Which chordate trait evolved first?
A. Skull and backbone
B. Calcium-hardened skeleton
C. Amniotic egg
D. Four limbs
Answer: A
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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.
Photosynthetic mesophyll tissue is a type of ____
a. collenchyma b. parenchyma c. periderm d. sclerenchyma e. pericycle
Male orgasm is necessary for
a. ejaculation of semen. b. pregnancy. c. erection. d. sexual arousal. e. all of these.
The most common meaning of biodiversity is ___________.
a) the number of different ecosystems in a geographical area or on Earth b) the assortment of different chemicals produced by different organisms c) the number of species in a location or on Earth d) the amount of genetic raw material available for adaptation