Study Questions CH 10, CH 11

Who is responsible for the hierarchical system of classification?

Linnaeus

What type of locomotive structures are used by Centrohelidae? What is their habitat and nutrition strategy?

Locomotive - axopodia Habitat - freshwater and marine Nutrition - predators testate (silica amoebas)

Characterize the Ameobozoa with respect to locomotive structures, habitat, and nutritional strategy. List some examples within this clade including free-living and parasitic amebas.

Locomotive - flagella, psuedopodia, lobopodia Habitat - freshwater and marine Nutritional strategy - predators and parasites Examples - a. Slime molds (moist terrestrial with pseudopodia) b. Free living - amoeba proteus, arcella (naked and testate with lobopodia) c. Entamoebas (parasitic) Entamoeba histolytica - causes amebic dysentery

Describe how different criteria are used in species identification.

a. Common Descent - trace ancestry to common ancestral populations b. Smallest distinct groupings - organisms sharing patterns of ancestry descent c. Reproductive community - excluded from reproducing with other populations in nature d. Geographic range - distribution across space i. Cosmopolitan - worldwide range ii. Endemic - restricted range e. Evolutionary duration - distribution across time

List and describe the features of a phylogenetic tree.

a. Common ancestor - ancestor to two or more lines of descent b. Ancestral trait - trait that is found in common ancestor c. Lineage - branch of descendant of common ancestor d. Derived trait - trait that is not found in common ancestor

Vesicle

Small membrane-bound sac that functions in moving products into, out of, and within a cell.

How do monophyletic, paraphyletic, and polyphyletic taxa differ?

a. Monophyletic taxon - contains all the descendants of a particular ancestor (clade) b. Polyphyletic taxon - contains some members that don't share a common ancestor c. Paraphyletic taxon - contains some, but not all, descendants of a particular ancestor

What types of character traits are used to construct phylogenetic trees?

a. Morphological traits (anatomy) b. Molecular traits (DNA, proteins) c. Behavioral traits (parental care) d. Ecological traits (geographical range)

Toxicysts

Structures possessed by predatory ciliate protozoa, which on stimulation expel a poison to subdue the prey

What type of protective coating do amoebas have?

Test - shell of secreted silicon or chitin some are naked without shells

syngamy

The fusion of two gametes in fertilization.

Microtubles

a microscopic tubular structure present in numbers in the cytoplasm of cells, sometimes aggregating to form more complex structures. made of tubulin proteins

List the major characteristics of unicellular eukaryotes.

a. All cells reproduce b. Mostly microscopic - 10-100 um c. All symmetries, shape is variable d. No tissues or organs - would need more cells

Name and describe the current three kingdoms of life.

a. Animalia multicellular animals b. Plantae multicellular plants c. Fungi multicellular fungi

Describe the two theories of eukaryotic cell origin. List supporting evidence for both theories.

a. Autogenous model i. Prokaryotic cell membrane invaginated (folded in on itself) to form nucleus and other organelles b. Endosymbiotic hypothesis i. Eukaryotic cell might have evolved when a prokaryotic ell engulfed another prokaryotic cell c. Evidence: mitochondria have circular DNA & ribosomes, surrounded by a double membrane, independently replicate & are similar in size/structure to prokaryotic cells

List and describe the important features of a cladogram.

a. Plesiomorphy - ancestral character b. Synapomorphy - derived character shared uniquely by all members of clade (not ancestor) c. Outgroup - not part of ingroup (study group), serves as comparison d. Sister taxa - share common ancestry more recently with each other than with other taxa e. Clade - common ancestor and all decedents

Plesiomorphy

ancestral trait

What are the different types of locomotive structures in unicellular eukaryotes?

i. Flagella - propel water parallel to body surface (whip-like), composed of microtubules, long ends ii. Cilia - propel water perpendicular to body surface (oar-like), composed of microtubules, cover whole surface of cell iii. Pseudopodia - actin filaments in lobopodia (blunt); filopodia (thin and pointed); reticulopodia (netlike) 1. Axopodia - thin and pointed with central axoneme containing microtubules

Define taxonomy

identifying and naming organisms and grouping organisms into taxa

Kinetoplast

mass of DNA carried within the single, oversized mitochondrion, characteristic of kinetoplastids (phylum: Euglenozoa)

List and describe the organelles in eukaryotic cells.

nucleus mitochondria Golgi Apparatus lysosome ribosome rough endoplasmic reticulum smooth endoplasmic reticulum vacuole chloroplasts vesicle cytoskeleton

Characterize the features that distinguish the Euglenids. Provide an example of an Euglenid.

1. Autotrophic in light but saprozoic in dark (mixotrophic) 2. Chloroplasts with chlorophyll 3. Contractile vacuole - expels excess water 4. Stigma (red eyespot) - orients towards light 5. Paramylon granules - starch like stored food 6. 2 flagella extend from reservoir at anterior end Example - ??

What is the difference between a direct/simple and indirect/complex life cycle?

1. Direct/simple life cycle = one host 2. Indirect/complex life cycle = 2 or more hosts

What is the difference between a facultative and obligate parasite?

1. Facultative = not normally a parasite but can be parasitic under certain conditions 2. Obligate = true parasite that requires host to complete life cycle

List two categories of heterotrophic feeders.

1. Phagotrophs (holozoic) - feed invisible particles 2. Saprozoic feeders (osmotrophs)—ingest soluble food

What is the difference between ranked and rank-free taxonomic hierarchies? Give an example of each.

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Which taxonomic grouping is preferred by evolutionary taxonomists?

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Describe and give an example of a clade within a cladogram.

A group of organisms believed to have evolved from a common ancestor

Vacuole

A sac inside a cell that acts as a storage area

Axoneme

A structure found in eukaryotic cilia and flagella and responsible for their motion; composed of two central microtubules surrounded by nine doublet microtubules (9 + 2 arrangement).

DNA bar coding

A technique for identifying organisms to the species level using gene sequence information

What are the limitations to the biological species concept?

A) Overlooks variations that occur within species B) Does not take into consideration the changes that happen over time C) Tends to ignore hybridization D) Cannot be used to determine species identity among asexually reproducing organisms or among fossils

Comment on the diversity of unicellular eukaryotes including number of described species, habitat, types and numbers of organelles, and variety of locomotive stuctures.

i. 64,000 described species (1/2) fossils; maybe 250,000 species ii. Aquatic, terrestrial, symbionts iii. Diverse organelles - diverse forms iv. Varying locomotion and food capture - cilia, flagella, pseudopodia (lobopodia, filopodia, reticulopodia)

Contrast heterotrophic, autotrophic, and mixotrophic feeders.

i. Autotrophic - synthesize own food ii. Heterotrophic - obtain food synthesized by other organisms. Mixotrophic - combination of heterotrophy and autotrophy (Ex. Euglena)

Actin filaments

protein fibers that play a role in cell division and shape - made of actin proteins smallest

Tubulin

protein that makes up microtubules

Synapomorphy

shared derived character by all members of a clade

Ribosomes

site of protein synthesis

Golgi apparatus

stack of membranes in the cell that modifies, sorts, and packages proteins from the endoplasmic reticulum

Define phylogeny

the evolutionary history of a group of organisms

Define systematics

the study of biological diversity by establishing evolutionary relationships (phylogeny)

Rough Endoplasmic Reticulum

transport and storage

Flagella

whiplike tails found in one-celled organisms to aid in movement

List and describe the different types of pseudopodia.

Actin filaments in lobopodia (blunt) Filopodia (thin and pointed); Reticulopodia (netlike) 1. Axopodia - thin and pointed with central axoneme containing microtubules

What is the distinguishing feature of all the organisms in the Alveolate clade? List the three Alveolate phyla.

Alveoli - membrane bound sacs underlying plasma membrane Ciliophora, Dinoflagellata, and Apicomplexa

What are the clades included within Rhizaria?

Cercozoa, Foramnifera, and Radiolaria

From what source did the Viridiplantae get their chloroplasts? List some unicellular and colonial members of the Viridiplantae. In what kingdom are these organisms classified?

Chloroplasts from endosymbiosis with cyanobacteria Examples - a. Chlamydomonas - biflagellate cell b. Volvox (large colony w/ division of labor), Gonium (small colony) - colonial form forms when cells are connected by cytoplasmic bridges Kingdom Plantae (Archaeplastida)

What is the difference between a phylogenetic tree and a cladogram?

Cladograms and phylogenetic trees show relatedness, but phylogenetic trees also show how they are arranged according to time

Compare/contrast classification with systemization

Classification is grouping organisms that possess a common feature, but systematization is grouping organisms based on common evolutionary origin.

What are the practical uses of DNA bar coding?

Identifies organisms to the species level using gene sequence information (living animals, museum specimen, zoos, aquaria, fish markets, etc)

What are five major rank-free taxa above the phylum level in animal taxonomy?

Bilateria, Protostome, Lophotrochozoans, Ecdysozoa, Deuterostomia

List the distinguishing features of the Apicomplexa. List some examples of Apicomplexa parasites that affect human health.What are the vectors for Plasmodium parasite? What are the stages of the Plasmodium life cycle?

Alveoli have structural functions Apical complex -- used to penetrate host cells Examples: 1. Taxoplasma gondii - infects cats as well as humans, other mammals, and birds; 1/3 humans have tissue cysts of parasite - toxoplasmosis 2. Plasmodium - best known coccidian that causes malaria The vectors of plasmodium are Anopholes or Culex mosquitos 1. Mosquito bites human and sporozoite form goes into blood stream and infects liver cells 2. Undergoes asexual reproduction into the form of merozoites. 3. Merozoites burst out of liver cells and infects blood cells as amoeboid trophozoites. **when ur sick 4. Some form into gametocytes and the next mosquito to take a bit takes these up 5. In mosquito guts, gametocytes mature into gametes and are fertilized to form oocysts which grow and infects next human bitten again

What are the three forms exhibited by the Heterolobosea Naegleria fowleri? What form is the infective, feeding stage? What human disease results from a Naegleria fowleri infection?

Amebic, flagellated, and cyst stages Amebic trophozoite stage is the infective, feeding stage Results in amebic meningoencephalitis (PAM) "brain-eating amoeba"

Hydrogenosomes

Analogous to mitochondria; can make hydrogen without oxygen generate ATP anaerobically and release H2)

What groups are included within the Opisthokonta?

Animals, fungi, and some unicellular taxa Choanoflagellates

What prokaryotic domain is most closely related to the Eukarya?

Archaea similar biochemical features such as gene expression

What are the 3 domains of life? How were these taxonomic units determined?

Archaea, Bacteria, and Eukarya Determined by rRNA sequence difference

Describe the different strategies for both types of reproduction.

Asexual 1. Binary/multiple fission - splits into 2 or more equal size offspring 2. Budding - offspring arises from outgrowth of parent, smaller Sexual 1. Conjugation - exchange of gamete nuclei between two cells 2. Syngamy - fertilization of gametes to form zygotes

List and describe the various structural elements of the cytoskeleton including constituent proteins, functions, and stability.

Cytoskeleton functions in cell support, motility, and maintaining cell shape 1. Intermediate filaments are made of keratin and other proteins 2. Microtubules are made of tubulin proteins 3. Actin filaments are made of actin proteins (smallest) 4. Assemble and break apart quickly

Define symbiosis and list/describe 3 different symbiotic relationships providing a specific example for each type of symbiosis.

Different species living together (~10,000 do this) i. Mutualistic - both species benefit +/+ a. Ex. Zooxanthellae provide food for clam but get shelter ii. Commensilistic - one species benefits, the other species neutral +/+/- a. Ex. Mites attach to beetle host to aid in migration to more suitable habitat iii. Parasitic - one species benefits, other species harmed +/- a. Ex. Entamoeba infects intestinal system causing amoebic dysentery making host loose water etc.

List in order from most inclusive to least inclusive the Linnean taxonomic hierarchy of classification.

Domain, Kingdom, Phylum, Class, Order, Family, Genus, Species

What is a cyst? How does it ensure survival of a species?

Dormant forms with resistant outer coverings they can go into this stage under harsh conditions

Trichocysts

Elongated, cylindrical bodies that can discharge a spine like structure

What are the 3 clades within the Euglenozoa? What is their common feature?

Euglenids, Kinetoplastans, and Diplonemids All have pellicle - microtubles and proteins under plasma membrane allowing flexibility

In which domain would Kingdom Animalia be classified and why?

Eukarya, because they are multicellular?

Give some examples of Kinetoplastans, the diseases they cause in humans, and the vectors that transmit the kinetoplastan pathogen.

Examples - 1. Trypanosoma - genus of kinetoplastans that inhabit the blood of fish, amphibians, birds, reptiles, and mammals a. Some species transmitted by tsetse flies cause African Sleeping Sickness in humans and related diseases in domestic animals b. Some species transmitted by kissing bugs cause chagas disease in Central and South America 2. Leishmania species cause leishmaniasis in humans and are transmitted by sandflies (skin lesions, visceral ailments)

List some examples of Ciliophora. What structures do the Ciliphora use for protection, procuring prey, and feeding? What type of locomotive structures are used by ciliophorans?

Examples - Ick** Stendor Didinium (barrel-shaped ciliate that commonly feeds on paramecia) Protection - trichocysts with thorn like structures Prey - heterotrophic with cytostome (mouth), Trichocysts (expel threadlike structure) and toxicysts (expel a toxin to paralyze prey) Feeding - cilia Locomotive - cilia Alveoli produce pellicles, Free-living and parasites of fish ("ick"), mammals, frogs/toads, and invertebrates

What type of locomotor structure is exhibited by Heterolobosea? What is the trigger for the transformation from one form to another?

Flagella transforms when food resources are depleted

Contrast the Foramnifera with the Radiolarians in terms of pseudopodia, test components, and habitat

Foramnifera has reticulopodia while radiolarians have axopodia Foramnifera have porous tests of CaCO3 or silica while radiolarians have symmetrical silica tests. Both are marine Formanifera can be planktonic (drifting) but most are benthic (stationary)

Cilia

Hairlike projections that extend from the plasma membrane and are used for locomotion

What are the characteristics of the Cercozoa? What important fishery is plagued by Haplosporidium?

Heterogenous in morphology, motility, and nutrition Oysters

Phagotrophs

Heterotrophic protists that feed by ingesting particles

Contrast a homology with a homoplasy.

Homology described traits that evolved from a common ancestor while homoplasy does not

Characterize the traits of the Dinoflagellata including locomotive structures, nutrition strategy, protective covering, and symbiotic relationships.

Locomotive structures - 2 armored flagellates in grooves Nutrition strategy - 1/2 are photoautotropic with chloroplasts, 1/2 are heterotrophic Protective covering - naked or covered by cellulose plates Symbiotic relationships - 1. Zooxanthallae live in mutualistic symbiosis with corals, anemones, and clams producing sugars 2. Pfiesteria piscicida release a toxin in response to feces from schooling fish Causes "RED TIDE"....Freshwater or marine, alveoli produce plates, considered most important primary producers globally,

What is the locomotor organ of Diplomonads? What is their habitat? Give a familiar example of a diplomonad describing its structure and life cycle.

Locomotor structure - flagella Habitat - vertebrate digestive tracts i. commensals or parasites; anaerobic ii. Mitochondria absent (or reduced), but probably due to a secondary loss Examples - Giardia - a diplomonad that parasitizes humans, other mammals, amphibians, and birds; transmitted via cysts in feces

What is the locomotor structure of Parabasilids? What do Parabasilids use to generate ATP without oxygen? Give 2 examples of Parabasilids describing their structure and niche.

Locomotor structure - multiple flagellates with axostyle (rod composed of microtubules) Generate ATP without oxygen by using hydrogenosomes (generate ATP anaerobically and release H2) Examples - i. Trichomonas vaginalis is a human vaginal parasite (STD) ii. Trichonymphas are important symbionts in termite guts (have bacteria that digest cellulose, example of 3-level symbiosis)

What are the roles of the macronucleus and micronucleus? What types of reproduction are demonstrated by the Ciliophora?

Macronucleus - house keeping functions Micronucleus - sexual reproduction Reproduce by binary fission (until a limit and the sexual?)

Intermediate filaments

Made of keratin and other proteins

Saprozoic (osmotrophs)

Obtaining nourishment by absorption of dissolved organic and inorganic materials - decaying

What protozoan shares a termite gut with bacteria?

Parabasilids - trichonymphas

By what mechanism do Entamoeba feed? How are they transmitted from one organism to another? What is the infective stage?

Parasites of animals that kill and feed on host cells through trogocytosis (ingest "bites" of cell) Transmitted by durable cyst that forms during harsh conditions The infective stage is this cyst

Why are unicellular eukaryotes not considered animals?

They do not have all of the characteristics necessary

Describe the distinguishing flagella of the Stramenopiles. Give a few examples from the clade.

They have heterokont flagellates - 2 flagella, forwards one is long and hairy and trailing one is short and smooth Examples - 1. Oomycetes; one genus, Phytophthora, causes potato blight, superficially resembles fungus (Irish potato famine) 2. Heliozoans with testate amebas with axopodia (body form evolved several different times) 3. phytoplankton with silica cell walls (forms DE)

How does a unicellular eukaryote function within the constraints of a single cell?

They have structural complexity because of symbiogensis (mitochondria and chloroplasts)

Describe the process for naming taxa based on binomial nomenclature

Two-naming system with capitalized genus and a lower-case species with both names italicized or underlines

Lysosomes

cell organelle filled with enzymes needed to break down certain materials in the cell

Paraphyletic

consists of an ancestral species and some, but not all, of its descendants

Polyphyletic

contains some members that don't share a common ancestor

Smooth Endoplasmic Reticulum

creates lipids or fat