Chapter 12 Flashcards
A typical eukaryotic nucleus may be
Haploid / diploid
It divides by mitosis in four phases __ resulting in two nuclei with the same ploidy as the original.
prophase, metaphase, anaphase, and telophase
nuclear division that results in four nuclei, each with half the ploidy of the original.
Meiosis
A cell’s cytoplasm divides by
Cytokinesis
are multinucleate cells resulting from repeated mito- ses but postponed or no cytokinesis.
Coenocytes
Some microbes undergo multiple mitoses by schizogony to form a multinucleate
Schizont
are eukaryotic, unicellular
organisms that lack cell walls.
Protozoa
the feeding stage of a typical protozoan
Motile trophozoite
Most protozoa are ___ getting their energy from chemicals and their carbon from other organisms, but dinoflagel- lates and euglenoids are photoautotrophs.
Chemo heterotrophs
A few protozoa undergo sexual reproduction by forming
Gametocytes
Gametocytes fuse to form a
Zygote Te
Protozoa may be classified into six groups
parabasalids, diplo- monads, euglenozoa, alveolates, rhizaria, and amoebozoa.
are characterized by a Golgi body–like structure called a parabasal body
Parabasalids
are euglenozoa that store food as paramylon, lack cell walls, and have eyespots used in positive phototaxis.
unicellular flagellated euglenids
euglenozoan with a single, large, apical mito- chondrion that contains a kinetoplast, which is a region of DNA.
Kinetoplastid
Alveolates, with cavities called alveoli beneath their cell surfaces, include
ciliate
apicomplexans
dinoflagellas
Protozoa that move and feed with pseudopods are
amoebas
2 kingdoms of amoebas
rhizaria
amoebazoa
which have threadlike pseudo- pods and calcium carbonate shells
Foraminifera
which have threadlike pseudopods and silica shells.
Radiolaria
despite their name, are not fungi but are a kind of amoeba.
Slime molds
kinds of slime molds
plasmodial
cellular
are chemoheterotrophic eukary-
otes with cell walls usually composed of chitin.
Fungi
Most fungi are beneficial, but some produce
Mycoses
Mold bodies are composed of tubular filaments called h
Hyphae
Hyphae are described as either
Septate / aseptate
is a tangled mass of hyphae.
Mycelium
either moldlike (with hyphae) or yeastlike, depending on environmental conditions.
Dimorphic fungus
they acquire nutrients by absorption from dead organisms.
Saprobes
Other fungi get nutrients from living organisms using that penetrate host tissues.
haustoria
Most fungi in the division Zygomycota produce
rough-walled
zygosporangia
intra-
cellular parasites formerly classified as protozoa but now classed with zygomycetes based on genetic analysis.
Microsporidia
a group of economically
important fungi, produce ascospores within sacs called asci.
Ascomycota
have fruiting bodies called basidiocarps that include mushrooms, puffballs, and bracket fungi. Basidiocarps produce basidiospores at the ends of basidia.
Basidiocarps
economically and environmentally important organ- isms composed of fungi living in partnership with photosynthetic microbes, either green algae or cyanobacteria.
Lichen
imperfect (fungi) are an informal grouping of fungi having no known sexual stage.
deuteronycetes
are photosynthetic organisms in which every cell of the
reproductive structures becomes a gamete.
algae
The study of algae is , and the scientists who study them are phycologists.
phycology
Algae typically reproduce by an in which a haploid body alternates with a diploid bod
alternation of generations
contains green algae, which are metaboli- cally similar to land plants.
chlorophyta
red algae, contain the pigment phycoerythrin, the storage molecule glycogen, and cell walls of agar or carrageenan, substances used as thickening agents
rhodophyta
brown algae, contain xanthophylls, laminarin, and oils. They have cell walls composed of cellulose and alginic acid, which is another thickening agent. A brown algal spore is motile by means of one “hairy” flagellum and one whiplike flagellum.
phaotophyta
the golden algae, yellow-green algae, and diatoms—contain chrysolaminarin as a storage product. The silica cell walls of diatoms are arranged in nesting halves called frustules.
chrysophyta
have tubular cristae in their mitochondria, cell walls of cellulose, spores having two different flagella, and diploid bodies. They are placed in the kingdom Stramenopila along with chrysophytes and brown algae.
water molds
animals that carry and transmit pathogens.
athropod vectors
