Bio 2 FIrst Test Brinner

Ectomycorrhizae

("outside" mycorrhiza) depend on fungi enveloping the roots in a sheath (called a mantle) and a Hartig net of hyphae that extends into the roots between cells

virus structure

(smaller than bacteria) Viruses are obligate intracellular parasites that do not themselves possess a cell. They are, essentially, chemical complexes of RNA or DNA protected by protein. A virus particle (outside host) can also be referred to as a virion.

influenza virus

3 major types of flu virus (A< B< and C), only Type A can occur in human, other mammals, and birds; the flu subtype is determined by the kinds of proteins representing the H and N protein spikes making up the capsid of the virus; different strains of the virus requires different vaccines; genetic high mutation rates is primarily responsible for the high diversity in strains; genetic recombination between flu strains from different species is common

3. In malaria, Plasmodium falciparum grow inside of which human cells? A. Liver and red blood cells B. Liver cells C. Red blood cells D. Intestinal cells E. Liver and intestinal cells

A. liver and red blood cells

4. Bacterial cells pick up free pieces of DNA from the medium-pieces that were released from dead bacteria-in a process called A. transformation. B. transduction. C. conjugation. D. infection. E. replication.

A. transformation

Euglenozoa

Among the earliest eukaryotes to possess mitochondria 1/3rd have chloroplasts and are autotrophic May become heterotrophic in the dark Others lack chloroplasts and are heterotrophic All have a flexible pellicle No sexual reproduction

outgroup

An outgroup is an organism that is considered not to be part of the group in question, but is closely related to the group. The evolutionary conclusion from this is that the outgroup branched from the parent group before the other two groups branched from each other.

Mutualistic Relationships

Arthropods depend on the fungus for protection from predators and pathogens, while the fungus obtains nutrients and a way to disseminate spores into new environments. The association between species of Basidiomycota and scale insects is one example.

4. The mitochondria of eukaryotic cells most likely arose as a result of endosymbiosis between a eukaryotic cell and a A) blue-green alga. B) nonsulfur purple bacterium. C) red alga. D) cyanobacterium.

B. nonsulfur purple bacterium

4. The principle of parsimony suggests that: A) neutral mutations occur at a fairly constant rate over time. B) the most accurate phylogenetic tree is the one with the most tips. C) species grouped into larger taxa for a cladogram should be from a single clade for the results to be reliable. D) the preferred hypothesis is the one that is the simplest. E) None of the above accurately describes the principle of parsimony.

D. preferred hypothesis is the simplest

Recently a class of infectious proteins with no associated nucleic acid have been identified. They are referred to as A. bacteriophages. B. latent viruses. C. viroids. D. prions. E. virions.

D. prions

2. The response of bacteria that allows them to be identified as Gram-positive or negative is due to A. the type of DNA or RNA they contain. B. their ability or lack of ability to fix nitrogen. C. whether they are aerobic or anaerobic. D. whether their cell walls have a thin or thick layer of peptidoglycan. E. the rRNA sequences they demonstrate.

D. whether their cell walls have a thin or thick layer of peptidoglycan

Beneficial bacteria

Decomposers play an important role in the environment. Decomposition differences between a fish caught in Canada and Florida when put on ice???

apomorphy

Derived trait.

1. The parasite that is responsible for causing malaria is called A. Streptococcus. B. Chlamydomonas. C. Plasmodium. D. Entamoeba. E. Giardia.

C. plasmodium

7. The science of describing, naming, and classifying extant and extinct organisms is A. evolution. B. phylogeny. C. taxonomy. D. nomenclature. E. biology.

C. taxonomy

5. The protists are a paraphyletic group that have traditionally been grouped together because A) they are all genetically similar to each other. B) they all have very similar morphological characters. C) they are not fungi, animals, or plants. D) they all have similar nutritional modes and live in similar environments.

C. they are not fungi, animals, or plants

8. Which of the following would be homologous structures? A. the wing of a bird and the wing of a bee B. the wing of a bee and the wing of a bat C. the wing of a bat and the arm of a human D. All of these answers are correct.

C. wing of a bat and arm of human

Habitat

Chytrids are found primarily in aquatic environments. Other fungi, such as Coccidioides immitis, which causes pneumonia when its spores are inhaled, thrive in the dry and sandy soil of the southwestern United States. Fungi that parasitize coral reefs live in the ocean. However, most members of the Kingdom Fungi grow on the forest floor, where the dark and damp environment is rich in decaying debris from plants and animals.

Brown algae

Conspicuous seaweeds of northern regions

1. The three shapes of bacteria are A. haplontic, diplontic, and alternations. B. anaerobic, aerobic, and facultative. C. heterotrophic, autotrophic, and chemosynthetic. D. bacillus, coccus, and spirillum. E. helical, spiral, and streptococci.

D. bacillus, coccus, and spirillum

6. Many researchers who study the kingdom Protista argue that all of these organisms should not be placed in the same kingdom, because these organisms could not have evolved from a common ancestor. In other words, they argue that the kingdom Protista is _____. A. polyphyletic B. paraphyletic C. monophyletic D. heterophyletic E. none of the above

D. heterophyletic

Can a virus be killed? A. Yes, destroying its genome kills it. B. No, viruses are capable of self-assembly and cannot be permanently killed. C. Yes, separating the genes from the capsid kills it. D. No, viruses are non-living and cannot die.

D. no viruses are nonliving and cannot die

2. Which one of the following do all three domains of life have in common? A) the same genetic code B) plasma membranes C) glycolysis D) (A) and (C) E) (A), (B) and (C)

E. ABC

6. Which one of the following statements about protists is incorrect? A) Protists are most commonly found in moist environments. B) Protists are eukaryotic organisms. C) The organism that causes malaria is a protist. D) At least half of the oxygen in the atmosphere is produced by protists. E) All of the above statements about protists are correct.

E. all of the above

1. The evolutionary history of a species or group of species is most accurately referred to as: A) systematics. B) ontogeny. C) taxonomy. D) bioinformatics. E) phylogeny.

E. phylogeny

5. A __________ taxon consists of members of several evolutionary lines and does not include the most recent common ancestor of the included lineages.A) parsimonious B) paraphyletic C) monophyletic D) chronophyletic E) polyphyletic

E. polyphyletic

6. Which of the following is considered to be noncellular? A. bacteria B. fungi C. algae D. protozoans E. viruses

E. viruses

domains

Eukarya, Archaea (small, single celled, cell wall, no nucleus, can live in extreme conditions) , Bacteria (greatest # niches) Kingdoms of Plantae, Fungi, Animalia and Protista are all in the Eukarya Domain - What are the main derived characters (synapomorphy) that differentiates these kingdoms? Consider: The traits that all 3 domains have in common are hypothesized to be the result of all 3 domains evolving from a common prokaryotic ancestor. Those traits are that all species use the same genetic code (very few exceptions), plasma membranes, and glycolysis.

ciliates

Feature large numbers of cilia arranged in longitudinal rows or spirals around the cell

Multicellularity

From single cells to colonies to true multicellularity Arisen multiple times Fosters specialization Few innovations have had as great an influence on the history of life

Fungivores

Fungal spores are rarely completely degraded in the gastrointestinal tract of an animal, and many are able to germinate when they are passed in the feces. Some dung fungi actually require passage through the digestive system of herbivores to complete their lifecycle. The black truffle—a prized gourmet delicacy—is the fruiting body of an underground mushroom.

saprobes

Fungi are mostly saprobes (saprophyte is an equivalent term): organisms that derive nutrients from decaying organic matter. They obtain their nutrients from dead or decomposing organic matter: mainly plant material. Fungal exoenzymes are able to break down insoluble polysaccharides, such as the cellulose and lignin of dead wood, into readily absorbable glucose molecules.

ergosterol

Fungi have plasma membranes similar to other eukaryotes, except that the structure is stabilized by ergosterol: a steroid molecule that replaces the cholesterol found in animal cell membranes.

Reproduction

Fungi reproduce sexually and/or asexually. Perfect fungi reproduce both sexually and asexually, while the so-called imperfect fungi reproduce only asexually (by mitosis). Fungi reproduce asexually by fragmentation, budding, or producing spores. Fungi play a crucial role in the balance of ecosystems. They colonize most habitats on Earth, preferring dark, moist conditions. They can thrive in seemingly hostile environments, such as the tundra, thanks to a most successful symbiosis with photosynthetic organisms like algae to produce lichens. Fungi are not obvious in the way large animals or tall trees appear. Yet, like bacteria, they are the major decomposers of nature. With their versatile metabolism, fungi break down organic matter, which would not otherwise be recycled.

Environment

Fungi thrive in environments that are moist and slightly acidic, and can grow with or without light. They vary in their oxygen requirement. Most fungi are obligate aerobes, requiring oxygen to survive. Other species, such as the Chytridiomycota that reside in the rumen of cattle, are are obligate anaerobes, in that they only use anaerobic respiration because oxygen will disrupt their metabolism or kill them. Yeasts are intermediate, being faculative anaerobes. This means that they grow best in the presence of oxygen using aerobic respiration, but can survive using anaerobic respiration when oxygen is not available.

Shapes

Helical (usually plant viruses) Icosahedral with or without an envelope (usually animal viruses) Complex binary (infects bacteria)

character state

In cladistics, one of two or more distinguishable forms of a character, such as the presence or absence of teeth in amniote vertebrates

Phagotropic

Ingest particle food

Osmotrophic

Ingest soluble food

Protists

Kingdom includes all eukaryotes (such as protozoa, some algae, water molds, slime molds, etc) except green plants, animals and fungi (allows them to be classified into one kingdom)....most diverse of four eukaryotic kingdoms, not monophyletic ( means that all protists are not more closely related to each other than they are to some other kinds of organisms); majority reproduce asexually most of the time, but under stress conditions will reproduce sexually. Most are small (microscopic) but some are huge (100 meters). Note: Some algae are not considered plants because they lack plant structures such as roots and placed among Protists. Green algae are now grouped with plants.

Eukaryotes

Major differences between prokaryotes and eukaryotes: cytoskeleton and compartmentalization (membrane bound nucleus and organelles). Understand the origin including primary and secondary endosymbiosis. Note: How do we know that endosymbiosis really occurred?How did these evolution events help eukaryotes?

2 types of nuclei

Micronucleus without will reproduce asexually Macronucleus essential for function Have two types of vacuoles

Hyphae/ mycelium

Most fungi are multicellular organisms. They display two distinct morphological stages: the vegetative and reproductive. The vegetative stage consists of a tangle of slender thread-like structures called hyphae (singular, hypha), whereas the reproductive stage can be more conspicuous. The mass of hyphae is a mycelium. It can grow on a surface, in soil or decaying material, in a liquid, or even on living tissue.

spores

Most fungi produce a large number of spores, which are haploid cells that can undergo mitosis to form multicellular, haploid individuals.

Parabasalids

Not included in exam 1.

Green Algae

Only once in evolution these algae gave rise to all land plants. Have 2 monophyletic groups: Chlorophyta and charophytes. Diverged from land plants over 1BYA. Can be single cell, multicellular or colonial.

Fungal Parasites and Pathogens

Parasitism describes a symbiotic relationship in which one member of the association benefits at the expense of the other. Both parasites and pathogens harm the host; however, the pathogen causes a disease, whereas the parasite usually does not. Commensalism occurs when one member benefits without affecting the other.

diatoms

Photosynthetic, unicellular organisms Unique double shells made of silica

Dinoflagellates

Photosynthetic, unicellular with flagella Live in aquatic environments Some are luminescent Do not appear to be directly related to any other phylum Major Cause of "Red tide" which are "blooms" that kill - fish, birds, and marine mammals may die from toxins

protistan nutrition

Phototrophs, Heterotrophs and Mixotrophs.

Science

Production of knowledge!!!

Mycology

Progress in the field of fungal biology was the result of mycology: the scientific study of fungi.

Apicomplexans

Spore-forming animal parasites Apical complex is a unique arrangement of organelles at one end of the cell which enables the cell to invade its host. Plasmodium causes malaria. Symptoms include chills and fever usually in late afternoon. Complex life cycle - sexual, asexual, different hosts. Eradication focused on eliminating mosquito vector, drug development, vaccines.

Scientific Method

Technique used worldwide to produce knowledge. Question-Background research-Hypothesis-experiment to test hypothesis- analyze results then accept or reject hypothesis.

Microbiome

The full array of microorganisms (the microbiota) that live on and in humans and, more specifically, the collection of microbial genomes that contribute to the broader genetic portrait, or metagenome, of a human. The genomes that constitute the human microbiome represent a remarkably diverse array of microorganisms that includes bacteria, archaea, fungi, and even some protozoans and nonliving viruses. Bacteria are by far the most numerous members of the human microbiome: the bacterial population alone is estimated at between 75 trillion and 200 trillion individual organisms, while the entire human body consists of about 50 trillion to 100 trillion somatic (body) cells.

mycorrhizae

The roots of the plant connect with the underground parts of the fungus forming mycorrhizae. Through mycorrhizae, the fungus and plant exchange nutrients and water, greatly aiding the survival of both species. Mycorrhiza, which comes from the Greek words myco meaning fungus and rhizo meaning root, refers to the association between vascular plant roots and their symbiotic fungi.

Yeast

The vegetative body of a fungus is a unicellular or multicellular thallus. Dimorphic fungi can change from the unicellular to multicellular state depending on environmental conditions. Unicellular fungi are generally referred to as yeasts. Saccharomyces cerevisiae (baker's yeast) and Candida species (the agents of thrush, a common fungal infection) are examples of unicellular fungi

Characteristics of Fungi

They are a polyphyletic group of organisms that share characteristics, rather than sharing a single common ancestor.

prokaryote modern classification

based on sequencing of proteins, DNA and RNA

facultative aerobes

can use oxygen or not

Dutch elm disease

caused by the fungus Ophiostoma ulmi, is a particularly devastating type of fungal infestation that destroys many native species of elm (Ulmus sp.) by infecting the tree's vascular system. The elm bark beetle acts as a vector, transmitting the disease from tree to tree. In humans, fungal infections are generally considered challenging to treat. Unlike bacteria, fungi do not respond to traditional antibiotic therapy, since they are eukaryotes. Fungal infections may prove deadly for individuals with compromised immune systems.

virulent virus

causes lysis of their hosts (lytic); Consider: (Refer to illustration below) A virulent virus is one that infects the host cell and enters into the lytic stage causing replication of virus and lysis of the host cell to release these produced viruses. A temperate virus is one that can incorporate its genome into the host cell's genome and remain dormant, only reproducing as the host cell reproduces itself (lysogenic stage). But the virus genome can become activated and it can enter a lytic stage. NEW INFO added 5/14/2012

prokaryotes differing from eukaryotes

cell size, multicellularity, chromosomes, organelles, reproduction Note: Eukaryotes and Prokaryotes both have ribosomes.

ancestral characteristics

characteristics that have arisen in organisms as a result of common evolutionary descent

choanoflagellates

filter bacterial food from the water through the collars on the cells; structure similar to one on sponges Propulsion by a single posterior flagellum Consider: Choanoflagellates are the group of protists with similarities to sponges and other animals, including humans.d

Glomeromycete fungi

form vesicular-arbuscular interactions with arbuscular mycorrhiza (sometimes called endomycorrhizae).

E. coli

found in the lower intestine of warm blooded animals; 5000 genes, help host by producing vitamin K2 Consider: TB, cavities and several STDs caused by bacteria.

Importance of Fungi in Human Life

fungi help to control the population of damaging pests. they are part of the nutrient cycle in ecosystems. The mycorrhizal relationship between fungi and plant roots is essential for the productivity of farm land. We also eat some types of fungi.

transformation

genetic alteration of a cell's genome by the introduction of foreign DNA

spike

glycoproteins that project from some enveloped viruses allowing for attachment of the virus to the targeted host cell, are measured in the nm range

cyanobacteria

group of bacteria that produced oxygen and changed the Earth's atmosphere from an anoxic one to one rich in oxygen

Psilocybe semilanceata and Gymnopilus junonius

have been used for their hallucinogenic properties by various cultures for thousands of years.

prokaryote structure (bacteria)

have cell walls consisting of a network of polysaccharides connected by cross links of polypeptides (peptidoglycan) flagella used for movement have enzymes used for cellular respiration attached to cell membrane have 3 shapes (due to cell walls): bacillus, coccus, and spirillum can form biofilms

retrovirus

have the enzyme reverse transcriptase, high error rate of reverse transcriptase leads to high genetic diversity of HIV; this in turn creates difficulty in creation of vaccine direction of genetic information transfer in a retrovirus (such as HIV) is RNA to DNA to mRNA to protein

lytic cycle

host cell lyses, releasing many viral particles

homoplasy

in cladistics, a shared character state that has not been inherited from a common ancestor exhibiting that state; may result from convergent evolution or evolutionary reversal. The wings of birds and of bats, which are convergent

symplesiomorphy

in cladistics, another term for a shared ancestral/primitive or outgroup character state (I remember this by saying the primitive trait is the most symplesiomorphy)

plesiomorphy

in cladistics, another term for an ancestral character state

polarize

in cladistics, to determine whether character states are ancestral or derived

polyphyletic

in phylogenetic classification, a group that does not include the most recent common ancestor of all members of the group

monophyletic

in phylogenetic classification, a group that includes the most recent common ancestor of the group and all its descendants. A clade is a monophyletic group.

paraphyletic

in phylogenetic classification, a group that includes the most recent common ancestor of the group, but not all its descendants

synapomorphy

in systematics, a derived character that is shared by clade members; best mechanism to analyze the evolutionary sequence in the development of a complex character (I remember this by saying the derived (new) characters are synapy...synapomorphy)

core

inner most portion is made of DNA or RNA

lysogenic cycle

integration and stabilizing of viral genes into the host cell's genome

Life cycle

involves alternation of generations

Mycotoxicosis

is the poisoning of humans (and other animals) by foods contaminated by fungal toxins (mycotoxins).

protistan cysts

may arise from sexual or asexual reproduction; facilitate spread of pathogens from one host to another and consumption can lead to human health problems

cancer

may be caused by viruses through triggering the expression of cancer-causing genes present in the genome

prion

misshapen protein agents with no associated nucleic acid that may convert other proteins in the cell to also become these agents causes Mad-cow disease and other related diseases

amoebae

move by pseudopodia extension

Sporophyte

multicellular and diploid

Gametophyte

multicellular and haploid

reproductive isolation

not being able to mate outside one's group

exchange of genetic material via horizontal transfer

occurs through conjugation (depends on presence of conjugative plasmids when genes are transferred through rigid, tubular sex pili), transduction (occurs when viruses (bacteriophage) package host DNA and transfer it upon subsequent infection), transformation (bacterial cells pick up free pieces of DNA from the medium-pieces that were released from dead bacteria), and exchange of R plasmids (plasmids are different from bacterial chromosomes in that plasmids have few genes, bacterial chromosome have many)

Fermentation

of grains to produce beer, and of fruits to produce wine—is an ancient art that humans in most cultures have practiced for millennia.

obligate anaerobe

organisms poisoned by oxygen

capsid

outer layer composed of protein subunits; protein on surface can interact with a protein on the surface of the host cell nucleic acid

prophage

parasitic viral DNA that has been integrated into the chromosome of its bacterial host

Protista

polyphyletic paraphyletic group or organisms that do not fit within Animalia, Plantae, or Fungi

gram-positive Vs gram-negative

positive bacteria have a thicker peptidoglycan wall with small amounts of teichoic and lipoteichoic acid and will stain a purple color... gram-negative contain lipopolysaccharides, less peptidoglycan and no acids and do not retain the purple-colored dye; differences in cell's wall determines outcome of the Gram stain lipopolysaccharides in the outer membrane of certain bacteria make them more resistant to penicillin

envelope

possessed by some viruses; are a lipid membrane (derived from a host-cell membrane) that is rich in lipoproteins and glycoproteins (generally virally encoded) surrounding virus capsid

principle of parsimony

principle state that scientists should favor the hypothesis that requires the fewest assumptions; simplest phylogenetic tree should be chosen

protistan structures found on various members

pseudopodia (amoeboids) - movement and feeding cyst - protective outer covering on dormant cell flagella (zooflagellates) - propel the organism, collect food, and propel reproductive cells cilia (ciliates) - propulsion and feeding

Contractile vacuoles

regulation of water balance

binary fission

reproductive process that produces identical cells by simple splitting

obligate aerobes

requires oxygen

foraminiferans

resemble tiny snails; have shells called tests composed of organic materials reinforced with grains of inorganic matter; their tests help make up many limestone deposits including the White Cliffs of Dover

Leishmaniasis

sand fly- cause severe lesions

Chagas disease

skin contact with urine or blood of infected wild animal. Heart affected by parasite and increases in size.

protistan mechanisms

slimy or hard protective coverings, toxins, sharp projectiles, bioluminescence, and/or spines

tissue tropism

targeting of specific range of cells within suitable organism

Fungi

taxa with a cell wall, external digestion, and lacking photosynthesis capability

biological species concept (BSC)

the concept that defines species as groups of populations that have the potential to interbreed and that are reproductively isolated from other groups

phylogenetic species concept (PSC)

the concept that defines species on the basis of their phylogenetic relationships

phylogeny

the evolutionary history of an organism, including which species are closely related and in what order related species evolved; often represented in the form or an evolutionary tree that are constructed based on morphological analysis, DNA sequences, and geographical information Consider: Phylogenetically based taxonomy helps us learn about traits in organisms using information in related species. These traits can also include physiology, development, and behavior.

convergent evolution

the independent development of similar structures in organisms that are not directly related; often found in organisms living in similar environments

systematics

the reconstruction and study of evolutionary relationships (phylogenies)

induction

the switch from a lysogenic prophage to a lytic cycle

viroids

they are tiny, naked molecules of RNA a few hundred nucleotides long whose sequence resembles intron sequences in rRNA genes; they are causative agents of plant diseases

fungi are heterotrophs

they use complex organic compounds as a source of carbon, rather than fix carbon dioxide from the atmosphere as do some bacteria and most plants. In addition, fungi do not fix nitrogen from the atmosphere. Like animals, they must obtain it from their diet. However, unlike most animals, which ingest food and then digest it internally in specialized organs, fungi perform these steps in the reverse order; digestion precedes ingestion.

endospores

thick-walled structures that contain chromosome and small amount of cytoplasm...these are formed in response to environmental stress (e.g., low nutrients)

nitrogen fixation and use

this pathway begins with atmospheric nitrogen ( Dinitrogen; unusable by plants in this form because of strength of N-N triple bond), bacterial nitrogenase(enzyme that catalyzes the reactions); ammonia; conversion by plants or algae; synthesis of proteins

Pellicle

tough but flexible outer covering

horizontal gene transfer

transfer of genes between different species, both prokaryotic or eukaryotic

African sleeping sickness

tsetse fly

emerging virus

virus in a new host with a potential lethality rate in excess of 50%; example is Ebola virus; these viruses are able to jump from one species to another; hantavirus originates in deer mice and causes hemorrhagic-type fever; SARS is completely new form of corona virus

latent virus

virus is able to hide from host's immune system by integrating itself into the host cell's genome and not producing new viruses...e.g., chickenpox may be followed, years later, with shingles with both the result of the same viral infection

bacteriophages

viruses that can infect bacteria

HIV

each HIV particle has a glycoprotein on its surface, called gp120, that fits a cell-surface marker protein called CD4 on the surfaces of the immune system cells called macrophages and T cells; this virus is closely related a chimpanzee virus

viral reproduction

entry into host because portions of capsid adhere to specific receptor on host Cell's outer surface...viral nucleic acid enter hose cell and codes for protein units inside capsid...takes over metabolic machinery of host cell Consider: Reproduction occurs through the following stages: attachment, penetration, biosynthesis (assembly), maturation, and release.

Rhizobium

example of a diazotrophs (nitrogen fixing bacteria)...only organisms (bacteria group) capable of taking gaseous nitrogen and combining it with hydrogen to make ammonia

taxonomy

field of biology concerned with classifying organisms and viruses; accepted pattern is Domain, Kingdom, Phylum, Class, Order, Family, Genus, Species (do kings play chess on fine green sand) Consider: Each taxa, as the hierarchical order descends, has a smaller number of species. So Order, Family, and Genus would have fewer species than Class.

prokaryote facts

1) oldest organisms on Earth with fossils ~3.5 billion years old 2) structurally simplest organisms 3) most abundant life forms on earth 4) 90-99% unknown and undescribed. 5) lack a membrane bound nucleus and other organelles or cell inclusions. 6) Lack of cell compartments. 7) Include 2 domains Bacteria and Archaea. Consider: Archaea and Eukarya share nucleic acid similarities so Eukarya split off from Archaea

bacteria differing from Achaea

1. cell wall composition 2. plasma membrane make-up 3. DNA replication 4. gene expression 5. Bacteria have peptidoglycan which Archae lack. Consider: Archaea are able to live in the most extreme environments.

prokaryotic metabolism

1. photoautotrophs carry out photosynthesis (cyanobacteria use chlorophyll 2. chemolithoautotrophs - energy through oxidizing inorganic substances (nitrifiers oxidize ammonia or nitrite to obtain energy, producing nitrate that is taken up by plants) 3. photoheterotrophs - purple and green nonsulfur bacteria use light as energy source and carbon from organic molecules 4. chemoheterotrophs - obtain both carbon atoms and energy from organic molecules (humans)

Kinetoplastids

2nd major group in Euglenozoa Unique, single mitochondrion DNA maxicircles and minicircles Trypanosomes cause human diseases

Animal and Human Parasites and Pathogens

A mycosis is a fungal disease that results from infection and direct damage. Fungi attack animals directly by colonizing and destroying tissues.

9. A paraphyletic group contains A. a common ancestor but not all of its descendants. B. groups of species with different common ancestors. C. a common ancestor and all of its descendants. D. a common ancestor and all of its descendants but not the most recent common ancestor. E. every species ever derived from a common ancestor

A. common ancestor but not all its descendants

Cell Structure

As eukaryotes, fungal cells contain a membrane- bound nucleus. The DNA in the nucleus is wrapped around histone proteins, as is observed in other eukaryotic cells. A few types of fungi have structures comparable to bacterial plasmids (loops of DNA); however, the horizontal transfer of genetic information from one mature bacterium to another rarely occurs in fungi. Fungal cells also contain mitochondria and a complex system of internal membranes, including the endoplasmic reticulum and Golgi apparatus. Unlike plant cells, fungal cells do not have chloroplasts or chlorophyll. Like plant cells, fungal cells have a thick cell wall. The rigid layers of fungal cell walls contain complex polysaccharides called chitin and glucans. Chitin, also found in the exoskeleton of insects, gives structural strength to the cell walls of fungi. The wall protects the cell from desiccation and predators. Most fungal hyphae are divided into separate cells by endwalls called septa (singular, septum). In most phyla of fungi, tiny holes in the septa allow for the rapid flow of nutrients and small molecules from cell to cell along the hypha. They are described as perforated septa. The hyphae in bread molds (which belong to the Phylum Zygomycota) are not separated by septa. Instead, they are formed by large cells containing many nuclei, an arrangement described as coenocytic hyphae.

7. Which one of the following is not a basic type of protist nutrition? A) osmotrophy B) mixotrophy C) autotrophy D) chemotrophy E) phagotrophy

B. mixotrophy

3. In a cladistic approach to phylogeny, a trait shared with a distant common ancestor is referred to as a(n): A) symplesiomorphy. B) ingroup. C) synapomorphy. D) outgroup. E) shared derived character.

B. Ingroup

3. Which type of organism will form endospores when faced with unfavorable environmental conditions? A. viruses B. bacteria C. algae D. protozoans E. fungi

B. bacteria

Flu shots are vaccines against the most common strains of the flu virus. Most vaccines are rarely changed but new flu vaccines are produced every year. Why are flu shots constantly being reformulated? A. The flu virus is not completely known. B. Certain parts of the viral genome are reshuffled by mutations and recombination. C. The virus mixes with prions. D. The virus shifts from RNA to DNA.

B. certain parts of the viral genome are reshuffled by mutations and recombination

The HIV virus is considered a(n) ______ virus, because after getting integrated into the host cell chromosomes, it does not begin replicating immediately. A. phage B. latent C. transforming D, benign E. inducible

B. latent

5. What is the evolutionary relationship among Archaea, Bacteria, and Eukarya? A. Since Archaea are the most primitive, Archaean ancestors gave rise to bacteria that in turn gave rise to eukaryotes. B. All three domains are equally distant from the most primitive common ancestor, a protocell. C. Archaea and Eukarya share nucleic acid similarities so Eukarya split off from Archaea. D. Bacterial ancestors gave rise to both Archaea and to eukaryotes as two separate side branches. E. Archaea ancestors gave rise to both bacteria and to eukaryotes as two separate side branches.

C. archaea and eukarya share nucleic acid similarities

Viruses are characterized by all of the following except A. being found in every organism investigated so far. B. being specific to the hosts they infect. C. being capable of independent reproduction. D. being acellular.

C. being capable of independent reproduction

Why do viruses only infect specific types of cells? A. Viruses infect the first cells they encounter. B. If a host cell is weakened, viruses have an easier time infecting it. C. The host cells have the correct surface receptor that the virus can fit into. D. Viruses only attack epithelial cells, such as the cells lining the lungs. E. The initial choice is random but once a cell type is chosen it becomes the preferred host.

C. host cells have correct surface receptor that the virus can fit into

Decomposers and Recyclers

Trace elements present in low amounts in many habitats are essential for growth, and would remain tied up in rotting organic matter if fungi and bacteria did not return them to the environment via their metabolic activity. Fungi produce a variety of exoenzymes to digest nutrients. The enzymes are either released into the substrate or remain bound to the outside of the fungal cell wall. Large molecules are broken down into small molecules, which are transported into the cell by a system of protein carriers embedded in the cell membrane. Because the movement of small molecules and enzymes is dependent on the presence of water, active growth depends on a relatively high percentage of moisture in the environment.

symbiosis

Types of symbiotic relationship and influence on evolution. (Mutualism, Commensalism and Parasitism)

Diplomonads

Unicellular Move with flagella 2 nuclei Giardia (causes diarrhea) Lack mitochondria but have some mitochondrial genes in their DNA.

host range

Usually limited host range

Important human viruses

Virus Classification by genome structure and Core

derived character

a characteristic used in taxonomic analysis representing a departure from the primitive (ancestor) form; in cladistics, characteristics between the branch points of a cladogram that are shared by all organisms above the branch point and are not present in any below it Understand the difference between derived and ancestral characteristics.

cladogram

a graphical representation of possible evolutionary relationships, based on polarization of characters, in which taxa are placed at the tips, not at the branch points, of the phylogenetic tree and shared, derived characteristics common to taxa above the branch point are placed at the branch point. Helps with the studies in evolution, ecology, biogeography and even forensics. Consider: Steps to construct a cladogram would be 1. gather data on characters to be used, 2. establish the character states (teeth), 3. polarize the characters (ancestral or derived) 4. select an outgroup (closely related to but not a member) 5. apply principle of parsimony (hypothesis that requires the fewest assumptions)

clade

a group containing all descendants of a common ancestor

envelope

a layer of lipoprotein and glycoprotein that covers the outer surface of some viruses made from host

cladistics

a taxonomic technique used for creating hierarchies or organisms that represent true phylogenetic relationship and descent. This technique has multiple uses including the HIV court case.

lichens

are an association between a fungus and its photosynthetic partner (usually an alga). The body of a lichen, referred to as a thallus, is formed of hyphae wrapped around the photosynthetic partner. Can survive in the most unusual and hostile habitats. They become completely desiccated, and then rapidly become active once water is available again. The thallus of lichens grows very slowly, expanding its diameter a few millimeters per year. Both the fungus and the alga participate in the formation of dispersal units for reproduction. Lichens produce soredia, clusters of algal cells surrounded by mycelia. Soredia are dispersed by wind and water and form new lichens.

Antibiotics

are naturally produced by fungi to kill or inhibit the growth of bacteria, limiting their competition in the natural environment. Important antibiotics, such as penicillin and the cephalosporins, are isolated from fungi.

nucleoid region

area where prokaryotic DNA is found (no membrane)

Mycetismus

describes the ingestion of preformed toxins in poisonous mushrooms. In addition, individuals who display hypersensitivity to molds and spores develop strong and dangerous allergic reactions. Fungal infections are generally very difficult to treat because, unlike bacteria, fungi are eukaryotes. Antibiotics only target prokaryotic cells, whereas compounds that kill fungi also harm the eukaryotic animal host. Many fungal infections are superficial; that is, they occur on the animal's skin. Termed cutaneous ("skin") mycoses, they can have devastating effects. For example, the decline of the world's frog population in recent years may be caused by the chytrid fungus Batrachochytrium dendrobatidis, which infects the skin of frogs and presumably interferes with gaseous exchange. These fungi are often misnamed "dermatophytes", from the Greek words dermis meaning skin and phyte meaning plant, although they are not plants. Dermatophytes are also called "ringworms" because of the red ring they cause on skin.

Food vacuoles

digestion of food