline organisms, therefore, are ____________ ___________ on the environmental circumstances found in the salt water system for their normal physiological activities.

osmotically dependent

Generally, vertebrates are _________ _________ even in salt water, but this is not true for most of the invertebrates.

osmotically independent

Most salt water organisms can tolerate only a relatively narrow range of salt concentrations and are termed _____________.

stenohaline

One general characteristic which is commonly used to evaluate the relative ancestral position of animals in the higher taxonomic categories is _____________.

symmetry

During the period of embryonic development the __________ is divided into a number of cleavage cells or ______________.

zygote; blastomeres

Determinate Cleavage

- In the normal development of many animals, such as flatworms, mollusks, and annelids, areas of developing embryo are predestined to develop into specific structures in the adult. - In this type of cleavage each blastomere has the potential for only a certain developmental pattern because they have already undergone protoplasmic differentiation. *Characteristics of those groups of invertebrates that fall into the Protostomes

Phylum Actinopoda Class Radiolaria

- Order Polycystinea have siliceous skeletons and perforated capsular membranes, and contain solitary and colonial species. (Ex: Thalassicola, Collozum, and Eucoronis) - Order Phaeodarea also have siliceous skeletons, but the capsular membrane has only three pores, and are only found in the deep sea. (Ex: Astracantha, Coelodendrum, and Phaeodina)

Protozoans (animal-like Protists)

1) A heterogenous assemblage of over 50,000 single-celled organisms consisting of several phyla. 2) Protozoa are small, one-celled eukaryotic organisms, although some are colonial. 3) The outer covering is a plasma membrane, however some may have an additional non-living outer covering called a pellicle, test or a theca. No true cell wall is present.

Schizogonic

1) A sporozite invades cells becoming the trophozoite. 2) Karyokinesis (nuclear division) which results in the release of many merozoites which re-invade other cells. 3) Some trophs may becomes the gametocytes.

Phylum Apicomplexa

1) All members of this group have an apical complex generally consisting of a polar, micronemes, rhoptries, subpelicular tubules, and conoid present at some stage. 2) Single type of nucleus present. 3) Cilia and flagella absent except for flagellated microgametes in some groups. 4) Cysts are often present. 5) All species are parasitic. 6) No cilia or flagella present in trophozoites 7) Simple spores are formed 8) Most have three stages in life cycles: Schizogonic, Gametogonic, and Sporogonic. *Used to be grouped with Microspora, but the Microspore are now thought to be fungi.

Phylum Dinoflagellata

1) Approximately 1/2 of all described marine and freshwater species are important primary producers. 2) Typcailly have two flagella, one that lies in a longitudinal groove called the sulcus and the other in a groove called the cingulum (or annulus) that runs latitudinally around the whole cell or in a spiral of several turns. 3) This group was thought to be allied with the brown algae and diatoms because of the presence of xanthophyll pigments and the absence of chlorophyll b, however, DNA evidence groups them more closely with Ciliophora and Apicomplexa. 4) "Fire plants" are so named primarily because of the color change they impart to marine systems when they become exposed to atmospheric oxygen during blooms. (Red tide which is responsible for killing large numbers of fish when it occurs in costal waters). 5) Species generally are enclosed in a thick pellicle or theca which contains cellulose. 6) Many are autotrophic, but colorless species are found to be heterotrophic and a few are both. 7) Reproduction is usually by longitudinal division, sexual reproduction is rare. Asexual zoospores are known to form in some species.

Phylum Retortamonada Class Diplomonadida

1) Bilaterally symmetrical flagellates with twice the usual number of internal and external features. 2) Species are typically oval to pear-shaped with an anterior sucking surface, or sucking disk. 3) Most structures are doubled, so that each trophozoite would have two nuclei, two axostyles, and four or more flagella. 4) These do not have an undulating membrane and there is no cytostome. 5) Giardia lamblia is probably the best known species and is the most common intestinal parasite of humans in North America. 6) There are relatively few free-living species.

General Life Cycle of Sponges

1) Budding is not common in this group although some forms, especially freshwater species, produce gemmules asexually. 2) Most sponges are hermaphroditic. 3) Certain choanocytes become spermatogonia and give rise to sperm. 4) Ova are thought to develop from either choanocytes located in the chambers, or the archeocytes located in the mesoglea (or mesohyl). 5) Sperm leave the sponge in water currents and are carried to another sponge where they are picked up by choanocytes which transport them to the ova and fertilization takes place. 6) In most species, the zygote is held in the body wall forming a parenchymella larva which breaks out, settles, and develops into the sponge. 7) Some calcareous sponges produce an amphiblastula which is somewhat motile and develops soon after the zygote is formed.

Phylum Heterolobosa

1) Cells have an inducible flagellated stage with 2-4 function flagella. 2) Lobodpodia erupt during amoeboid movement. Will encyst when in unfavorable climates. 3) Ex: Naegleria and Tetramitus 4) Naeglaria fowleri is a very dangerous pathogen of humans.

Class Homoscleromorpha

1) Composed of very primitive, simple marine sponges. These are mostly tropical and the class has relatively few species in it. 2) These tend to be leuconoid and many forms are found in shaded areas like grottos and tunnels usually in shallow water. 3) They have a very simple body type with siliceous tetractinal spicules. Most are incased in a mineral skeleton (coral-like).

The "Amoeboids"

1) Contain those animal-like species that have pseudopodia for locomotion. Although many are benthic organisms, some are also planktonic. 2) These are generally asymmetrical or spherical. 3) Some have flagellated stages. 4) Species are frequently naked, however, many have an outer covering or shell. 5) Typically have a vesicular nucleus. 6) No spores are formed in this group. 7) Sexual reproduction, if present, is syngamy or fusion of identical isogametes or dissimilar an isogametes. In these meiosis may be post-zygotes as seen in many algae. 8) Although not always obvious, they typically have an outer stiff ectoplasm and an inner more fluid endoplasm. 9) Members of this group are all holozoic with the exception of some parasitic species. 10) Reproduction is primarily by binary fission, however, multiple fission is common in multinucleate forms and heliozoans. 11) Sexual reproduction has rarely been documented for amoeba but a process where two amoeba fuse, each acting as a gamete (hologamy) has been observed for some species.

Function of germ cell layers

1) Ectoderm - epidermis and associated structures 2) Endoderm - lining of digestive tract 3) Mesoderm - cells organized into tissues and organs; lining of the body cavity.

Value of the Coelom

1) Frees digestive tract and other organs from encirclement by mesenchyme; gives space for movement, coiling, and greater activity of internal organs. 2) Furnishes a space in which nitrogenous wastes and excess water can accumulate and from which they can be discharged by excretory ducts. 3) Gonodcuts form the discharge of sex cells connect the coelem with the exterior. Gonads project into the coelom, giving ample space for the enlargement of eggs, thus the production of large yolked eggs.

Phylum Retortamonada

1) Have 2-8 flagella, some of which trails behind leading flagella and the cell bodies, and lack Golgi bodies as well as mitochondria. 2) Representative genera include Chilomastix, Retortamonas, Hexamita, and Giardia.

Phylum Axostylata

1) Have a bundle of microtubles that extends the length of the cell. In most species, it is skeletal in function, like an intracellular backbone, but in some primitive species, it undulates and imparts a snaky motion to the cell 2) Lack mitochondria, but have Golgic bodies.

The Lobosea

1) Have lobopodia 2) Ex: Acanthamoeba, Amoeba, Chaos, Entamoeba, Vannella, Arcella, and Difflugia 3) Most species in this group are naked or atestate (exceptions: Arcella & Difflugia). 4) Very common in freshwater and marine systems. 5) Probably the most common parasitic genus is Entamoeba which is generally an intestinal dweller.

Class Calcarea (Calcispongiae)

1) Have spicules composed of calcium carbonate 2) All spicules in species of this class are the same size and are monaxons or three-or-four pronged types. 3) Do not have spongin fibers. 4) Asconoid, syconoid, and leuconoid species are found in this class. 5) These tend to be somewhat smaller than members of the other three classes. 6) They are shallow water marine dwellers, represented by the genera Leucosolenia (asconoid) and Sycon (syconoid).

What are some obvious factors which immigrants must face in the transition to fresh water?

1) If the larval stages have been lost and development is primarily seen in an egg, the egg must be able to protect the larva from the fresh water environment, yet store the necessary nutrients and salt. 2) Some organisms may return to salt water to lay eggs. 3) Generally it is believed that most immigrants came from marine systems by way of estuaries. 4) Osmotic (water) balance. 5) Larger thermal gradients in fresh water. 6) Need for larval stages which are active swimmers where larval stages have been retained. 7) Ability to accommodate the reduced buoyancy in fresh water.

Gametogonic

1) Male and female gametocytes are generally picked up by the vector host during a blood meal and produce the gametes. Not all use a vector host. 2) Inside the vector these gametes will fuse to form the zygote.

Phylum Chlorophyta Order Volvocida

1) Many of these are colonial 2) Individuals are generally green, having a single cup-shaped chromoplast, a stigma, and often two to four apical flagella per cell. There are some colorless forms. 3) The group are mostly freshwater and are represented by Chlamydomonas, Polytomella, Haematococcus, Gonium, Pandorina, Platydorina, Eudorina, Pleodorina, Volvox 4) There are several forms of colonial flagellates including both sexual and asexual.

What are the two possible sources for the invasion of fresh water systems by organisms after these systems became established?

1) Marine 2) Terrestrial

Phylum Apicomplexa Class Greagrinea

1) Mature trophozoites are extracellular, generally large. 2) Paraistes in digestive tract and body cavity of invertebrates. 3) Schizogony absent, trophs become gamonts which unite in the process of Syzygy forming gametocytes and within these the two types of gametes form. 4) Life cycle with one host - specifically in echinoderms, mollusks, annelids, and especially arthropods.

Class Hexactinellida (Hyalospongiae)

1) Members of this class are the "glass" sponges. 2) The spicules of species in this class are commonly hexaxon (six-pointed). Many species have a lattice-like "skeleton" formed by the fusion of these spicules. 3) Spicules are made of siliceous fibers, thus giving the names "glass" sponges. 4) Species tend to be more symmetrical than other classes and do not form interconnecting clusters or large masses. 5) They tend to be cup-shaped, vase-like, or urn-shaped. 6) All have exposed surfaces covered with a trabecular syncytium rather than pinacoderms. 7) A syncytium also lines the chambers of the collar cells. 8) They tend to be second in general structure and are usually deep-water sponges. 9) The Venus'-flower-basket (Euplectella) is found in this class.

Phylum Euglenozoa Class Kinetoplastida

1) Members of this class characteristically have sphere, rod, or disc-shaped, self-replicating, mitochondrial-like organelle called Kinetoplast which is associated with the origin of the flagella. 2) Some species such as members of the genus Bodo are found in marine and freshwater environments and are free-living bacteria feeders. 3) Most are parasitic occurring intestinally in insets while others are extremely important blood and other tissue parasites of a variety of vertebrates including man. 4) Parasitic forms are usually passed from vertebrate host to vertebrate by a vector intermediate host which is typically blood-feeding insect. 5) Most forms have a single anterior flagellum that in some specie say be attached to the body by an undulating membrane. 6) Members of the genus Leishmania are solid tissue parasites and the intracellular stages of these lack a flagellum and are called amastigotes. *The genus Trypanosome is a blood parasite and members of the genus are responsible for African Sleeping Sickness and Chagas disease. *The trypanosomes have an undulating membrane in the blood form and is termed a trypomastigote.

Phylum Eugelnozoa

1) Monophyletic group with parasitism and commensalism having evolved independently several times, however free-living forms are most frequently encountered. 2) Have relatively thick flagella 3) Closed mitosis with an intranuclear spindle 4) Paddle-shaped 5) Discoidal mitochondrial cristae 6) Microtubule-reinforced ventral or anterior feeding apparatus 7) Tubular extrusomes

Class Demospongia (Demospongiae)

1) Most of the sponges, ~90%, are found in this class. 2) Many are quite colorful and their distribution ranges from shallow to deep water habitats. 3) In some the "skeleton" may consist of siliceous spicules or spongin or both. 4) Spicules are monoaxons or tetraxons, but not hexaxons. 5) All are leuconoid and there is a tendency to lack any real symmetry, however, there is a great variety of shapes seen. 6) This class includes the boring sponges such as those found in the genus Cliona. 7) Members of the family Spongillida are freshwater sponges and are found worldwide. 8) The common bath sponges where the "skeleton" is composed of only spongin fibers (spongin and hippospongia) are also found in this class.

Phylum Caryoblasta

1) Most primitive group of amoeboids, lacking a nucleus, mitochondria, and Gogli bodies. 2) Respiration is only possible when respiratory organelles are filled with endosymbiotic bacteria. 3) Ex: Pelomyxa, Mastigamoeba, and Mastigella.

Phylum Heterokonta

1) Motile life cycle stage in which the flagellate cells possess two differently shaped flagella. *Over 100,000 described species, most of which are algae.

Phylum Heterokonta Class Opalinea

1) Numbers of this group are unusual, bearing a superficial likeness to ciliates. 2) About 150 species of this group have been described, virtually all being commensals in the lower intestines of anurans (frogs) and a few in fish, salamanders, and aquatic-base reptiles. 3) They are relatively large with oblique rows of cilia-like flagella which covers the entire body. 4) Have two to many nuclei or similar structure, have no cytostomes, and are known to reproduce sexually by anisogamous singly and therefore are no longer placed with ciliates. 5) Represented by Opalina and Zelleriella

The Flagellated Characteristics

1) One or more flagella present in the trophozoite stage. Some species may have pseudopodia in limited aspects of their life cycles. 2) Some species may occur individually (solitary) or in some cases certain species may form colonies (colonial) 3) The mode of reproduction is generally asexual by symmetrogenic binary fission. Sexual reproduction has not been documented in most cases. 4) Commonly this subphylum has been divided into two groups: Phytoflagellates & Zooflagellates.

Spiral Cleavage Phyla

1) Platyhelminthes: planaria, tapeworms, flukes 2) Nemertina or Rhynchocoela: proboscis worms 3) Acanthocephala: spiny-head worms 4) Entroprocta: bryozoan-like invertebrates 5) Annelida: earthworms 6) Mollusca: snails, clams, squids

Phylum Amoebozoa

1) Polyphyletic grouping that contains cells with pseudopodia that lack microtubules. Microtubules are only associated with the mitotic spindle. no flagella or centrioles. 2) There are two groups: The Lobosea and Filosea *both contain testate (shelled) and atestate (naked) species.

Phylum Choanoflagellata

1) Presence of a single flagellum surrounded by a cylindrical collar. 2) Marine & freshwater species. 3) Some species are sessile and may have a lorica (a girdle-like "skeleton" as seen in rotifers). 4) These are both solitary and colonial forms and members of this order are believed to be more closely related to metaozan animals than the other protozoan groups. 5) Codgosiga, Proterospongia, and Salpingoeca are representative genera.

Phylum Apicomplexa Class Hematozoa

1) Schizogonic phase in RBC's of host. 2) Always uses an arthropod vector host. 3) Major genera are Plasmodium (P. falciparum, P. vivax, P. malariae, and P. ovale). 4) Leucocytozoan and Haematoproteus

Phylum Porifera (Sponges)

1) Sessile, aquatic animals which live primarily in marine systems. 2) Generally they are thought to be relatively primitive animals because they do not have true tissues or organs, however, some minimal cellular differentiation is present. 3) The body is composed of a series of water canals whose organization depends on the types of sponge. 4) The body is supported by a "skeleton" composed of organic spongin fibers or siliceous or calcareous spicules. 5) Generally, waste removal, exchanges of gases and intake of food is dependent on the current set up by the choanocytes to move water through the body wall via ostia then into the inner chamber (the spongocoel) and out the top through the osculum. 6) These organisms are hermaphroditic and in most, a blastula larva forms from the zygote. 7) There are three morphological types: Asconoid, Syconoid, & Leuconoid.

The number of times a lake will turn over depends largely on what?

1) Temperatures experienced throughout the year in the region. 2) The depth of the lake. 3) the physical and geological features of the lake.

Phylum Haptophyta

1) The cells have two unequal flagella and the unique haptonema organelle, which resembles a flagellum but is not used for locomotion. 2) These include important species for aquaculture industries. 3) Ex: All coccolithophores, Isochrysis, and Prymnesium

Phylum Actinopoda Class Heliozoa

1) The heliozoans are a group composed primarily of freshwater species some of which are planktonic and some of which are benthic. 2) Generally they tend to be spherical with fine needle-like pseudopodia called axopodia, which radiate in all directions from the body giving the appearance of a sun-like symbol. 3) Each axopod contains a central axial supporting rod which is covered with granular, adhesive cytoplasm. 4) The rod is ocmposed of a bundle of microtubules. 5) The body of these organisms is composed of two parts, an outer ectoplasmic sphere called the cortex and the inner medulla which is composed of dense endoplasm where the rods are anchored. 6) Some are multi-nucleated. 7) Some are naked, however, many have outer shells which are usually composed of foreign materials including such things as living diatoms. 8) Some secrete siliceous particles which become imbedded in a matrix to form the shell.

Marine Environment

1) The oceans of the world cover approximately 71% of the earth's surface. 2) Salinity on the open ocean is relatively constant, ranging from 34 to 36 parts per thousand. 3) Light & temperature are variable, depending largely on the depth of the water 4) Life forms are not uniformly distributed in the oceans, largely because of the suitability of habitat available where animals and plants can live.

Sporogonic

1) The zygote will divide asexually forming sporozoites which are then infective when the vector host takes a second blood meal. In these where there is no vector a sporulated oocyst may be formed. 2) These then initiate the Schizogonic Phase.

Phylum Axostylata Order Hypermastigida

1) These are multi-flagellated protozoa with kinetosomes arranged in a circle, plate, or longitudinal or spiral rows. 2) Many species are of special interest because they are mutualists found in the intestines of wood-roaches and termites. 3) The best known genus is Trichonympha.

Phylum Ciliophora Class Spirotrichea

1) These ciliates with oral membranelles that wind clockwise to the cytostome, typically with cylindrical or dorsoventrally flattened bodies. 2) In this group the oral region has conspicuous buccal membranes in the adoral zone. 3) Body ciliation is uniform in some species and many have compound ciliary structures (cirri). 4) This class is represented by four subclasses.

Phylum Axostylata Order Trichomonadida

1) These generally have an oval body with four to six flagella 2) Most have four flagella, but all have one of the flagella trailing and often this trailing flagellum will have an undulating membrane. 3) These generally have an axostyle present and a cytostome present anteriorly. 4) These are directly-transmitted parasites, usually found in the alimentary canal, however, one species of the genus Trichomonas, T. vaginalis is found in the human vagina and the male urogenital tract and is a sexually transmitted disease. 5) No cysts have been demonstrated for these parasites.

Phylum Cryptophyta *Also known as the cryptomonads

1) These small algae cells have plastids and are typically flattened in shape, with an anterior groove or pocket where two unequal flagella reside. 2) Distinguished from other groups by their extrusomes. 3) Ex: Chilomonas, Rhodomonas, and Goniomonas

Phylum Foraminifera

1) They have delicate granular reticulopodia (consisting of a network of filopodia). 2) Most species are marine and have multi-chambered "shells" (multilocular) 3) A few have single chambered "shells" (unilocular). 4) Most are benthic dwellers, but a few, like Globigerina, are planktonic. 5) Members of the genus Homotrema are sessile associated with some coral communities.

Phylum Ciliophora Class Nassophorea

1) This class is characterized by transverse microtubule ribbons that run tangential to the basal bodies. 2) Only one order is recognized: Order Peniculida 3) These have an oral apparatus that is an elastic slit and three oral membranelles on its left side and may have an undulating membrane on the right (Ex: Paramecium).

Phylum Actinopoda Class Acantharea

1) This class superficially resembles the radiolaria, but have radiating skeletons composted of strontium sulfate. 2) These are marine and the primary genus is Acanthometra.

Phylum Heterokonta Class Bacillariophycea

1) This is a very diverse group where individuals may frequently be confined in a coating or shell that is composed of two valves, a large top valve, and a smaller bottom valves that fits into the upper valve somewhat like a Petri dish. 2) This outer cover is composed of pectin impregnated with silicon giving it a glass-like quality. 3) Some species are flagellated, a few are amoeboid, and others may form filamentous colonies. 4) Probably the best known members of this group are the diatoms. 5) Diatoms may be radially, biradially, triradially symmetrical.

Phylum Ciliophora

1) This is apparently a very homogeneous group which has over 8,000 species described in it. 2) All have cilia or compound ciliary structures (cirri) for locomotion at least in some aspect of their life history. 3) They also have an infracilliature composed of ciliary basal bodies or kinteosomes which are found just under the cell surface and are associated with the cilia. 4) The infracilliature is present even in stages that do not have cilia. 5) Most species have a cytostome or cell mouth and all have two types of nuclei present: A. One macronucleus: vegetative, concerned with synthesis of RNA and DNA. B. One micronucleus: reproductive, concerned only with synthesis of DNA. 6) Reproduction is frequently by transverse fission and sexual reproduction never includes the production of free gametes. 7) Many are solitary and free-swimming, however, both sessile and colonial forms occur. 8) Some have an outer covering called a lorica which is composed of either secreted material of foreign material cemented together. 9) *CONTINUE READING ON SLIDES

Invasion of Terrestrial Environments

1) Those lineages which invade the terrestrial environment encountered a number of problems which required peculiar adaptations. 2) The air surrounding these organisms provided no buoyancy and therefore balancing, locomotion, and support of the mass of the organisms body became limiting factors (Ex: Fins were of little use to organisms invading land, but legs and other more functional modes of movement were an advantage) 3) Also, exoskeletons or internal skeletal were required to support body mass, but also to withstand the torque created by locomotory appendages, which could no longer depend on buoyancy to alleviate stress.

Testate Amoeboids

1) Those with outer coverings or shells are primarily fresh water species. Sometimes considered a phylum. 2) The shells of some amoebas are secreted by the cytoplasm and are composed of chitinoid or siliceous materials , however, some species imbed foreign material in a cement-like matrix which is attache dot the amoeba with protoplasmic strands. 3) In the latter type of covering there is usually a large opening through which the pseudopodia can be protruded.

Phylum Apicomplexa Class Coccidia

1) Trophozoites are generally small intercellular bodies. 2) Schizogony present, asexual and sexual phases in life cycles. 3) Usually in epithelium and blood cells of invertebrates and vertebrates. 4) Ex: Crytosporidium, Eimeria, Haemogrearina, and Toxoplasma

Phylum Heterokonta Class Opalinea Order Opalinida Family Opalinida

1) Two to many nuclei are present 2) Generally commensalistic in the lower digestive tract of amphibians 3) Main genus is Opalina

Phylum Euglenozoa Class Euglenoidea

1) Unicellular 2) Flagellated 3) Asexual reproducing organisms which in most species are also photosynthetic 4) Generally flask-shaped and lack a rigid cell wall 5) Two flagella, one long flagellum arising from an anterior gullet and a second small flagella in the gullet. *The gullet (cytostome) is a mouth-like structure which is used in most members of the group to take in food particles or smaller algae. *These are primarily freshwater species and are represented by the genera: Euglena, Phacus, Pernamena, Rhabdomonas.

General Characteristics of Protists

1) Unicellular 2) May be autotrophic, holographic, saprotrophic, or mixotrohpic 3) Reproduction may be both asexual and sexual 4) Locomotion may be cilia, flagella, pseudopodia, or they may be sessile 5) Animal-like (Protozoa) vs. Plant-like (Protophyta) 6) All have a nucleus or nucleus-like structures present. Two types of nuclei can be found: vesicular or compact

Biogeographic Regions (Based on Plants)

1. Boreal 2. Paleotropical (African, Indo-Malaysian, and Polynesian) 3. Neotropical 4. South African 5. Australian 6. Antarctic

The Zoogeographic Regions

1. Palearctic 2. Ethiopian 3. Oriental 4. Australian 5. Neoarctic 6. Neotropical *The Palearctic & Neoarctic are often included in the same region, the Hoalrctic.

Biomes

1. Tundra 2. Northern Conifer Forest 3. Temperate Deciduous & Rain Forest 4. Temperate Grassland 5. Chaparral 6. Desert 7. Tropical Rain Forest 8. Tropical Deciduous Forest 9. Tropical Scrub Forest 10. Tropical Grassland & Savanna 11. Mountains

The pH of seas generally remain between _____ and ______.

8.0 and 8.4

Mixotrophic

A combination of autotrophic, holotrophic, and saprotrophic.

Thermocline/Mesolimnion/Metalimnion

A density gradient (pyncnocline) between upper epilimnion and lower hypolimnion. This region is essentially a graduation of temperatures going from warmer at the interface with the epilimnion to colder at the interface with hypolimnion.

Cytopyge

A fixed location on surface of certain protozoans from which wastes are discharged by exocytosis.

Choanocyte

A flagellated collar cell found in sponges.

Contractile Vacuole

A fluid-filled membrane-bound body in the cytoplasm of protozoans responsible for osmoregulation and to some extent waste removal.

Mesoglea (mesohyl)

A gelatinous material and it's associated elements in the body wall of sponges and between the epidermal layer and the gastroderm in radiate animals.

Phylogenetic Tree

A graphical representation of the ancestry of groups. * Representation of the interrelationships and assumed evolutionary history of a group of organisms which strives to indicate the relative order of successive divisions in the line of decent, coincident with past speciation events.

Phylum

A major taxonomic grouping or unit of related, similar classes of animals.

Spongin

A meshwork of protein fibers in the "skeleton" of advanced sponges.

Endosome

A nucelolus-like structure found within the vascular type of nucleus of protozoans that does not disappear during mitosis.

Chloroplasts

A plastid containing chlorophyll.

Myoneme

A protein-lipid fiber in the cell membrane and cell involving contractibility.