In this exploration, you will look carefully at pictures of animals and consider some physical characteristics that scientists use to classify each organism. For each characteristic, it may be difficult to reach an accurate conclusion using only a picture. Actual classification relies on far more characteristics than are considered in this exploration, but by comparing your results, you can begin to get an idea of how each kind of organism is similar to and different from the others. Examine the pictures of the organisms in the lesson. Then fill in the Observations Table using the pictures as references. In each case, use your best judgment based on what you can see in the picture.

Observations Table

Representative organism Type of symmetry (Radial, Bilateral, or None) Type of skeleton (ENdoskeleton, EXoskeleton, or None) Type of appendages (Jointed, Not Jointed, or Absent) Segmentation (Present or Absent)
Sponges
Cnidarians
Roundworms
Annelids

Problem #3 (ch. 1, problem 15)the ideal gas law provides one way to estimate the pressure exerted by a gas on a container. the law isí‘ťí‘ť=푛푛푛푛푛푛푉푉more accurate estimates can be made with the van der waals equationí‘ťí‘ť=푛푛푛푛푛푛푉푉â’푛푛푟푟â’푞푞푛푛2푉푉2where the term nb is a correction for the volume of the molecules and the term an2/v2is a correction for molecular attractions. the values of a and b depend on the type of gas. the gas constant is r, the absolutetemperature is t, the gas volume is v, and the number of moles of gas molecules is indicated by n. if n = 1 mol of an ideal gas were confined to a volume of v = 22.41 l at a temperature of 0â°c (273.2k), it would exert a pressure of 1 atm. in these units, r = 0.0826.for chlorine gas (cl2), a = 6.49 and b = 0.0562. compare the pressure estimates given by the ideal gas law and the van der waals equation for 1 mol of cl2 in 22.41 l at 273.2 k. what is the main cause of the difference in the two pressure estimates, the molecular volume or the molecular attractions?

How many neutrons does a atom of cobalt have?

Which of the following is not a characteristic of s waves?