Review for Lecture 1 Chapter 1 Introduction to Cells All living creatures are made of The simplest forms of life are solitary that propagate by dividing in two Higher organisms such as ourselves are like 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 in length to larger cells such as a frog s egg which has a diameter of about one Despite the diversity cells resemble each other to an astonishing degree in their chemistry For example the same 20 are used to make proteins Similarly the genetic information of all cells is stored in their Although 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 Viruses contain the same types of molecules as cells so they are considered living matter True or false 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 that change the DNA That is why daughter cells do not always match the parent cell exactly Mutations are always bad for the offspring True or false the process by which living species become gradually modified and adapted to their environment in more and more sophisticated ways offers a startling but compelling explanation of why present day cells are so similar in their fundamentals that can be understood based on the principles of mutation and selection A cell s that is the entire library of genetic information in its DNA provides a genetic program that instructs the cell how to function and for plant and animal cells how to grow into an organism with hundreds of different cell types Match the type of microscopy on the left with the corresponding description provided below There is one best match for each A B C D E F confocal transmission electron fluorescence phase contrast scanning electron bright field 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 employs a light microscope and requires that samples be fixed and stained in order to reveal cellular details 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 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 has the ability to resolve cellular components as small as 2 nm requires coating the sample with a thin layer of a heavy metal to produce threedimensional images of the surface of a sample Eukaryotic cells are bigger and more elaborate than prokaryotic cells By definition all eukaryotic cells have a usually the most prominent organelle Another organelle found in essentially all eukaryotic cells is the which generates the chemical energy for the cell In contrast the 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 which contains many long fine filaments of protein that are responsible for cell shape and structure and thereby form the cell s 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