New anatomical traits typically arise by modification of existing structures. This process constrains animal body plans and can produces structures with less than optimal function. Use an example of wings to demonstrate this point
What will be an ideal response?
The ancestors of all modern land vertebrates had a body plan with four limbs. When wings evolved in birds and bats, they did so by modification of existing forelimbs, not by new limbs sprouting. Although it might be advantageous to have both wings and arms, no living or fossil vertebrate with such a body plan has ever been discovered.
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Which of the following characteristics, structures, or processes is common to bacteria and viruses?
A) metabolism B) ribosomes C) genetic material composed of nucleic acid D) cell division E) independent existence
The Hatch-Slack cycle occurs in which of the following types of plants?
A) algae B) C3 plants C) C4 plants D) tropical grasses E) both choices C and D
Small polar and charged molecules typically cross the cell membrane by way of ____
a. simple diffusion b. osmosis c. filtration d. active transport e. facilitated diffusion
his4 TRP1; his4 trp1; HIS4 trp1; HIS4 TRP1
A haploid yeast strain has mating type a and genotype his4 TRP1. A different haploid yeast strain has mating type ? and genotype HIS4 trp1. The two strains mate and produce diploid offspring with genotype his4 TRP1 / HIS4 trp1. The diploid cells undergo meiosis to produce a variety of tetrad types. In the following questions, the genotypes of the spores in a tetrad are shown. For each tetrad, tell what type it is: parental (PD), non-parental (NPD), or tetratype (T). A) PD B) NPD C) T D) cannot be determined