Assignment: Mount St. Helens Succession Exploration Study the photos you found in your “Mount St. Helens succession photos” search. Scan the photograph you used here. Be sure to submit your photographs, too (i. e. scanned or digital images). Questions 1. In one part of the activity, you looked at photographs and placed them in order. How did you determine the order that the photos should go in? 2. When looking at your pictures in order, describe the changes to the area. What changes happened first? Why do you think that is? 3. The gradual change in an ecosystem in response to environmental change is called succession. From what you have learned, how is Mount St. Helens an example of succession? Explain. 4. Look at time lapse photographs of the Scorch, standing dead forest from 4 and 7 years after the blast on the site http://www. mshslc. org/return-to-life/changing-landsca pe/. By what mechanism do you think these plants arrived in the new area? How did they benefit the ecosystem? 5. Colonizing plants help prepare the soil for the growth of other species of plants Look at time lapse photographs of the Scorch, standing dead forest from 17 and 30 years after the blast on the site http://www. mshslc. org/return-to-life/changing-landsca pe/. Are these different plants than you saw in the photographs from Question 2?

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interphase

the period of cell growth when the cell synthesizes new molecules and organelles. the cell is not dividing and it constitutes the majority of the time spent in the cell cycle

prophase

changes occur in the nucleus and cytoplasm. the chromatin condenses to form structures (sister chromatids) visible with a light microscope and the mitotic spindle begins to form, but the nucleus is still in tact

prometaphase

the nuclear envelope fragments and the spindle microtubules attach to the kinetochores of the sister chromatids

metaphase

all the cell's duplicated chromosomes are lined up at an imaginary plane equidistant between the poles of the mitotic spindle

anaphase

begins when sister chromatids separate from each other and ending when a complete set of daughter chromosomes arrives at each of the two poles of the cell

telophase

the daughter nuclei form at the two poles of a cell

cytokinesis

the division of a cytoplasm to form two separate daughter cells. usually occurs during telophase during mitosis. this and mitosis make up to mitotic (m) phase of the cell cycle

answer denitrification;

the correct answers are;

a. the rock was made from more than one type of material.

e. layers of hot liquids in the rock cooled and solidified at different temperatures.

these are the two options that are related to the statement given above.