• Shuffle
    Toggle On
    Toggle Off
  • Alphabetize
    Toggle On
    Toggle Off
  • Front First
    Toggle On
    Toggle Off
  • Both Sides
    Toggle On
    Toggle Off
  • Read
    Toggle On
    Toggle Off

Card Range To Study



Play button


Play button




Click to flip

Use LEFT and RIGHT arrow keys to navigate between flashcards;

Use UP and DOWN arrow keys to flip the card;

H to show hint;

A reads text to speech;

26 Cards in this Set

  • Front
  • Back
What is the echinoderm endoskeleton made of?
Calcium Carbonate
What is the diagnostic trait of vertebrates?
vertebrae and a cranium
Why are the pharyngeal jaws found in many ray-finned fishes important?
they help process food
Which of the following lineages make up the living Amniota?
reptiles and mammals
What is the relationship between the dorsal hollow nerve cord and the spinal cord?
The spinal cord is a type of dorsal hollow nerve cord
Most species of hominins are known only from Africa. Which species have been found in other parts of the world as well?
H. erectus, H. neanderthalensis, and H. floresiensis
Explain how the water vascular system of echinoderms functions as a type of hydrostatic skeleton
It is an enclosed, fluid-filled structure surrounded by muscle. Muscular contraction forces water into the tube feet, resulting in extension of the podia.
Explain why each of the four key synapomorphies that distinguish chorates is important in feeding or movement. Why is it possible to say that an animal is "invertebrate chordate?
Pharyngeal gill slits function in suspension feeding. The notochord furnishes a simple endoskeleton that stiffens the body; electrial signals that coordinate movement are carried by the dorsal hollow nerve cord to the muscles in the tail, which beats back and forth to make swimming possible.
The cells that make up jaws and gill arches are derived from the same population of embryonic cells. Why does this observation support the hypothesis that jaws evolved from gill arches in fish?
If jaws are derived forms of gill arches, then the same genes and the same cells should be involved in the development of the jaw and the gill arches.
Describe genetic evidence that supports the hypothesis that the tetra limb evolved from the fins of lobe-finned fishes.
Homologous genes are involved in the formation of the fins of ray-finned fish and the limbs of tetrapods. This observation supports a prediction of the fins-to-limbs hypothesis.
The text that claims that "homo sapiens is the sole survivor of an adaptive radiation that took place over the past 7 million years" Do you agree with this statement?
The hominins fulfill the criteria for an adaptive radiation: over a short time interval, many species that occupy an array of foods and habitats evolved. Chages in tooth and jaw structure, tool use, and body size suggest that different hominin species exploited different types of food.
Explain how the evolution of the placenta and lactation in mammals improved the probability that thier offsping would survive compared to species without parental care.
Increased parental care allows offspring to be better developed, and thus have increases chances of survival, before they have to live on there own.
There is some evidence that pharyngeal gill slits occur in certain species of echinoderms that appear early in the fossil record. Explain the significance of this observation.
If confirmed, it means that pharyngeal gill slits were present in the earliest echinoderms and lost later.
When feathers first evolved, did they function in flight? Explain your logic
No - the first feathers may have functioned in display or as insulation.
The mycelial growth habit leads to a body with a high surface-area-to-volume ratio. Why is this important?
Mycelia have a large surface area for absorption
What is plasmogamy?
fusion of the cytoplasm from different individuals, without nuclear fusion
The Greek root ecto means "outer". Why are ectomycorrhizal fungi, or EMF, apty named?
Their hyphae form dense mats that envelop roots but do not penetrate the walls of cells inside the root.
The hyphae of AMF form bushy of ballon-like structures after making contact with the plasma membrane of a root cell. Why?
They increase the surface area available for the transfer of nutrients
What does it mean to say that a hypha is dikaryotic or heterokaryotic?
Two or more independent nuclei, derived from different individuals, are present.
Very few organisms besides fungi have a heterokaryotic stage in their life cycle. Which of the following is another unusual aspect of fungal life cycle?
Most varieties undergo sexual reproduction without producing eggs or sperm.
Explain why fungi that degrade dead plant materials are important to the global carbon cycle. Do you accept the text's statement that, without these fungi, "Terrestrial environments would be radically different than they are today and probably much less productive? Why or why not?
Along with a few bacteria, fungi are the only organisms that can digest wood completely. If the wood is not digested, carbon remains trapped in wood. Without fungi, CO2 would be tied up and unavalialbe for photosynthesis, and the presence of undecayed organic matter would reduce the space available for plants to grow.
Lignin and cellulose provide rigidity to the cell walls of plants. But in most fungi, chitin performs this role. Why is it logical that most fungi don't have lignin or cellulose in their cell walls?
Fungi produce enzymes that degrade cellulose and lignin
Biologists claim that EMF and AMF species are better than plants at acquiring nutrients because they have a higher surface area and because they are more effective at acquiring phosphorus (P) and/or nitrogen (N). Compare and contrast the surface area of mutualistic fungi and plant roots. Explain why fungi are particulary effefienct at acquiring P and N, compared to plants.
Plant roots have much smaller surface area than EMF or AMF. Hyphae are much smaller than the smallest portions of plant roots so can penetrate dead material more efficiently. Extracellular digestion - which plant roots cannot do - allows fungi to break large molecules into small compounds that can be absorbed.
List 3 key macromolecules found in plants that contain phosporus. Explain why plant growth might be limited by access to P.
DNA, RNA, and ATP all contain phosphorus. Without adequate amounts of phosphorus, plants cannot grow by synthesizing more DNA, RNA and ATP.
Compare and contrast the way that the fungi degrade lignin with the way that they digest cellulose
Both compounds are processed via extracellular digestion. Different enzymes are involved, however. the degradation of lignin is uncontrolled and does not yield useful products; digestion of cellulose is controlled and produces useful glucose molecules.
How is it possible for thousands of mating types to exist in a single species of fungus, instead of just two sexes like other eukaryotes?
Most fungi do not make gametes. Instead the products of specific alleles identify mating types -- probably to encourage fusion between hypae that are dissimilar genetically, resulting in the production of genetically diverse offspring. It is possible for thousands of different mating-type alleles to exist in a population.