a two-step process consisting of the fusion of cells and then the fusion of nuclei in the fused cells
specialized cells in the gills of a mushroom in which haploid nuclei fuse in preparation for meiosis
a mass of filaments with a high surface-area-to-volume ratio, which allows for efficient nutrient absorption
Which of the following events occurs first in the development of a spore into a mature mushroom?
hyphae are produced by mitosis
True or False? Most of the cells in a mushroom contain haploid nuclei.
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?
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
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?
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
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.
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?
The fungus used to produce penicillin and other antibiotics belongs to which fungal lineage?
Many amphibian populations have been decimated by a parasitic fungi belonging to which lineage?
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.
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 members of _____ are characterized by cells with small membrane-bounded cavities under their cell membranes.
Golden algae, brown algae, red algae, chlorophytes, and charophyceans are some examples of protists that are _____.
Which of these groups consist of parasitic flagellated cells, such as Trypanosoma, the organism that causes sleeping sickness?
Which group is characterized by cells with fine hairlike projections on their flagella?
Which of these algal groups possess a photosynthetic pigment that allows them to live in deep water?
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?
Which algal group has chloroplasts much like those of green plants in structure and pigment makeup?
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.
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)?
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
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?
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
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.
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.
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?
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.
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
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
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 _____.
a technique for classifying bacteria based on differences in the structure of their cell walls
both have a plasma membrane surrounded by a cell wall that contains peptidoglycan
gram-negative bacteria and gram-positive bacteria
What color do gram-negative bacteria appear to be?
red or pink because the alcohol rinse washes away the crystal violet die
-nutritional mode of bacteria that requires energy only form inorganic sources
-nutritional mode of bacteria that requires energy from at least one organic nutrient
require energy from at least one organic nutrient and uses light as an energy source
require energy from at least one organic nutrient and uses chemicals as energy source
-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
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?
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?
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
The chemoheterotroph Proteus vulgaris is a rod-shaped bacterium classified with _____.
According to this phylogenetic tree, which of these pairs of prokaryotic subgroups share the most recent common ancestor?
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
Which of the following groups is characterized by unusual flagella contained within a structure called the outer sheath?
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?