CLASSIFICATION

All female mammals produce __________ Most mammals have ___________. Milk hair

The science of naming and classifying organisms.

taxonomy

Linnean taxonomy classifies organisms based on their ________ and _________ similarities.

physical structural

A group of organisms in a classification system is called a _________.

taxon

The basic taxon in the Linnean system is the _________.

species

A system that gives each species a two part scientific name using Latin words.

binomial nomenclature

The first part of the name of a species in binomial nomenclature is called a _______.

genus

One or more physically similar species that are thought to be closely related.

genus

Genus names are always _______ and in ______ or underlined. Species names are always _______ and are also ______ or underlined.

capitalized italics lowercase italics

The Linnean system of classification has seven levels or _______.

taxa

What are the taxa for the Linnean Classification system?

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

What is a limitation of the Linnean classification system?

His system focused on physical similarities alone. Comparing genetic traits is more accurate.

The evolutionary history for a group of species is called a _________.

phylogeny

The most common method used to make evolutionary trees is called_________.

cladistics

Classification based on common ancestry. cladistics

An evolutionary tree that proposes how species may be related to each other through common ancestry.

cladogram

A group of species that shares a common ancestor.

clade

Traits that can be used to figure out evolutionary relationships among a group of species that are shared by some species but are not present in others.

derived characters

Each place in a cladogram where a branch splits.

node

What is the difference between a clade and a taxon?

A taxon is a group of organisms classified together in a system such as that of Linneaus. A clade is any group of organisms that share a common ancestor, so it can contain many taxa of different levels.

Why does DNA often have the “last word” when scientists are constructing evolutionary relationships?

Shared or identical sequences of DNA is hard proof of common ancestry, whereas shared traits or similar characteristics can be the result of convergent evolution.

What was the method, proposed by Linus Pauling and Emile Zuckerkandl, of evolutionary time? (early 1960’s)

They compared the amino acid sequences of hemoglobin from a wide range of species. Their findings show that the more distantly related two species are, the more amino acid differences there are in their hemoglobin.

Models that use mutation rates to measure evolutionary time.

molecular clocks

Pauling and Zuckerkadl found that mutations tend to add up at a _________ _____ for a group of related species.

constant rate

How may a geologic event be related to a rate of mutation?

Geologic events may be the cause to separate or isolate a species. If the species is subjected to a different environment, different mutations may occur and the geologic event was the impetus for genetic differentiation.

Pauling and Zuckerkandl confirmed that the number of amino acid differences _________ with the evolutionary time between each group of species.

increases

Why is the comparison between amino acids in hemoglobin between species an important discovery?

The amino acid differences are greater the farther back one goes along the evolutionary history(timeline). Humans have 16 differences with mice, 18 with the horse, 35 with a bird, and 79 with a shark.

DNA found only in mitochondria. (mt DNA) Always inherited from the mother. (nuclear DNA is a combination of DNA from both parents)

mitochondrial DNA

A type of RNA useful for studying distantly related species, such as species that are in different kingdoms or phyla.

Ribosomal RNA rRNA

When studying the relationships among species over longer time scales, it is best to use a molecule that has a ___________ mutation rate.

lower

Who first used rRNA to establish that archaea diverged from the common ancestor they share with bacteria almost 4 billion years ago?

Carl Woese

How are molecular clocks used to measure evolutionary time?

The clocks presume that mutations occur at a constant rate for any clade or group of related taxa. Because these changes occur at a relatively constant and predictable rate, the changes can be used to measure how long ago different lineages diverged.

What are the benefits of mitochondrial DNA and ribosomal RNA as molecular clocks?

Mitochondrial DNA accumulates mutations relatively quickly, so it is most useful for analyzing relatedness within closely related species or change within a species. Ribosomal RNA has many conservative regions that accumulate mutations relatively slowly, so it is useful for studying taxa that are more distantly related.

What molecular clock might be useful to examine the evolutionary relationship between several phyla in the kingdom Plantae?

rRNA, because it accumulates mutations relatively slowly

Why did Woese propose classifying bacteria and archaea into separate domains, rather than just separate kingdoms?

The genetic difference between these groups of prokaryotes is greater than the genetic difference between the four eukaryotic kingdoms.

What are the three domains in the tree of life?

Bacteria, Archaea, Eukarya

Single celled prokaryotes. One of the largest groups of organisms on Earth.

Bacteria

Single celled prokaryotes that have the ability to live in extreme environments because of their cell walls.

Archaea

A domain that contains all organisms made of eukaryotic cells. They may be single celled, colonial, or multicellular.

Eukarya

Why do some scientists believe that bacteria and archaea have no true species?

Many of these organisms transfer genes among themselves outside of typical reproduction. They do not reproduce sexually. We define species as the ability to produce offspring by the combining of a male and female. If bacteria reproduce by binary fission, they cannot by definition be considered species.

Why are protists, plants, fungi, and animals classified into the same domain but into different kingdoms?

They all have eukaryotic cells, but are classified in different kingdoms based on differences in other characteristics.

If you come across an unusual single celled organism, what parts of the cell would you study in order to classify it into one of the three domains?

The nucleus (or lack thereof) and the cell wall

Explain, using the traditional definition of species, why it is difficult to classify some bacteria and archaea at the species level.

A species can be defined as an interbreeding group of organisms that produce fertile offspring. But bacteria and archaea do not breed to produce offspring; they reproduce by binary fission. In reproduction, parents pass genetic material to their offspring. However, many bacteria and archaea can take up genetic material from their environment – a transfer of genes outside of typical reproduction that does not occur in eukaryotes.

The Archaea lineage may include the first life on Earth, which began under much different environmental conditions from those present today. What characteristics of archaea help to support this statement?

Archaea exist in extreme environments that are similar to those of early Earth.

The scientific name for humans is Homo sapiens. What genus do humans belong to?

Homo

A particular DNA sequence accumulated three mutations over 10,000 years. After how much time would you expect this sequence to have accumulated six more mutations? Explain.

20,000 years. Mutations occur at a fairly constant rate.

Are species in the same family more or less closely related than species in the same class?

Class is a more general taxon than family. Organisms in the same family are more closely related than organisms in the same class.

How many clades are represented in this cladogram? A B C D

3 one with A, B, C and D One with B, C and D And one with C and D

What represents the derived characters that were used to construct this cladogram?

A B C D

The hash marks 1,2,3 and 4.

1

2

34

Where are the nodes in this cladogram and what do they represent?

A B C D

Nodes are where the side branches intersect with the main branch. They represent the common ancestor of the species in each clade.

Mutations in ___________ have been used to study the migration routes of humans over the past 200,000 years.

mitochondrial DNA

An infectious particle made only of a strand of DNA or RNA surrounded by a protein coat.

virus

Any living organism or particle that can cause an infectious disease.

pathogen

What key characteristics do all living things share?

They reproduce, use nutrients and energy, grow and develop, respond to the environment, and have genetic material.

Why are viruses not classified as living? They cannot reproduce on their own.

They do not grow or develop.

Infectious particles that cause disease in plants and are made of single stranded RNA without a protein coat.

viroids

An infectious particle made only of proteins that can cause other proteins to fold incorrectly. They are at the boundary between living and nonliving. They contain no genetic material.

A prion

These play a role in mad cow disease. BSE – bovine spongiform encephalopathy. And Creutzfeld Jakob disease.

prions

Why is a prion even more deadly than a virus?

The body has no immune response against a protein.

Prions were not widely known to be infectious agents until the 1980’s. Give two reasons why this might be so.

They are very small, and prion diseases often incubate for many years before taking effect.

An RNA based disease spreads through pollen. Is it likely due to a virus, viroid, or prion? Explain.

Viroids, because they are made of RNA, are passed through seeds or pollen, and infect plants.

To multiply, viruses must take over the functions of the cells they infect. Why does this make it difficult to make effective antiviral drugs?

Most drugs that would interfere with viral replication would also kill the host cell.

Who, in 1892 was studying the tobacco mosaic disease and determined that the disease-causing agent was smaller than a bacteria.

Dmitri Ivanosky, he passed extracts of diseased tobacco leaves through filter pores small enough to strain out bacteria…. he found that the extracts could still pass on the disease.

Who coined the term “viruses” and when?

Martinus Beijerinck in 1898. He showed that the causing agent for the tobacco mosaic disease could pass through agar gel. After Ivanosky and Beijerinck, scientists began finding that many diseases of unknown causes could be explained by viruses.

A single viral particle is called a ________. virion

The protein shell that surrounds the genetic material of a virus is called a _______.

capsid

How does a virus identify its host? By fitting its surface proteins to receptor

molecules on the surface of the host cell.

The genetic material of viruses can be _____ or ______; single-stranded, doubled-stranded, ________, ________, or ___________.

DNA, RNA linear, circular, or segmented

Viruses that prey on bacteria. bacteriophages

What is a very common example of a T-bacteriophage commonly found in the intestines of mammals?

Escherichia coli

Describe how the structures of a bacteriophage are well-suited for their functions.

The capsid houses the nucleic acids, the tail fibers help with attachment, and the tail sheath helps with injecting the genetic material of the viruses.

What are the two basic pathways of infection for a virus?

Lytic and Lysogenic

An infection pathway in which the host cell bursts, releasing the new viral offspring into the host’s system, where each then infects another cell.

Lytic infection

A type of viral infection where the phage combines its DNA into the host cell’s DNA.

Lysogenic infection

The viral phage DNA inserted into the host cell’s DNA.

prophage

What are the main parts of a typical virus?

capsid, protein shell, genetic material

A wart is caused by a virus that may lie dormant for years before any symptoms appear. Does this resemble a lytic or lysogenic infection?

Lysogenic. It is characterized by a virus that lies dormant.

If the virus is a foreign invader, how is it possible for the proteins of its capsid to match the receptors on the host cell’s surface?

Over time, viruses that happened to have the right protein ‘keys’ would survive and pass on these traits to their offspring. Viruses without the right proteins would not be able to successfully infect the host and would probably become extinct.

What are defenses against viruses? How do viruses normally enter a host? skin, cell membranes, cell walls cuts, scrapes, mucous membranes

(mouth, nose, eyes, ears, genitalia)

What is the most familiar viral disease for humans?

The common cold. =200 known viruses cause the cold.

A rapid outbreak of an infection that affects many people.

epidemic

A substance that stimulates the body’s own immune response against invasion by microbes.

vaccine

What are two examples of viral respiratory disease that affect humans?

influenza and SARS (severe acute respiratory syndrome)

What is the most commonly known retrovirus?

HIV (Human immunodeficiency virus)

How do retroviruses work differently from other viruses?

A retrovirus contains RNA and uses the enzyme reverse transcriptase to make a DNA copy. Retro means backward. For most viruses, DNA is used to make an RNA copy of the virus in a cell.

The loss of white blood cells caused by viral affects is called __________.

AIDS Acquired Immune Deficiency Syndrome

What makes HIV difficult to treat? HIV has a very high mutation rate.

A weakened version of the virus, or parts of the virus, that will cause the body to produce a response.

vaccines

What viruses are children in America vaccinated against?

Measles, mumps, rubella, chickenpox

A viral infection that causes a rash, itchy skin, fever, fatigue, and is prevalent in children from 12 to 18 months.

chickenpox

A viral infection that causes yellow skin, fatigue, and abdominal pain.

Hepatitis A

A viral infection that causes painful swelling in the salivary glands and fever.

Mumps

Caused from an animal bite, this viral infection causes anxiety, paralysis, and a fear of water.

Rabies

This viral infection causes fever, headache, and body ache. It comes from the bite of an infected mosquito and there is no vaccine.

West Nile

If a vaccine is in short supply, why is it often recommended that older adults and children get vaccinated first?

The immune systems of older adults and children are often weaker than those of the rest of the population, so they are more likely to become infected than a healthy person who is not very young or very old.

Why might getting a flu vaccination sometimes cause you to get a mild case of the flu?

Because you may be getting a weakened strain of the live virus in order to build up your immune system.

People infected with HIV, the virus that causes the disease AIDS, can become unable to fight off infections by organisms that normally do not harm people. Why is this so?

HIV affects the immune system of an infected person, making him or her susceptible to organisms that normally are harmless.

The most widespread and abundant organisms on Earth are _____________.

Prokaryotes. They include bacteria and archaea.

How many ‘types’ of bacteria are estimated to exist?

How many prokaryotic cells are estimated to be on the Earth?

1 billion Ten to the thirtieth power.

One gram of soil may have as many as ________ bacterial cells and _______ types of bacteria.

5 billion 10,000

Prokaryotes can be grouped based on their need for ________.

oxygen

Prokaryotes that cannot live in the presence of oxygen are called _________ __________.

Obligate anaerobes

Prokaryotes that need oxygen in their environment are called _________ _________.

Obligate aerobes

Two examples of obligate aerobes that are human pathogens are _______ and _______.

Tuberculosis and leprosy

Prokaryotes that can survive whether oxygen is present in the environment or not.

Facultative aerobe

Bacteria are often associated with illness. Why is this a misconception?

Only a small number of bacteria are pathogenic.

Bacteria are often named based upon their _________.

shapes

Rod shaped bacteria are called _________. bacilli

Spiral shaped bacteria are called ___________.

Spirilla or spirochetes

Spherical bacteria are called ________. cocci

A small piece of genetic material that can replicate separately from the prokaryote’s main chromosome.

plasmid

Bacteria may be differentiated by the amount of ___________ found in the cell wall.

peptidoglycan

Gram __________ bacteria have a thin layer of peptidoglycan and stain red.

negative

Gram __________ bacteria have a thicker peptidoglycan layer and stain purple.

positive

Prokaryotes reproduce by a type of cell division called _________ _________.

Binary fission

A process of asexual reproduction where prokaryotes can exchange parts of their chromosomes through a hollow bridge of pili formed to connect two or more cells.

conjugation

During conditions unfavorable for survival, some bacteria can produce an __________ , a specialized cell with a thick, protective wall.

endospore

Why are disinfectants alone not enough to kill all types of bacteria?

Some bacteria form endospores, which can withstand exposure to disinfectants.

Prokaryotes take up foreign DNA. How is this characteristic used in genetic engineering?

Pieces of genes can be inserted into the genetic material of prokaryotes so that they will make the protein products encoded in the genes or copies of the genes themselves.

Prokaryotes multiply by binary fission, which simply divides a cell in two. Why are mutations and conjugation important for natural selection in prokaryotes?

Binary fission produces no variation, but mutations and conjugation do. Natural selection requires variation in a population.

Bacteria in your mouth convert foods containing sugar and starch into acids that can then cause cavities in your teeth. These bacteria will be present even if you brush your teeth, floss, or use mouthwash. So why are those hygiene habits so important?

These habits keep the populations down by killing them or removing the food that they convert into acids.

What are two ways in which prokaryotes that live within our bodies are helpful to us?

They provide nutrients, and they exclude pathogenic bacteria.

What kinds of foods require bacteria for their production?

Dairy products such as cheese and yogurt, soy products such as tofu and soy sauce, alcoholic beverages, and pickled foods.

What role do bacteria play in agriculture? Nitrogen fixation

A process that uses microbes and other living things to break down pollutants.

bioremediation

Provide an example in which the use of bioremediation either has improved the environment or has the potential to do so.

Cleaning up industrial accidents, sewage, and other waste.

How do prokaryotes lend stability to an ecosystem?

Prokaryotes lend stability to an ecosystem through their role as decomposers. Other organisms rely on prokaryotes for nitrogen and other compounds that are broken down through prokaryote metabolic activity. Some also release oxygen during photosynthesis.

A poison released by an organism. toxin

This common bacteria invades the lungs and kills the white blood cells that respond. The tissue releases enzymes that cause swelling which further damages the host lung tissue.

Mycobacterium tuberculosis

This bacteria normally lives in nasal passages. It is transferred to food when people do not wash their hands.

Staphylococcus aureus

Food contamination by this bacterium often comes from improper home canning or dented cans with microfractures.

Clostridium botulinum or botulism

If we regard ourselves as being under attack by viruses and bacteria, how do we fight back?

For some viruses, we have vaccines; for bacteria we have antibiotics

Who can adapt faster to the tactics of the other – humans or bacteria?

Bacteria; because bacterial lifespans are so brief, mutations accumulate much faster, allowing them to quickly adapt to the challenges we create, like antibiotics.

Chemicals that kill or slow the growth of bacteria. They work by stopping bacteria from making cell walls.

antibiotics

A common bacterium that causes an extremely sore throat.

streptococcus

Why do antibiotics not work on viral infections?

Viruses lack cell walls

Why don’t antibiotics affect our bodies’ own cells?

Antibiotics act on characteristics that are unique to bacterial cells, such as their cell walls.

How has the overuse of antibiotics caused a serious public health crises?

Resistance occurs as a result of natural selection. As individuals who are more resistant are more likely to survive and reproduce. This has led to the evolution of multidrug-resistance strains of ‘superbugs’ that are almost impossible to treat.

How can the overuse of antibiotics create ‘superbugs’?

They may create a selective pressure that favors the bacteria they are intended to destroy. Using antibiotics when bacteria are not causing an illness may make some resistant.

How can the underuse of antibiotics create ‘superbugs’?

Failure to take the entire course of antibiotics prescribed for a bacterial infection. You may not have destroyed all of the bacteria, only the weakest ones.

Pesticide resistance occurs in much the same way as antibiotic resistance. How could we apply what we have learned about antibiotic resistance to how pesticides are used in the environment?

If pesticides are used without being needed, resistance will build up so that when pesticides are needed, they will not work.

The term flagellum comes from the latin word flagnum, which means _________.

whip

The term conjugation comes from the Latin word conjugare, which means ‘to join together’. Using this meaning, explain how it relates to what conjugation is.

Conjugation is the transfer of genetic material between prokaryotes. It occurs when two or more cells join together through a conjugation bridge of pili.

The term epidemic comes from the Greek words epi and demos which mean…

Upon people

A eukaryote that is not an animal, a plant, or a fungus.

A protist

Protists can be divided informally into three broad categories based on how they get their food.

Animal like, plant like, and fungus like

What are the four kingdoms within the domain Eukarya?

Animalia, Fungi, Plantae, Protista

What is the argument for placing protists in more than one kingdom?

Techniques in molecular biology have revealed how different some groups of protists are compared to each other. They have as many differences as the fungi, plant, and animal kingdoms have compared to each other.

What observable trait might green algae and plants share that support the molecular evidence that these two groups are closely related?

Both are green, have chloroplasts, are eukaryotic, and are multicellular.

Organisms that get their food by ingesting it are called heterotrophs, while those that make their own food are called autotrophs. Categorize animal like, plant like, and fungus like protists using these two terms.

Animal like protists and funguslike protists are heterotrophs …plantlike protists are autotrophs

An informal term used to describe the many phyla of animal like protists.

protozoa

Animal like protists that have one or more flagella at some point in their life cycle.

zooflagellates

Prokaryotic flagella attach to the ________, whereas eukaryotic flagella are extensions of the ________.

Surface of the cell, cytoplasm

What role does a zooflagellate play for a termite?

Termites cannot digest wood. The zooflagellates break the wood down into digestible nutrition.

Two groups of protozoa that can easily change shape as they move are the _______ and the _______.

Amoebas, foraminifera

A temporary extension of cytoplasm and plasma membrane that helps protozoa move and feed. A false foot.

pseudopod

Describe how an amoeba eats. An amoeba eats by a process called

phagocytosis. It surrounds its food with its pseudopod, and the outer membrane then forms a food vacuole, or sac. Digestion enzymes enter the food vacuole from the surrounding cytoplasm, and digestion takes place.

A group of protozoa, with pseudopods, and form multichambered shells. They make up a large group of marine protozoa.

Foraminifera

Paramecium have __________, short, hairlike structures that cover some or all of the cell surface and help the organism swim and capture food.

cilia

What functions do the two kinds of nuclei within Paramecium perform?

The macronucleus controls cell structures and activities. Micronuclei contain all the cell’s chromosomes and function only during conjugation, a process of genetic exchange.

Protists cause some of the world’s most well known infectious diseases. The phylum __________ includes about 4000 species, all of which are parasites of animals. Most members of this phylum are known as sporozoans because they form ____________ - infectious cells that have tough outer coats. Malaria is caused by sporozoans. It is caused by infection with the protozoan __________.

Apicomplexa Sporozoites Plasmodium

How do the parasitic protists Plasmodium and Giardia infect humans?

Plasmodium is transmitted by mosquito bites, whereas Giardia is ingested through contaminated water.

Many single-celled plantlike protists are free-living aquatic organisms that, together with photosynthetic bacteria, are known as ___________.

phytoplankton

____________ provide about half of the oxygen in Earth’s atmosphere.

Phytoplankton

Several species of single-celled plantlike protists, such as __________, live in colonies.

volvox

Photosynthetic plantlike protists are called ____________.

algae

A large group of single celled organisms that swim with the aid of one or more flagella. Most are photosynthetic. Structures include contractile vacuoles, a pellicle, a nucleus, chloroplasts, an eye spot, and flagella.

Euglenoids

A flexible coat like covering on the cell surface. This feature (structure) allows the cell to change shape. In some creatures, this structure allows the organism to creep across solid surfaces.

Pellicle

A single celled protist. 90% are marine plankton. They have two flagella, one that propels it forward and another that changes its shape to turn it over or change direction. The second flagella is wrapped around the body. Some species even have a protective armor. Some are bioluminescent.

Dinoflagellates

A large population of dinoflagellates can create what is known as a ___ ______. When ocean currents bring up nutrients from far below the ocean surface a ___ ______ occurs. The higher nutrient levels produce a bloom. The toxic bloom may kill large numbers of fish and can even contaminate fish that humans eat.

Red Tide

Tiny single- celled algae that are covered with delicately patterned glass- like shells. All release oxygen into the environment.

Diatoms

These may be found in water or on land. They are multicellular and contain chlorophyll. They are probably an early ancestor to land plants because they have carotenoids, accessory pigments, cell walls, and starch.

Green Algae

Giant kelps that form thick underwater forests. Some may grow as high as 100 meters. They are photosynthetic but have chlorophyll C.

Brown Algae

Most are found in the ocean. A few in freshwater. They are filled with chlorophyll A. They get their own color from the pigment phycoerythrin . They can grow at very deep depths because the pigments allow for the absorption of blue light that reaches the deeper parts of the ocean.

Red algae

All algae can reproduce______. Asexually

If a multicellular organism contains chlorophyll C but no silica, to which phylum does it likely belong?

Phylum Phaeophyta. The brown algae.

Many biologists argue that the euglenoids should be classified as an animal- like protist rather than a plantlike protist. Explain.

Some Euglenoids lack chrorophyll and eat other organisms, while others use an animal- like creeping method of locomotion.

As decomposers, fungus- like protists play an important role in ecosystems by recycling nutrients such as _____and _____ back into the soil.

Carbon Nitrogen

Why are fungus- like protists not classified as fungus?

They can move during part of their life cycle, while fungi cannot.

Eukaryotic oraganisms that have both fungus- like and animal like traits. They can be divided into two phyla: plasmodial ___ ______ and cellular ____ _______.

Slime molds

For most of their life, these live in a single mass of cytoplasm that actually is a large single cell with many nuclei. They may grow as large as a meter. They move like a giant amoeba.

Plasmodial slime molds

The dog vomit slime mold. Fuligo Septica

Where are plasmodial slime molds typically found?

On the underside of logs and on dead leaves

When food or moisture is in short supply it will stop growing and develop reproductive structures to produce spores.

Why are cellular slime molds interesting to biologists?

Each cell in a cellular slime mold is independent but they act as a group. They are common in soil. When food is scarce, individual cells can release chemical signals that cause the cells to swarm together.

Fungus-like protists made of branching strands of cells. Common in freshwater habitats. They are decomposers but some are parasites for plants or fish.

Water Molds

What is the best known water mold? Phytophthora infestans- it caused the

potato blight in Ireland from 1845 to 1849. More than one million people died of starvation.

In what ways are slime molds and water molds similar to fungi?

These fungus like protists also are decomposers that recycle nutrients back into the soil.

Describe how slime molds help other organisms within an ecosystem obtain nutrients.

They decompose organic matter, breaking it down so that the nutrients return to the soil.

What might be the advantage of being able to switch from living as separate cells to become a coordinated unit acting like a single organism?

The different body forms can be an advantage when conditions change. When there is plenty of food, the individual cells find food easily. When food becomes scarce, they may be more likely to survive by working together to find and share food.

Fungi are amazingly diverse. Scientists have named _________ species and estimate that __________ exist.

70,000 1.5 million

Members of the kingdom Fungi fall into one of three groups- _________, __________, and the ___________.

The singled-celled yeasts, the molds, and the true fungi

What differentiates fungi plants?1) Plants have chlorophyll, fungi do not2)Fungi get food by absorbing it from their

environment.3)Plants have true roots, stems, and leaves.

Fungi do not 4) Plant cell walls are made of cellulose.

Fungal cell walls are made of chitin.(chitin is what insect exoskeletons are made from)

The bodies of multicellular fungi are made of long strands called ________.

hyphae

Hyphae often group together on long tangled masses to from a _________. It usually forms an underground network.

mycelium

A reproductive structure of a fungus that grows above ground.

fruiting body (mushrooms)

How is the way that fungi get their food different from that of any other group of organisms?

Fungi absorb their food directly from the environment, using enzymes to digest it before it enters the fungi.

The Kingdom Fungi is divided into what four main groups?

primitive fungi(phylum Chytridiomycota) sac fungi( phylum Ascomycota) bread molds(phylum Zygomycota) club fungi(phylum Basidiomycota)

The smallest and simplest group of fungi. The only fungi with flagellated spores.

Primitive, Fungi, chytrids

Yeasts, Penicillium, morels, truffles………… are all ________ _______.

sac fungi

The yeast that makes bread rise is ________ _________.

Saccharomyces cerevisiae

The mold that grows on an orange is the source for an antibiotic. The mold is _____ ______ and the antibiotic is _________.

Penicillium chrysogenum penicillin

The mold that makes the poison called aflatoxin that can contaminate cereals, nuts, and milk.

Aspergillis flavus

Mutualistic partnerships between fungi and the roots of certain plants. They help plants to fix nitrogen – they take in inorganic nitrogen from the soil and convert it to nitrates and ammonia.

Mycorrhizae

The phylum that includes mushrooms, puffballs, shelf fungi, rusts and smuts.

club fungi

Fission is identical to ______. mitosis

The reproductive features of club fungi are _____ , while bread molds are ______ , and sac fungi are _______.

basidia zygospore asci

Basidia are found on the undersides of _______. They form within the ______.

mushrooms gills

Spore forming structures at the tips of hyphae.

sporangia

Basidiomycota Club fungi

Zygomycota Bread molds

Ascomycota Sac fungi

How might producing spores benefit an organism?

Spores allow offspring to grow far from the parent organism, colonize a new area, and thereby minimize competition for space in the original location. Spores allow many more offspring to be produced.

Describe how fungi use hyphae to obtain their food.

The hyphae extend into the food source and release enzymes that break the food down. Nutrients are then absorbed across the cell walls.

The mycelium of a fungus grows underground. In what ways might this be helpful for the fungus?

It might provide protection from the environment to be underground. Even if the aboveground fruiting body is harmed, the fungus is likely to survive.

The yeast Candida is a fungus found in humans generally in the _____ and _____. Populations may grow and cause disease when the immune system is damaged.

nose mouth

Some fungal pathogens, such as _____ and ______ _____ , have fairly mild effects for humans.

ringworm athlete's foot

Why is it difficult to treat fungal infections?

They are eukaryotes with similar cell structure to ours.

Dutch elm disease is caused by a fungus that is transmitted by elm bark beetles. This disease has destroyed more than _____ of the elms in the northern U.S.

half

How can genetic engineering help peach crops from a fungus called peach scab, and Gray mold for strawberries?

Chemical sprays called fungicides help, but crops can be genetically engineered to resist fungi.

A symbiotic relationship in which both organisms benefit.

mutualism

A mutualistic relationship between a fungus and algae or photosynthetic bacteria. Only certain fungi, algae, or cyanobacteria can combine to form a ______ body.

lichen

Lichens produce hundreds of unique chemicals, including pigments used as dyes in traditional cultures and compounds that have ________ properties.

antibiotic

Mutualistic associations between plant roots and soil fungi are called ______. More than 80% of plants have _____ on their roots.

Mycorrhizae

The leafcutter ants of Central and South America don’t just use fungi, they grow them. The ants literally build a garden of leaf pieces underground. They then add pieces of fungus around the leaves. The fungus absorbs the leaf pieces and grow and the ants later eat the fungus

How are lichens useful to humans? Lichens produce oxygen They grow in unfavorable environments

which allows other organisms to grow. They are indicators of air quality. They are decomposers and return

nutrients to the soil. They can be used to produce antibiotics. Their pigments can be used as dyes.