James is making models of plant and animal cells using objects supplied by his teacher to represent organelles. for one cell, he will place the objects in a shoebox. first he fills a balloon with water and places it in the shoe box. he also drops a handful of marbles into the box. which statement most likely describes the structures he has represented so far? he is making an animal cell. the box is the cell membrane, and the balloon represents the large vacuole. the marbles are the endoplasmic reticulum. he is making a plant cell. the box is the cell wall, and the balloon represents the large vacuole. the marbles are the tiny ribosomes. he is making a plant cell. the box is the cell wall, and the balloon represents the nucleus. the marbles are the centrioles. he could be making either a plant or animal cell. the box is the cell wall, and the balloon represents the large vacuole. the marbles are the centrioles.

The gene that causes sickle-cell disease is present in a higher percentage of residents of sub-saharan africa than among those of african descent living in the united states. even though this gene causes sickle-cell disease, it also provides some protection from malaria, a serious disease that is widespread in sub-saharan africa but absent in the united states. discuss an evolutionary process that could account for the different percentages of the sickle-cell gene among residents of the two regions.

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

Which of the following statements most accurately describes convergent evolution? the process in which two similar species evolve separately from each other and share similar characteristics the process in which a single species evolves into two or more new species the process in which two entirely different species evolve in response to each other the process in which two different species evolve separately from each other but still share similar characteristics