...CHAPTER 4: A TOUR OF THE CELL I. CELLS ARE THE SMALLEST UNITS OF LIFE A. The study of cells began with the microscope. • Robert Hooke was the first to describe cells in 1665. • Micrographs are photos taken with microscopes • Light microscope (LM) has magnification up to 1000x o For viewing living cells • Electron microscope (EM) has magnification up to 1,000,000x o Scanning EM (SEM) for viewing surface features o Transmission EM (TEM) for viewing internal structures [pic][pic][pic] B. Why are cells small? • A cell’s surface area-to-volume ratio limits its size • Volume increases faster than Surface Area • Larger cells do not have enough Surface Area to support their Volume • Organisms get larger by becoming multicellular [pic] C. There are two major categories of cells. [pic] D. All cells are surrounded by a plasma membrane. • Prokaryotic AND eukaryotic cells are surrounded by a plasma membrane • Eukaryotic cells also have internal membranes • All membranes act as selective barriers • All membranes are built from proteins and phospholipids • Form phospholipid bilayer when exposed to water o Hydrophilic on outside, hydrophobic on inside • Membranes are described by the fluid mosaic model o Fluid because...
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...The Scientific Method Paper The Scientific Method is a process that I have always struggled with. It is a process that assists you in organizing your information. It also is useful in the fact that you are able to keep all of your steps in order. The steps that are in the Scientific Method are Observation and Questioning, Hypothesis, Testing, Results, Explanation, and New Question. The Observation and Questioning step is very important. In this step we look at what we want to do an experiment on. In the Hypothesis step, you guesstimate what the outcome of the experiment will be. I feel that the Testing step is self-explanatory. In this step you perform your experiment and test the hypothesis you came up with in the previous step. After you perform your experiment, you have the Results step. This is where you have your outcome. If your outcome supports your hypothesis, then you are able to go onto the next step of the process. But there are times that your outcome will be different than your hypothesis, if this is the case you go back to the beginning of the process. If this happens, you have to do all of the steps all over again. Next we have the Explanation step. You need to figure out an explanation that addresses the question that you are experimenting. The final step is the New Question step. Here you come up with the conclusion to your experiment. Quite often your conclusion could lead to a whole new set of questions, in which would lead to new experiments...
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...Ronald Mathis Grand Canyon University Biology 100 July 10th 2011 The Cell Cycle Directions: Answer the following questions. Cite references as needed. Be sure to read the required Module 3 readings and view the required Web sites before completing the assignment. Cell Cycle Questions for Cell Cycle 1) . Briefly describe all phases of the cell cycle and tell what happens in each. a) Interphase: G1 phase, S phase, G2 phase Interphase: Before a cell can enter cell division, it needs to take in nutrients. All of the preparations are done during the interphase. Interphase proceeds in three stages, G1 phase, S phase, G2 phase. Cell division operates in a cycle. Therefore, interphase is preceded by previous cycle mitosis and cytokinesis (Module 3 Readings). a. G1 phase: The cell increases the supply of proteins and increases its organelles. b. S phase: Linear chromosome is replicated. c. G2 phase: Increases protein preparing to replicate. (Module 3 Readings) b) M phase: M phase is a method of indirect cell division by means of which the two daughter nuclei normally receive identical complements of the number of chromosomes of the somatic cells of the species. 2) Which phase is the shortest? Anaphase is the shortest phase of mitosis because its where the chromatids twins are all pulled apart at the centromere by the spindle fibers. 3) What is G0 (Gap 0/Resting phase)? A resting phase is when or where the cell has left the cycle...
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...Factors Affecting Student Academic Success in Gateway Courses at Northern Arizona University Russell Benford Julie Gess-Newsome Center for Science Teaching and Learning Northern Arizona University Flagstaff, AZ 86011-5697 May 24, 2006 Factors Affecting Student Academic Success in Gateway Courses at Northern Arizona University Table of Contents Section Abstract Introduction Predictors of Student Achievement in Introductory Business, Mathematics, and Science Courses Predictors of Student Achievement in Business, Marketing, and Economics Predictors of Student Achievement in Mathematics Predictors of Student Achievement in Computer Science Predictors of Student Achievement in Physics Predictors of Student Achievement in Chemistry Predictors of Student Achievement in Biology Summary of Factors That Predict Student Success in Introductory Business, Mathematics, and Science Courses Interpreting Results of Predictive Studies in Business, Mathematics, and Science Education Methods Institutional Records and Public Data ABC and DFW Rates in Gateway Courses Characterizing ABC and DFW Students Student Survey Page 4 5 10 11 13 15 18 20 21 24 27 30 31 32 34 35 1 Characterizing Students’ Educational and Socioeconomic Contexts Characterizing Gateway Classrooms and Courses Development of Predictive Model Results Course-Oriented ABC and DFW Statistics ABC and DFW Rates in Gateway Courses Teaching Styles Used in Gateway Courses Student-Oriented ABC and DFW Statistics Student...
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...| Syllabus College of Natural Science BIO/100 Version 2 Introduction to Life Science with Lab | Copyright © 2009, 2007 by University of Phoenix. All rights reserved. Course Description This course applies a broad, conceptual understanding of biology. Students are introduced to scientific ideologies and concepts that not only shape the biological world, but also shape humans. Students examine the scientific method, evolution and biodiversity, the biology of cells, physiology, the dynamics of inheritance, and the effect humans have on the environment. The text emphasizes methods and the theoretical foundations of ideas, while minimizing isolated facts. It stresses the integration of ideas, making connections that form an understanding of the living world. The weekly online labs add a practical component to the class. The labs build upon the concepts in the text and offer a chance to interact with the material and further their understanding. Policies Faculty and students/learners will be held responsible for understanding and adhering to all policies contained within the following two documents: University policies: You must be logged into the student website to view this document. Instructor policies: This document is posted in the Course Materials forum. University policies are subject to change. Be sure to read the policies at the beginning of each class. Policies may be slightly different depending on the modality in which you attend class. If you have...
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