Although fungi generally lack extensive cellular specialization, what feature of hyphal growth makes them so well suited as decomposers, mutualistic symbionts, and pathogens?
A large surface area
Fungi have unique life cycles. A fungi that has two parental nuclei in one cell is referred to as a ___________.
Chytrids are thought to be the ancestral group of fungi, even though they have flagella. Which of the following groups of features warrant their placement in the fungal kingdom?
cell walls made of chitin, ultrastructural similarities, absorptive nutrition
Common bread molds thrive in a warm, moist breadbox. How is it that they can survive in a harsh natural environment?
They produce zygosporangium
A mycorrhizae can best be described as a(n) _____________.
mutualistic symbiosis between a fungus and a plant root
Molecular data indicate that animals and fungi have a common ancestor (albeit very ancient). What morphological character provides us with a clue to the morphology of this common ancestor fungi and animals?
What is the correct order of nuclear/cytoplasmic events during the sexual reproductive life cycle of a zygomycete?
plasmogamy, karyogamy, meiosis
Fungi perform many important roles in the biosphere. Which of the following is not an environmental function of the kingdom Fungi?
photosynthetic carbon fixation
Absorptive nutrition means that fungi _____________________.
secrete digestive enzymes to break down their food outside of their cells and absorb the digested products
With the exception of flagellated spores for members of the Chytridiomycota, fungi are mostly non motile. What adaptive feature allows them to be such successful decomposers, pathogens, and symbionts?
the production of large numbers of easily dispersed spores in sexual and asexual modes of reproduction
You are a mycologist and have been asked to identify a fungus causing an epidemic on an important agronomic crop. The plant sample you've been given displays the fungus in its sexual state. Based on symptoms, you suspect that it is an ascomycete, but there isn't a conspicuous ascocarp and you'll have to use a microscope. What structure should you look for to verify that it is indeed an ascomycete?
an ascus with ascospores
Why is meiosis/sexual recombination not essential for the survival of an ascomycete?
It can produce asexual conidia in the haploid state.
Why might the term "mushroom" be confusing when we refer to basidiomycetes?
Some basidiomycetes produce microscopic basidiocarps that don't resemble gilled mushrooms.
You are an entrepreneurial vintner and are interested in making a batch of wine. Which phylum of fungi houses a fungus that will enable you to turn your grape juice into wine via yeast fermentation?
The phylum Basidiomycota is distinguished from the phylum Ascomycota because ________________.
ascomycetes produce their sexual spores in sacks of 4-8
Why does an ascus contain eight ascospores after meiosis (which usually results in the production of four genetically distinct daughter cells)?
The four haploid ascospores undergo an additional round of mitosis after meiosis is complete
Radially symmetrical organisms, such as sea stars (starfish), are placed in the bilateria because they _____________.
possess three distinct tissue layers during embryonic development
According to Daniel Y.-C. Wang, Sudhir Kumar and S. Blair Hedges, animals evolved _______ million years ago.
The authors of this study were able to generate this estimate by examining:
DNA mutations in nuclear genes found in members of the Kingdom Animalia
This is a mutation that has been seen in the fruit fly (Drosophila melanogaster), a protostome. What is the most likely cause of this mutant fly?
A change in the DNA sequence of a Hox gene
Evidence supporting the idea that a sponge is an animal (instead of another type of multicellular eukaryote) includes ____________________.
its ingestive form of nutrition
Evidence supporting the colonial character of sponges includes ____________.
a lack of coordination among cells in a sponge
All of the following are characteristic of the cnidarians except ___________________.
muscle tissue derived from mesoderm
Between the zygote and developing polyp stages, Obelia (the hydra whose reproductive cycle was illustrated in the tutorial) exists as a _____________.
As a consequence of being triploblastic, the bilateria are further adapted for ____________ than the radiata.
When a bilaterally symmetrical organism swims past you, the last thing you see is its _________ end.
When the snail-eating cichlid fish of Lake Malawi declined in number, scientists expected to see a(n) ______ in the incidence of schistosomiasis.
increase because when cichlids declined in number, snail populations grew and the incidence of schistosomiasis increased as well
One of the consequences of the pseudocoelomate body plan is ___________________.
a body cavity with muscle on one side only
Do a search in Google using "hookworm life cycle" then return prepared to answer the following question: With respect to picking up a hookworm infection, risky behavior would involve _____________.
walking around barefoot
Study the life cycle for cutaenous larval migrans, then return prepared to answer the following question: Humans are ____________ host for CLM, which is caused by hookworms ___________________.
not the definitive host / living in human skin
Protostomes and deuterostomes both have _________________________.
a body cavity lined with tissue derived from the mesoderm
The nautilus is a member of Class Cephalopoda because ___________________.
its head is surrounded by tentacles
This is a drawing of a clam's internal anatomy. What common mollusk feature do bivalves lack?
You encounter a terrestrial mollusk without a shell. This animal must belong to Class _____________.
Which of the following is a deuterostome character?
the coelom forms from foldings of the archenteron
Although radially symmetrical, the echinoderms are classified with the bilateria because they _____________________.
are bilaterally symmetrical during early development
Which of the following characters can be used to distinguish an echinoderm from an arthropod?
mode of embryonic development
Which of the following phyla are classified as both bilateria and deuterostome?
Echinodermata and Chordata
You discover a new extant animal species that you suspect is an arthropod. It has two major body segments and a pair of feeding appendages that look like chelicerae. This animal could be a _______.
Adult cephalochordates retain which of the following chordate characteristics?
All of the above: pharyngeal slits, a postanal tail and a notochord, a dorsal hollow nerve cord
Vertebrate features (e.g., a backbone and a closed circulatory system) are ideally suited for ________.
The fossil record indicates that the basic derived vertebrate features arose in which of the following sequences, earliest to latest?
vertebrae, jaws, legs, amniotic egg, hair
We take water for granted because we deal with it every day. What is its behavior at the molecular level? The three states, gas (steam), liquid (water) and solid (ice), obviously have very different physical properties. These properties are basically described by the two laws of thermodynamics. Based on the second law of thermodynamics (and temperature), predict the order of entropic states from lowest to highest.
ice, water, steam
A reaction with a delta G of -1.6 is __________.
exergonic, and work can be done with energy released from the reaction
Which has less energy, ten milliliters of water or ten cubic centimeters of ice? (Note: one cubic cm = one ml)
Which of the following is an example of mechanical cellular work?
The contraction of facial muscles to raise eyebrows
Many organisms (including ourselves) break down (catabolize) glucose to obtain energy to do cellular work. The overall reaction in the presence of oxygen is: glucose + oxygen --> carbon dioxide + water How much energy is released by this reaction? A two-step process is necessary to solve this problem. First, you need to know how much energy is required to break the bonds. Second, you need to compute how much energy is released. The difference is the amount of energy available to do work. In this molecule of glucose, the bonds of energetic interest are the C-C and the C-H bonds. Each C-C bond requires 76 kcal/mole to break, and each C-H bond requires about 91 kcal/mole to break. How much energy is required to break all of these bonds in glucose?
Now that you know how much energy is required to break all of the bonds in glucose, let's calculate the net energy change after the bonds reform around oxygen. (A total of 1703 kcal/mole of energy are released after all of the bonds associated with the breakdown of glucose in the presence of oxygen reform.)
686 kcal/mole, 1703 - 1017 = 686
In the previous question you calculated the amount of energy can be obtained from the complete breakdown of glucose (in the presence of oxygen). Eventually much of this energy is stored in ATP. Typically each mole of ATP can release about 7 kcals of energy. If energy were transferred from glucose to ATP with 100% efficiency (which, as you will learn, does not happen), how many ATP molecules harbor the energy contained in one molecule of glucose?
98 molecules of ATP, 686/7 = 98
NADH differs from NAD+ because it has _____________.
one more hydrogen atom (with electron) and an additional electron
The catabolism of glucose in cellular respiration involves the _______ of glucose and the ________ of NAD+.
oxidation / reduction
Substrate-level phosphorylation describes __________________________.
the direct synthesis of ATP from a phosphorylated substrate
How much energy, in calories, would be required to raise your body temperature by one degree if you weighed 50 kg (110 lbs)?
50,000 calories, 50 kg of water is equal to 50,000 grams, and it takes 1 cal to raise one gram by one degree