How can we help?

You can also find more resources in our Help Center.

138 terms

Mastering Bio Unit 4

STUDY
PLAY
As a group, fungi are _____.
decomposers
Where do fungi obtain nutrients from?
nonliving organic matter
Fungi release digestive enzymes into their _____.
surroundings
What do Fungi do after they release the digestive enzymes?
absorb the digested nutrients
Basidia produce spores by a process known as _____.
meiosis
Which term describes the fusion of cytoplasm from two individuals?
Plasmogamy
What is the fusion of cytoplasm from different individuals?
Plasmogamy
Which structure is not involved in the reproduction of at least one major group of fungi?
Mycelium
A network of filaments that forms the body of a fungus
mycelium
True or false? In most fungi, fertilization is complete after the cells fuse together.
False
a two-step process consisting of the fusion of cells and then the fusion of nuclei in the fused cells
fertilization
Where does meiosis occur in a mushroom?
Basidia
specialized cells in the gills of a mushroom in which haploid nuclei fuse in preparation for meiosis
Basidia
Which structure allows the growing mushroom to nourish itself?
Mycelium
a mass of filaments with a high surface-area-to-volume ratio, which allows for efficient nutrient absorption
mycelium
Which of the following events occurs first in the development of a spore into a mature mushroom?
hyphae are produced by mitosis
What is formed after the hyphae is produced?
a filamentous network called a mycelium
True or False? Most of the cells in a mushroom contain haploid nuclei.
True
A mushroom consists mainly of hyphae that are heterokaryotic, which means they have two distinct haploid nuclei per cell; these nuclei may fuse in specialized cells called basidia and become diploid in preparation for meiosis and spore production.
Which of the following is an important role for fungi in the carbon cycle?
Fungi help release fixed carbon back to the environment for other plants and photosynthetic organisms to utilize
You decide to bake bread from scratch. Which of the following is required to make your dough rise?
Saccharomyces cerevisiae
Which of the following is NOT a reproductive structure in fungi?
Mycelia
not reproductive in nature- they are the branchlike forms that absorb nutrients and water
Mycelia
Fungi have an extremely high surface-area-to-volume ratio. What is the advantage of this to an organism that gets most of its nutrition through absorption?
The larger surface area allows for more material to be transported through the cell membrane
A cell has two haploid nuclei. This means it is _____.
dikaryotic
The Mycelia _____.
have a large surface area composed of branching hyphae
Mushrooms and puffballs are examples of structures used for _____.
reproduction
Predict what you would see if you were looking at a new species of Zygomycetes.
a zygote enclosed in a tough outer coat
You observe the gametes of a fungal species under the microscope and realize that they resemble animal sperm. To which of the following group does the fungus belong?
Chytrids
Which of these fungal features supports the phylogenetic conclusion that fungi are more closely related to animals than plants?
the cell walls of fungi are made of chitin
Karyogamy is _____.
the fusion of nuclei
What happens to the nuclei produced from karyogamy?
they undergo meiosis and become spores
Basidiomycetes are the only fungal group capable of synthesizing lignin peroxidase. What advantage does this group of fungi have over other fungi because of this capability?
This fungal group can break down the tough lignin, which cannot be harnessed for energy, to get to the more useful cellulose.
Fungi digestion _________.
is extracellular, meaning it takes place outside the organism
Which of the four major types of fungi life cycles exhibits alternation of generations?
the Chytridiomycete life cycle
Some fungal species can kill herbivores while feeding off of sugars from its plant host. What type of relationship does this fungus have with its host?
mutualistic
The fungus used to produce penicillin and other antibiotics belongs to which fungal lineage?
Ascomycota
Many amphibian populations have been decimated by a parasitic fungi belonging to which lineage?
Chytridiomycota
What impact would the spraying of fungicide have on soil-dwelling organisms?
Plant and animal diversity would decrease due to reduced amounts of available carbon and nitrogen.
Many fungi are important ________ in the soil.
decomposers
What life cycle step allows fungi to reproduce sexually without gametes?
fusion of hyphae
What does the fusion of different mating types play a similar role to?
the production of gametes
Based on the idea that fungi have pores between their cell walls, which allow cytoplasm to move from one end of the mycelium to the other, which of the following hypotheses is the most plausible?
If a single mycorrhizal fungus formed symbiotic associations with more than one tree, carbon could travel from one plant to another.
The cells of _____ and _____ have modified mitochondria.
trichomonads ... diplomonads
What cells lack mitochondria?
trichomonads ... diplomonads
The members of _____ are characterized by cells with small membrane-bounded cavities under their cell membranes.
Alveolata
What group are dinoflagellates, apicomplexans and ciliates are classified in?
Alveolata
Golden algae, brown algae, red algae, chlorophytes, and charophyceans are some examples of protists that are _____.
photosynthetic
Which of these groups consist of parasitic flagellated cells, such as Trypanosoma, the organism that causes sleeping sickness?
kinetoplastids
What are classified as kinetoplastids?
Parasitic flagellated cells
Which three groups contain large algae known as seaweeds?
brown algae, red algae, and green algae
Stramenopiles include all of the following groups EXCEPT ______.
cellular slime molds
What group do cellular slime molds belong to?
amoebozoans
Which of these groups is characterized by glasslike walls containing silica?
diatoms
Plasmodium, the parasitic organism that causes malaria, is a _____.
apicomplexan
A paramecium is a(n) _____.
ciliate
What makes use of its cilia to move and feed?
a paramecium
The largest seaweeds are _____.
brown algae
All of the organisms classified as _____ move and feed using cilia.
ciliates
Which group is characterized by cells with fine hairlike projections on their flagella?
Stramenopila
Which of these algal groups possess a photosynthetic pigment that allows them to live in deep water?
red algae
What allows them to absorb the wavelengths of light that penetrate deep water and to use them in photosynthesis?
the phycobilins and other accessory pigments of red algae
Which of these groups includes both aquatic decomposers and the parasites responsible for the powdery mildew of grapes and late potato blight?
water molds
Which algal group has chloroplasts much like those of green plants in structure and pigment makeup?
chlorophytes
What, like green plants, contains both chlorophylls a and b?
chlorophytes
Which statement is correct?
A. Unikont and bikonta lineages split soon after the origin of eukaryotes.
B. DNA sequence data have not provided useful information about protists.
C. The bikonta lineage includes animals and fungi.
D.The Amoebozoa and Alveolata form a monophyletic group
Unikont and bikonta lineages split soon after the origin of eukaryotes.
Which feature did the first eukaryotes probably lack?
cell wall
Which disease is caused by a protist?
malaria
Which of the following characteristics is true of all protists?
contain a nucleus
Plankton is comprised of photosynthetic protists and bacteria. What is the primary importance of plankton to humans?
they are food for many marine organisms that humans eat
Which of the following is most likely to lead to PSP (paralytic shellfish poisoning)?
dinoflagellates
Brown algae (protists) include unicellular and multicellular organisms. Red algae (protists) include unicellular and multicellular organisms. Amoebae (protists) include unicellular and multicellular organisms. Which of the following conclusions is consistent with the data presented?
Multicellularity evolved multiple times as eukaryotes diversified.
A particular species of protist lacks the ability to engulf food and does not contain chloroplasts. However, gene sequencing data indicate that this species evolved from a lineage containing many species with the ability to engulf food. What does this information suggest about this species of protist?
it is likely parasitic
A particular species of protist has obtained a chloroplast via secondary endosymbiosis. How can you tell?
the chloroplasts have 3 or 4 membranes
Which of the following protist lineages is appropriately paired with its supportive and/or protective structure?
Parabasalids have an internal support rod, made of cross-linked microtubules, that runs the length of the cell.
Which of the following groups is matched with an incorrect anatomical feature?
oomycota → apical complex
Where is the apical complex is found?
in the apicomplexa
In examining a multicellular protist, you notice that it uses pseudopods to engulf its food, that it reproduces asexually by mitosis, and that it has multiple nuclei. These data allow you to infer that the species belongs to which of the following protist groups?
Foraminifera
You discover a new species of protist. Which of the following characteristics would provide the strongest evidence for your hypothesis that your species belongs in Euglenida?
It contains the carbohydrate paramylon
Which group was not described in Woese's tree of life analysis?
prokarya
What characteristics were used to classify organisms before Woese's tree of life analysis?
presence of a membrane bound nucleus
Before the tree of life analysis, how were organisms classified if they lacked a membrane-bound nucleus or eukaryotes if they possessed a membrane-bound nucleus?
classified as prokaryotes
True or false? Data showing that the Bacteria were the first lineage to diverge from the common ancestor of all living organisms suggest that the Archaea and Eukarya are more closely related to each other than they are to the Bacteria.
True
What might have the common characteristics of a paraphyletic group may have arisen from?
lateral gene transfer to some, but not all, lineages.
Which of the following statements about phylogenetic trees is true?
A paraphyletic group consists of a common ancestor and some of its descendants.
Which molecule did Carl Woese study to produce his tree of life?
Ribosomal RNA
What was the molecule used to produce Woese's phylogeny because it evolves slowly and is critical to the function of the ribosome, which serves the same function in all three domains in the tree of life?
Ribosomal RNA
What is lateral gene transfer?
Physical transfer of a gene from a species in one lineage to a species in another lineage.
Lateral gene transfer is the physical transfer of a gene between distantly related lineages.
What is the best evidence that all life evolved from prokaryotic rather than eukaryotic ancestors?
The oldest fossil form of life known is prokaryotic.
What organisms are most numerous on Earth?
Prokaryotes
What two groups does the term prokaryote includes?
both bacteria and archaea,
What do Bacteria have in common with Archaea but not with Eukarya?
absence of nucleus
While examining a rock surface, you have discovered an interesting new organism. Which of the following criteria will allow you to classify the organism as belonging to Bacteria but not Archaea or Eukarya?
Cell walls are made primarily of peptidoglycan
Which of the following groups of organisms would you expect to be most abundant on Earth?
Bacteria
Virulence is defined as the _____.
ability to cause disease
Which of the following would NOT be considered an extremophile?
cells that grow very rapidly
Bacteria and Archaea are most easily distinguished from each other by their _____.
transcription and translation mechanism
Which of the following extremophiles might researchers most likely use as a model for the earliest organisms on Earth?
an anaerobic archaean species
Direct sequencing can distinguish different species of bacteria by _____.
distinguishing between different sequences of DNA nucleotides
What is a critical modern tool in distinguishing species?
DNA sequencing
Researchers have found a new type of bacteria, and they want to determine its phylum. What would be the most reliable method to do so?
Determine the ribosomal RNA sequence of the bacteria.
Methanotrophs are so named because they _____.
consume methane gas (Methano- refers to methane and -troph refers to feeding)
Organisms that synthesize their own food from simple starting materials are named _____, whereas those that absorb ready-to-use compounds are _____.
autotrophs; heterotrophs
a technique for classifying bacteria based on differences in the structure of their cell walls
gram staining
both have a plasma membrane surrounded by a cell wall that contains peptidoglycan
gram-negative bacteria and gram-positive bacteria
Does gram-positive bacteria have a thick or think layer of peptidoglycan?
thick
What color do gram-negative bacteria appear to be?
red or pink because the alcohol rinse washes away the crystal violet die
What color do gram-negative bacteria appear to be?
Purple
What are two nutritional modes of bacteria?
autotrophs and hetertrophs
-nutritional mode of bacteria that requires energy only form inorganic sources
-"self-feeders"
autotrophs
-nutritional mode of bacteria that requires energy from at least one organic nutrient
-"other-feeders"
heterotrophs
requires energy only from inorganic sources and uses chemicals as energy source
chemoautotrophs
require energy only from inorganic sources and uses light as energy source
photoautotrophs
require energy from at least one organic nutrient and uses light as an energy source
photoheterotrophs
require energy from at least one organic nutrient and uses chemicals as energy source
chemoheterotrophs
what are chemoautotrophs and chemoheterotrophs also classified as?
chemotrophs
What are photoheterotrophs and photoautotrophs also classified as?
phototrophs
-a genus of rod-shaped bacteria which appears pink after gram staining
-converts atmospheric nitrogen to ammonia
-have a thin layer of peptidoglycan
-use oxygen from cellular respiration
Azotobacter
The Gram stain is commonly used to classify a bacterial isolate into one of two groups, based on the characteristics of which of the following structures?
cell wall
Microbiologists use the Gram stain to aid in the identification of bacteria. What is the major difference between Gram-positive and Gram-negative bacteria?
presence or absence of outer plasma membrane
What experiment can distinguish between high-GC Gram-positive bacteria and low-GC Gram-positive bacteria?
DNA analysis
If Bacteria and Archaea in a 1-square-meter plot of soil were killed, what would happen?
most of the plants on the plot would die
What do nearly all plants depend on in the soil?
the nitrogen fixation of Bacteria and Archaea
Bacteria and Archaea are essential for cycling _____.
nitrogen
The prokaryotic cells that built stromatolites are classified as _____.
cyanobacteria
The prokaryotic cells that built stromatolites are classified as _____.
cyanobacteria
Are aerobic photosynthesizers
cyanobacteria
Streptococcus aureus is classified with _____.
gram-positive bacteria
What does the S. aureus attract?
the violet Gram stain
Organisms that can cause nongonococcal urethritis are classified with _____.
chlamydias
The chemoheterotroph Proteus vulgaris is a rod-shaped bacterium classified with _____.
proteobacteria
Spiral-shaped bacteria are likely to be placed with _____.
spirochetes
According to this phylogenetic tree, which of these pairs of prokaryotic subgroups share the most recent common ancestor?
Euryarchaeota.....Crenarchaeota
You have found a new prokaryote. What line of evidence would support your hypothesis that the organism is a cyanobacterium?
It is able to form colonies and produce oxygen
What is the characteristic feature of the Chlamydiales phylum?
parasitic life cycle
Which of the following groups is characterized by unusual flagella contained within a structure called the outer sheath?
Spirochaeles
While examining soil from a cornfield, you found a new type of bacteria that turns purple when treated with Gram stain. What lineage might it belong to?
Firmicutes
Which of the following lineages do not contain bacteria that are photosynthetic?
Spirochaeles
You run an osteology lab, where students are able to study the bone structure of various species. To produce clean bones, you introduce insects and bacteria to remove all remaining flesh. Which bacteria would be the best purchase for your lab?
Actinobacteria