Chapter 12: The Eukaryotes: Fungi, Algae, Protozoa, and Helminths

Schizogony

Schizogony

________ is multiple fission; the nucleus undergoes multiple divisions before the cell divides.

T vaginalis

Like some other flagellates, ________ has an undulating membrane, which consists of a membrane bordered by a flagellum.

chlamydoconidium

A(n) ________ is a thick- walled spore formed by rounding and enlargement within a hyphal segment.

lichen

A(n) ________ is a combination of a green alga (or a cyanobacterium) and a fungus.

diploid zygote

The (+) and-) (nuclei fuse to form a(n) ________ nucleus.

Arthropods

________ that carry pathogenic microorganisms are called vectors.

Yeasts

________ are nonfilamentous, unicellular fungi that are typically spherical or oval.

amebae move

The ________ by extending blunt, lobelike projections of the cytoplasm called pseudopods.

lichens thallus

The ________, or body, forms when fungal hyphae grow around algal cells to become the medulla.

Dinoflagellates

________ are unicellular algae collectively called plankton, or free- floating organisms.

protozoa

Some ________ produce gametes (gametocytes), which are haploid sex cells.

Eugle

________- noids have a semirigid plasma membrane called a pellicle, and they move by means of a flagellum at the anterior end.

Thalli

________ of the larger multicellular algae, those commonly called seaweeds, consist of branched holdfasts (which anchor the alga to a rock), stem- like and often hollow stipes, and leaflike blades.

small particulate

The feeding and growing stage, or trophozoite, feeds upon bacteria and ________ nutrients.

Euglenoids

________ are photoautotrophs.

zygospore

A(n) ________ is a large spore enclosed in a thick wall.

tachyzoites

The trophozoites, called ________, reproduce sexually and asexually in an infected cat, and oocysts, each containing eight sporozoites, are excreted with feces.

diploid nucleus

The ________ gives rise to haploid nuclei (sexual spores), some of which may be genetic recombinants.

Adult helminths

________ may also be monoecious, or hermaphroditic- one animal has both male and female reproductive organs.

Conidia

________ formed by the fragmentation of a septate hypha into single, slightly thick- ened cells are called arthroconidia.

Males

________ are smaller than females and have one or two hardened spicules on their posterior ends.

Seasonal changes

________ in nutrients, light, and temperature cause fluctuations in algal populations; periodic increases in numbers of planktonic algae are called algal blooms.

ciguatera

A disease called ________ occurs when the dinoflagellate Gambierdiscus toxicus (GAM- be ̄- er- dis- kus TOKS- i- kus) passes up the food chain and is concentrated in large fish.

Fungus

________ are important in the food chain because they decompose dead plant matter, thereby recycling vital elements.

Fungal hyphae

________ also form a cortex, or protective covering, over the algal layer and sometimes under it as well.

Paramecium

The ciliates, such as ________, reproduce sexually by conjugation, which is very different from the bacterial process of the same name.

Spicules

________ are used to guide sperm to the females genital pore.

blood parasites

The hemoflagellates (________) are transmitted by the bites of blood- feeding insects and are found in the circulatory system of the bitten host.

plasmodial slime mold

A(n) ________ exists as a mass of protoplasm with many nuclei (it is multinucleated)

Any fungal infection

________ is called a mycosis.

Fission yeasts

________, such as Schizosaccharomyces, divide evenly to produce two new cells.

Slime molds

________ are closely related to amebae and are placed in the phylum Amoebozoa.

Helminths

________ are multicellular eukaryotic animals that gener- ally possess digestive, circulatory, nervous, excretory, and reproductive systems.

Fungi

________ that infect only the epidermis, hair, and nails are called dermatophytes, and their infections are called dermatomycoses or cutaneous mycoses.

Fungal hyphae project

________ below the lichen body to form rhizines, or holdfasts.

fungal sexual spore results

A(n) ________ from sexual repro- duction, which consists of three phases:

Subcutaneous mycoses

________ are fungal infections beneath the skin caused by saprophytic fungi that live in soil and on vegetation.

Dinoflagellates

________ in the genus Alexandrium produce neurotoxins (called saxitoxins) that cause paralytic shellfish poisoning (PSP)

Arthropods

________ are animals characterized by segmented bodies, hard external skeletons, and jointed legs.

Conidia

________ are produced in a chain at the end of a conidiophore.

Adult helminths

________ may be dioecious; male reproductive organs are in one individual, and female reproductive organs are in another.

Plasmodial slime molds

________ were first scientifically reported in 1729.

plasmodial slime molds

When ________ are grown in laboratories, a phenomenon called cytoplasmic streaming is observed, during which the protoplasm within the plasmodium moves and changes both its speed and direction so that the oxygen and nutrients are evenly distributed.