The base pairs in a dna strand are held together with hydrogen bonds. in what way would a cell be most affected if these were covalent bonds instead? a. the cell would need to make new dna every time the strand was open b. the cell would be able to open and close the dna strand when it replicated c. the cell would have to take in and use in order to brake the covalent bonds d. the would need to replace the nutritious bases each time the dna strand opened.

Interpret the model. a three-part model with black right-arrows between the parts. left part: a large green apple-shaped component with a w-shaped indentation centered on top. a small blue apple-slice shape sits above the left indentation and an arrow points from the shape to the indentation. a small purple apple-slice shape and arrow sit above the right indentation and an arrow points from the shape to the indentation. middle part: a large green apple-shaped component with a square indentation centered on top. sitting in the left side of the indentation is a blue apple-slice shape with a flat bottom, fused to a purple apple-slice shape with a flat bottom on the right side of the indentation. right part: a large green apple-shaped component with a w-shaped indentation centered on top. an up-arrow is centered above the indentation pointing to a fused blue and purple apple-slice-shaped flat-bottom component sitting above the indentation. assigne "true" or "false" to the end of each statement. the model shows a shape change occurring in the enzyme after the substrate is bound in the active site. t/fthere are two products in this model. t? f there are three substrates in this model. t/f the model shows two different enzymes. t/f

Explain the significance of thesaurus geographicus

Cladistics is a way of classifying organisms by examining the characteristics of their ancestors and descendants and depicting the relationships in a cladogram. which of the following best describes a challenge in classifying organisms this way? a. there are millions of species on earth, and a cladogram is not a practical means for classifying all of them. b. it is impossible to tell which organisms are most closely related to each other using a cladogram. c. cladograms are detail-oriented and do not provide a useful understanding of evolutionary relationships. d. there is a limited number of ways to organize the information, so most cladograms end up looking very similar.