1. How does the surface area-to-volume ratio of a small cell compare to that of a large cell? (2 points) 2. What do the results of the agar blocks indicate about the relationship between cell size and time for
materials to reach the center of the cell? (2 points)
3. How does being small help cells survive? (2 points)
4. Include an explanation of how the surface area-to-volume ratio, diffusion rate, and time for substances
to reach the center are related. Support your explanation with data. (6 points)
5. How does being made of many cells help large organisms maintain homeostasis? (6 points)

Ashort, vertical, solid, or fleshy stem possessed by gladiolus and which is used in reproduction is termed a . termed a .

When is your respiration rate likely to change? a. when your intestines are digesting b. when your cells have too much glucose c. when your cells need more oxygen d. when your liver is working after a meal

Rease is an enzyme used by plants to break down urea (a nitrogen-containing compound) into carbon dioxide and ammonia. urease urea > > > carbon dioxide and ammonia ammonia is broken down by plants into a nitrogen source plants need to grow. thus, plants could not use urea as a nitrogen source unless it was first converted to ammonia. in soybean plants there are two different kinds of urease, one produced in the seeds and the other produced in the leaves of the plant. three types of soybean plants were used in a set of experiments: normal soybeans and two mutant strains, one lacking the urease in the seeds only (strain 1) and one lacking urease in the leaves only (strain 2). experiment 1 separate areas in a field were planted with normal, strain 1, and strain 2 soybeans. all types of soybeans appeared to grow, flower, and produce seeds equally well. there were no externally detectable differences among the strains. experiment 2 small pieces of plant leaves of equal weight were obtained from each type of soybean plant and separately placed on media in culture dishes. tissue growing in this way will become an unorganized clump of cells referred to as callus. to provide a controlled nitrogen source, half the tissue samples of each type were placed on media containing urea, and the other half of the samples were placed on media containing ammonia. after 30 days, the weight gain for each of the callus samples was determined. results are shown in the table below.