I want to embed images into the body of my text in Word, but don't seem to have the degree of control over where it sits on the page. What is the easiest way to handle this?
Although Word will allow a user to insert an image directly into a page of a document, I find it easier to take advantage of the "drag and drop" control that is provided by first of all inserting a text box, into which the image file is subsequently inserted. Selecting the text box and dragging it into position then allows you to control exactly where on the page the image should be displayed. Right clicking on the text box frame, also shows the contextual menu that allows you to choose options for how closely the text will be displayed around the image using the "text wrapping" option.
Explain why the path of beta particles, which have a higher energy than alpha particles, is disrupted more greatly than the path of alpha particles in a cathode ray tube.
The path of beta particles traveling through a cathode ray tube will be altered significantly more than the path of alpha particles because the beta particles consist of electrons which are many thousands of times less massive than their lower energy counterparts. Alpha particles, which are essentially the nucleus of helium atoms, consist of two protons and two neutrons. Considering that an electron is 1840 times less massive than a single proton, each beta particle is 7360 times less massive than an alpha particle, causing the less massive beta particle to be more greatly affected by the electronic field of a cathode-ray tube.
The endosymbiotic hypothesis proposes that mitochondria and chloroplasts may have evolved from formerly free living bacteria having been absorbed by single celled eukaryotes. What is it about these organelles that lead to the development of this theory?
There are four main pieces of evidence that suggest the possibility of free-living bacteria evolving a symbiotic relationship with larger cells, and no longer being able to survive independently. Firstly, there is size. Both mitochondria and chloroplasts are very close in size to modern species of bacteria. Most bacteria range in size from 1-10 microns in length, the same range of sizes for mitochondria and chloroplasts. Secondly, the plasma membrane of these organelles is very similar to those of independent bacteria. Thirdly, during cellular division mitochondria are "copied" by pinching in the middle - a process identical to the reproduction of bacteria through binary fission. Lastly, and perhaps most significantly, Mitochondria and Chloroplasts contain DNA that is arranged in a ring form, indistinguishable to the plasmids (circular DNA) found in bacteria. The DNA found in eukaryotic cells is linear in structure. Because of these four pieces of evidence, it is understandable that scientists have hypothesized that modern mitochondria and chloroplasts evolved from bacteria that had been free-living. All it would take is for a larger heterotrophic cell to take in the bacterium, but for whatever reason, not digest them.