zoology

Haploid cells that are unequal in size, such as sperm and egg, are called isogametes. unigametes. autogametes. anisogametes. syngametes.

anisogametes

Cells that move about in the mesohyl, digest particles, and may specialize for other functions are the lophocytes. spongocytes. choanocytes. archaeocytes.

archaeocytes

The simplest of canal systems is found in the syconoids. leuconoids. asconoids.

asconoids

Most of the time, although they usually have other options, protozoans reproduce by parthenogenesis. asexual cell division. autogamy. fusion of gametes. conjugation.

asexual cell division.

The strange case of organisms that undergo meiosis to produce gametes that fuse to form a zygote internally without leaving the organism is a process called zygotic meiosis. syngamy. gametic meiosis. autogamy. conjugation.

autogamy

What are long, thin pseudopodia supported by axial rods of microtubules called? lobopodia filopodia reticulopodia axopodia actinopodia

axopodia

Which is a member of the apicomplexan group of protists? Chlamydomonas Paramecium Plasmodium vivax Trypanosoma Amoeba proteus

Plasmodium vivax

Chalky fossils that formed the White Cliffs of Dover were produced by diatoms (as diatomaceous earth). radiolarians. foraminiferans. dinoflagellates. ciliates.

foraminiferans

How does the mosquito transmit malaria from an ill person to a healthy person? -Plasmodium is taken up from one person's blood and squirted back out into the next person. -Plasmodium gametocytes are taken up from one person's blood, fuse to form a zygote that becomes a motile ookinete that enters the saliva ducts. -Plasmodium gametocytes are taken up from one person's blood and cross into the saliva duct to be reinjected into the next person. -Plasmodium gametocytes are taken up from one person's blood, fuse to form a zygote that becomes a motile ookinete, that crosses the stomach wall, forms an oocyst that undergoes sporogony and the sporozoites then migrate to the saliva ducts to be injected into the human host.

-Plasmodium gametocytes are taken up from one person's blood, fuse to form a zygote that becomes a motile ookinete, that crosses the stomach wall, forms an oocyst that undergoes sporogony and the sporozoites then migrate to the saliva ducts to be injected into the human host.

What are the functions of the macronucleus and one or more small micronuclei in Paramecium? -A micronucleus is always (1n) for conjugative reproduction, the macronucleus functions for general cell coding, and the two are otherwise unrelated. -The macronucleus undergoes meiosis to produce haploid micronuclei that are exchanged in conjugation; this then produces a micronucleus for general cell housekeeping. -The micronucleus undergoes meiosis to produce haploid micronuclei that are exchanged in conjugation; the macronucleus is responsible for the "day-to-day" functions of the cell. -Diploid micronuclei control the cell and the haploid macronuclei are exchanged in conjugation for reproduction. -None of the choices is correct.

-The micronucleus undergoes meiosis to produce haploid micronuclei that are exchanged in conjugation; the macronucleus is responsible for the "day-to-day" functions of the cell.

A Paramecium "knows" when it has encountered a noxious substance and backs off to veer away. As a one-celled organism, how does it "know" to do this? -The macronucleus has DNA coding that determines this reaction. -This cell is essentially a small neuron, or nerve cell. -This is a rather simple stimulus that changes the electrical potential difference across the cell membrane and depolarization of the membrane results in cilia reversing their direction of beating. -The micronucleus is dedicated to controlling just such responses. -None of the choices is correct.

-This is a rather simple stimulus that changes the electrical potential difference across the cell membrane and depolarization of the membrane results in cilia reversing their direction of beating.

Protozoans in the genus Trypanosoma cause birth defects if infecting a woman at the appropriate stage of pregnancy. African sleeping sickness and Chagas disease. malaria in both humans and birds. Toxoplasmosis, often contracted from cats. amebic dysentery and intestinal ailments.

African sleeping sickness and Chagas disease.

Which of the following is NOT a "ciliate?" Stentor Vorticella Paramecium Trichodina All of the choices are classified as ciliates.

All of the choices are classified as ciliates.

Reproduction in at least some sponges is sexual with both male and female sex cells in one individual. asexual by gemmules. asexual by budding. asexual by fragmentation. All of the choices are correct

All of the choices are correct

Which unicellular eukaryote is NOT correctly linked to the type of movement structure it possesses? Amoeboids-pseudopodia Paramecium-flexibility of the pellicle Dinoflagellates-flagella Ciliates-cilia Apicomplexa-reticulopodia

Apicomplexa-reticulopodia

Which protozoan group has a complicated parasitic life cycle that nearly always involves the production of infective spores? Zooflagellates Sarcodines Rhizopods Ciliates Apicomplexans

Apicomplexans

Which describes the mode of action of the causative agent of amebic dysentery? -It invades the liver and destroys its function, thus altering the digestive system. -It invades the brain and destroys the control center that regulates intestinal movement of food. -It invades the intestinal lining and secretes enzymes that cause loss of fluid; it can also cause abscesses on the liver and other organs. -It ruptures large numbers of red blood cells and the increased fluids are lost across the intestine. -All of the choices are correct.

It invades the intestinal lining and secretes enzymes that cause loss of fluid; it can also cause abscesses on the liver and other organs.

Which of the following is/are correct descriptions of unicellular eukaryote characteristics? When found in other organisms, they are typically parasitic or pathogenic. They all lack symmetry. No germ layers are ever formed. They are all aquatic. As primitive organisms, they are restricted to asexual reproduction.

No germ layers are ever formed.

Which is an example of a Ciliophoran protozoa? Trypanosoma Plasmodium Amoeba Giardia Paramecium

Paramecium

To what extent are the cells of a colonial Volvox specialized? Germ cells specialize in locomotion, others in nutrition, and others in reproduction. The cells of Volvox are not specialized at all; all are equivalent in function and to be otherwise would make them like those of the metazoa. A Volvox cell alternates between first being somatic, then being reproductive. Somatic cells function in nutrition and locomotion while a few "germ" cells carry out reproduction. Volvox is like two organisms living together symbiotically: one set of cells handles nutrition and locomotion and reproduce their type; another type of cell handles sexual reproduction and reproduce their type.

Somatic cells function in nutrition and locomotion while a few "germ" cells carry out reproduction.

Flagellated canals of syconoid sponges form by evagination of the body wall and these sponges often develop through a simple vase-like stage. Which of the following is a logical hypothesis based on this evidence? Syconoid sponges were derived from asconoid ancestors. Leuconoid sponges were derived from asconoid ancestors. Asconoid sponges were derived from syconoid ancestors. Syconoid sponges were derived from leuconoid ancestors. Leuconoid sponges were derived from syconoid ancestors.

Syconoid sponges were derived from asconoid ancestors.

Some organisms undergo meiosis to produce gametes that fuse to form a zygote internally without leaving the organism. What is the effect of this process on genetic diversity of the offspring? The offspring could vary from the parent but there would be less genetic variation because this is inbreeding. The offspring would be identical clones of the parent. The offspring would vary from the parent because it would produce different recombinations of each chromosome pair. The offspring would become more and more genetically diverse each generation. None of the choices is correct.

The offspring would vary from the parent because it would produce different recombinations of each chromosome pair.

Which statement about adult sponges is false? They do not have a mouth. Their apparently simple structure is deceptive. Their bodies are usually asymmetrical. Their bodies are aggregations of one cell type.

Their bodies are aggregations of one cell type.

Which is NOT a trait of sponges? Amoeboid cells digest food and make skeletal fibers and gametes Water enters through the osculum Their body wall has two incipient "cell layers" Their flagellated collar cells move water They are sessile filter feeders

Water enters through the osculum

The most likely mechanism for removing excess water by contractile vacuoles is simple osmosis of water across the cell membrane. a proton pump that also pulls water into the vacuole. differential fluid pressure. an ampulla that forms suction. reverse osmosis.

a proton pump that also pulls water into the vacuole.

The early development of a globular colony (with flagella inward) that then turns inside-out (with flagella outward) is called inversion, and it is very common in early development in many animal groups. called an undulating membrane and is common among ciliates. called reverse gastrulation and it is very rare among animals. a pseudoplasmodium and only found in protozoans. called inversion, and it is very rare among animals, only occurring in colonial flagellates and sponges.

called inversion, and it is very rare among animals, only occurring in colonial flagellates and sponges.

Cells responsible for water flow and capture of some particles are the lophocytes. pinacocytes. choanocytes. archaeocytes. myocytes.

choanocytes

Which protozoan is used to test hypotheses of how multicellular organisms arose from their closest unicellular relatives? microsporidians opalinids choanoflagellates kinetoplastans retortamonads

choanoflagellates

The structural protein found in all sponges is collagen. elastin. gorgonin. spiculin. None of the choices is correct

collagen

What is the specific structure in ciliates that serves as the site of expulsion for wastes called? phagosome cytoproct paramylon body lysosome cytostome

cytoproct

"Red tides" are caused by massive blooms of dinoflagellates. Euglena. sporozoans. ciliates. Plasmodia.

dinoflagellates

Giardia lamblia causes malaria in both humans and birds; is carried by mosquitoes. Toxoplasmosis; contracted from cats. dysentery and intestinal ailments; is found in contaminated water. African sleeping sickness; is carried by the tsetse fly. birth defects; is caused by mosquitos.

dysentery and intestinal ailments; is found in contaminated water.

A protozoan with both plant-like photosynthesis and animal-like motility is most likely a dinoflagellate. sporozoan. euglenoid. ciliate. zooflagellate.

euglenoid

The great pyramids of Egypt are made from stone formed from fossil radiolarians. endoparasitic amoeboids of insects. heliozoans. snails. foraminiferans.

foraminiferans.

The protozoan dictyosome is called what in other eukaryotes? mitochondrium ribosome plastid endoplasmic reticulum golgi apparatus

golgi apparatus

The most correct usage of the term "protozoa" is as a(n) phylum. class. synonym for Protista. separate kingdom. informal cluster of groups with complicated and uncertain phyletic relationships.

informal cluster of groups with complicated and uncertain phyletic relationships.

The distinction between phagotrophs (or holozoic feeders) and osmotrophs (or saprozoic feeders) is a difference between ingesting visible particles or organisms versus ingesting dissolved substances, sometimes from dead organisms. diffusion of food across the membrane versus engulfing food in a vacuole. producing your own food versus using the chemical bonds in food molecules made by others. eating living and eating dead organic material. direct transport versus indirect transport of food molecules.

ingesting visible particles or organisms versus ingesting dissolved substances, sometimes from dead organisms.

Specialized archaeocytes that secrete large quantities of collagen are choanocytes. spongocytes. collencytes. lophocytes.

lophocytes

The largest impact that the loss of sponges would have on the environment would be alteration of ocean currents. loss of filtration. extinctions of other species that are symbionts of sponges. collapse of most food chains. alteration of gases in water and the atmosphere.

loss of filtration.

The extracellular matrix found in sponges is pinacoderm. spongin. collagen. mesohyl or mesenchyme.

mesohyl or mesenchyme.

Mosquitoes that transmit malaria pick up what stage(s) when feeding on the blood of a patient ill with malaria? microgametocytes and macrogametocytes that mature into gametes in the insect host trophozoites in red blood cells sporozoites from the oocysts merozoites that escape from the red blood cells hemozoin stored in red blood cells

microgametocytes and macrogametocytes that mature into gametes in the insect host

The modified cells of sponges that form circular bands and provide just a little constriction to control water flow are choanocytes. amoebocytes. myocytes.

myocytes

Concerning producing larger organisms without cellular differentiation, nature has never evolved larger organisms because it would never work. the more derived the organism, the more differentiated and the smaller the cell size. this has never occurred since the ancestral cell was small. nature has evolved larger unicellular organisms but they are rare and have surface-to-volume limitations.

nature has evolved larger unicellular organisms but they are rare and have surface-to-volume limitations.

Which of the following represents the arrangement of microtubules in axonemes of cilia? nine peripheral pairs of microtubules plus one central pair three peripheral pairs of microtubules and no central pairs nine peripheral triplets of microtubules nine peripheral triplets of microtubules plus one central pair nine peripheral pairs of microtubules plus two central pairs

nine peripheral pairs of microtubules plus one central pair

The order in which a drop of ink would pass by the structures in an ascon sponge is osculum-spongocoel-ostia. ostia-osculum-spongocoel. ostia-spongocoel-osculum. spongocoel-ostia-osculum. osculum-ostia-spongocoel.

ostia-spongocoel-osculum.

Members of Euglena have starch-like food storage material in the form of kinetosomes. flagellar bodies. chloroplasts. stigmata. paramylon bodies.

paramylon bodies.

In most sponges, the free-swimming larva produced by sexual reproduction is called a(n) apopyle. parenchymula. plasmodium. gemmule. bud.

parenchymula

The outer thin, flat, epithelial-like cells that cover the outside and some inside surfaces of sponges, are amoebocytes. choanocytes. spongin. spicules. pinacocytes.

pinacocytes.

Most ciliophoran protozoa possess a cytostome. are marine. possess flagella. are parasitic. have cyst stages for surviving harsh conditions.

possess a cytostome.

If a sponge is fragmented and cells are dissociated from one another, the cells will reorganize their structure and function, and clumps of isolated cells will form a new sponge. form spicules in the pattern of the cloth. die from being separated. reproduce sexually.

reorganize their structure and function, and clumps of isolated cells will form a new sponge.

Specialized archaeocytes that secrete spicules are sclerocytes. lophocytes. collencytes. spongocytes. choanocytes.

sclerocytes

Calcareous or siliceous elements of the sponge body wall provide support. These elements are called choanocytes. amoebocytes. spicules. pinacocytes. spongin.

spicules

Specialized archaeocytes that secrete spongin are lophocytes. choanocytes. spongocytes.

spongocytes

Usually we expect fission to produce two cells from one, but in Sporozoea and some Sarcodina, multiple fission of the nucleus is followed by rapid division of cytoplasm, releasing many new individuals immediately in a process called syngamy. budding. sporogony. amitosis. autogamy.

sporogony

The sponges date back to the early time of anaerobic prokaryotes. the Devonian period or "age of fishes." the Cambrian period and probably earlier. the time of the first prokaryotes but the sponges left no fossil evidence for lack of hard parts.

the Cambrian period and probably earlier.

In glass sponges, archaeocytes fuse their pseudopodia to form a trabecular reticulum. spongin network. leuconoid framework. bud. micropyle.

trabecular reticulum.

The unique feature of sponge development in members of the class Calcarea is the amphiblastula which generates gemmules. controls the process of regeneration. determines the types of spicules produced. turns inside out during its development.

turns inside out during its development.

When a nucleus has chromatin that is clumped, leaving clear areas within the nucleus, the appearance is described as spicular. micronuclear. pellicular. kinetosomic. vesicular.

vesicular

What is the function of the contractile vacuole in protozoa? digestion excretion of nitrogen wastes respiration locomotion water balance

water balance

The strange case of organisms that undergo meiosis after fertilization and live out their adult life in the haploid state is a case of autogamy. conjugation. syngamy. gametic meiosis. zygotic meiosis.

zygotic meiosis.