Which of the following represents an extinct lineage of jawed fishes that are also called spiny sharks?
a. placoderms
b. ostracoderms
c. acanthodians
d. conodonts
Ans: c. acanthodians
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Ferns occupy diverse habitats and have unique adaptations. Which of the following statements regarding fern adaptations is not true?
A. Tiny aquatic ferns, such as Salvinia, float on the surface of the water. B. Epiphytic ferns, such as staghorn ferns, often produce two leaf types, one for photosynthesis and spore production and the other to form a pocket that collects organic matter. C. Azolla is a tiny aquatic fern that has been used for centuries as a biofertilizer of rice. D. Unlike many other groups of plants, ferns have not been found to have symbiotic associations with nitrogen-fixing bacteria. E. Approximately 40% of living ferns are epiphytes.
When sea turtle eggs hatch, predators gather and mortality among the hatchlings is extremely high. Once turtles reach adult size, they can live for decades. This is an example of type ____ survivorship
Fill in the blank with the appropriate word.
Which proteins form channels in the membrane that allow selected polar molecules and ions to pass through and
across the membrane?
a. transport proteins b. recognition proteins c. receptor proteins d. cell adhesion proteins e. nuclear proteins
The physical removal of microbes is called (antisepsis/degerming/disinfection).
Fill in the blank(s) with the appropriate word(s).