Which of the following is/are true according to the Cell Theory? 1) All organisms are composed of one or more cells. 2) The cell is the structural unit of life. 3) Cells can arise only by division from a preexisting cell. 4) Cells divide only by fission.

Use this dichotomous key for insect identification to identify the insect shown. 1. a. insect has one pair of wings. order diptera b. insect has two pairs of wings. go to #2 2. a. front wings thicker in texture than hind wings go to #3. b. front and hind wings are same texture throughout. go to #4 3. a. front wings are short order dermaptera b. front wings cover entire abdomen order coleoptera 4. a. wings with scale on all parts of their area. order lepidoptera b. wings without scales go to #5. 5. a. hind wings smaller than front wings. order ephemeroptera b. front and hind wings nearly equal in size. order odonata the insect pictured is in the order diptera. ephemeroptera. coleoptera. odonata.

What are some natural processes that represent physical and chemical changes?

When ash and dust begin to settle on the ground, they eventually become compacted by