Review for Chapter 1 Please do not memorize the answers You must understand the concepts Please do not share upload all and any lecture contents with other students who are not taking this course and at websites like Chegg and CourseHero as these sites will be monitored That is against copyright law of UNT and the book publisher so you WILL be reported and face consequences according to UNT s policies All living creatures are made of cells The simplest forms of life are solitary cells that propagate by dividing in two Higher organisms such as ourselves are like communities of cells derived by growth and division from a single founder cell Cells can be very diverse superficially they come in various sizes ranging from bacterial cells such as Lactobacillus which is a few micrometers in length to larger cells such as a frog s egg which has a diameter of about one millimeter Despite the diversity cells resemble each other to an astonishing degree in their chemistry For example the same 20 amino acids are used to make proteins Similarly the genetic information of all cells is stored in their DNA Although viruses contain the same types of molecules as cells their inability to reproduce themselves by their own efforts means that they are not considered living matter All cells are enclosed by a plasma membrane which separates the inside of the cell from its environment extraordinary ability to create copies of themselves by growing and dividing in two A cell reproduced by duplicating its DNA and then dividing in two passing a copy of the genetic instructions encoded in its DNA to each of its daughter cells That is why daughter cells resemble the parent cell However the copying is not always perfect and the instructions are occasionally corrupted by mutations that change the DNA That is why daughter cells do not always match the parent cell exactly Mistakes in the DNA sequence depending on where they occur can have positive negative or neutral effects on cell growth and survival Changes that have positive effects on survival and reproduction can lead to the enrichment called selection of cells with that change in the population Mutations are always bad for the offspring True or false Evolutions the process by which living species become gradually modified and adapted to their environment in more and more sophisticated ways evolutions offers a startling but compelling explanation of why present day cells are so similar in their fundamentals evolutions that can be understood based on the principles of mutation and selection Match the type of microscopy on the left with the corresponding description provided below There is one best match for each my expectation for microscope is understanding this type of questions You do not need to know the details for each micrsocpe A B C D E F confocal transmission electron fluorescence phase contrast scanning electron bright field D uses a light microscope with an optical component to take advantage of the different refractive indices of light passing through different regions of the cell F employs a light microscope and requires that samples be fixed and stained in order to reveal cellular details C requires the use of two sets of filters The first filter narrows the wavelength range that reaches the specimen and the second blocks out all wavelengths that pass back up to the eyepiece except for those emitted by the dye in the sample A scans the specimen with a focused laser beam to obtain a series of two dimensional optical sections which can be used to reconstruct an image of the specimen in three dimensions The laser excites a fluorescent dye molecule and the emitted light from each illuminated point is captured through a pinhole and recorded by a detector B has the ability to resolve cellular components as small as 2 nm E requires coating the sample with a thin layer of a heavy metal to produce three dimensional images of the surface of a sample Eukaryotic cells are bigger and more elaborate than prokaryotic cells By definition all eukaryotic cells have a nucleus usually the most prominent organelle Another organelle found in essentially all eukaryotic cells is the mitochondrion which generates the chemical energy for the cell In contrast the chloroplast is a type of organelle found only in the cells of plants and algae and performs photosynthesis If we were to strip away the plasma membrane from a eukaryotic cell and remove all of its membrane enclosed organelles we would be left with the cytosol which contains many long fine filaments of protein that are responsible for cell shape and structure and thereby form the cell s cytoskeleton Use the list of structures below to label the schematic drawing of an animal cell A B C D E F G plasma membrane nuclear envelope cytosol Golgi apparatus endoplasmic reticulum mitochondrion transport vesicles Circle the appropriate cell type in which the listed structure or molecule can be found Note that the structure or molecule can be found in more than one type of cell