University:
Missouri State University
Course:
BIO 121 | General Biology I
Academic year:

2021
Views:

440

Pages:

33
Author:

Drevzh

Cell Theory INTRODUCTION Objectives: Identify the parts of the cell theory and scientist contributions. DO NOW: WHICH ITEMS CONTAIN CELLS AND WHICH DO NOT? EXPLAIN YOUR ANSWER. ROCKS GRASS SOIL TELEPHONE POLE GRASSHOPPER WATER HOMEWORK: CREATIVE WRITING Cellular Organization Cells → Tissues → The smallest Made up of unit of life: many of the Skin Cell same cells: Skin Tissue Organs → Made up of many different tissues: Stomach Organ Systems Made up of many different organs: Digestive System IMPORTANT EVENTS IN THE DISCOVERY OF THE CELL AND THE DEVELOPMENT OF THE CELL THEORY….. http://learn.genetics.utah.edu/conte nt/begin/cells/scale/ 1665 – Robert Hooke  Observed cells in cork  Coined the term “cells” Cork Cells 1673 – Anton van Leeuwenhoek  Observed pond water  Created a powerful microscope 1827-33 – Robert Brown  Noticed that pollen grains in water jiggled around  Called “Brownian motion” • Discovered the nucleus Nucleus Human Cheek Cell 1838 – Matthias Schleiden  A botanist who concluded that all plants are made of cells. Typical Plant Cell 1839 – Theodor Schwann A zoologist who concluded that all animals are made of cells. Nerve Cells 1855 – Rudolf Virchow  A physician who did research on cancer cells and concluded: “Ominis cellula e cellula”  “All cells are from other pre-existing cells.” The Cell Theory 1. All living things are made of one or more cells. 2. Cells are the basic units of structure and function in organisms. 3. All cells arise from pre-existing cells. Cells are diverse… In size, shape, and internal organization. Creative Writing:  Write either a Poem, Song or Children’s Story  Include the scientists who helped develop the cell     theory Include how the theory was developed Include the three statements of the Cell Theory Create a Title and Submit neatly written on lined paper Appropriate illustrations always welcome Ted Ed: Wacky Cell Theory Cell Size  Must remain small in size  SA:V  Surface Area - total area of the surface of an object  (Length x width) x sides  Volume – total space inside an object  Length x width x height SA:V So What???  As cell increases in size, surface area becomes too small to support internal structures   Oxygen and other nutrients cannot diffuse fast enough Cells will divide  Exchange of nutrients quicker over short distances!!  Cell dies if nutrients are not received fast enough  How can a round cell increase surface area but not volume??? Examples of SA:V Flowering plants have an extensive, branched rooting system to absorb water and minerals Examples of SA:V  Mammals have a long small intestine with internal folding to absorb digested food Objectives: Compare the structures of prokaryotic and eukaryotic cells. Describe the structure of cell membranes. DO NOW: CREATE A TIMELINE IN YOUR NOTES, ADD TO IT THE SCIENTISTS WE LEARNED ABOUT YESTERDAY AND ONE WORD TO DESCRIBE THEIR CONTRIBUTION HOMEWORK: FORMATION OF CELL THEORY WORKSHEET Two types of cells 1) Prokaryote  Simple cells that do not have internal membranes  Ex. bacteria 2) Eukaryote  More complex cells that do have membrane-bound internal structures  Ex. Plant and animal cells Bacterial Cell Main differences Prokaryotic Eukaryotic  Few internal structures  Membrane-bound  No nucleus  DNA not organized into chromosomes  Unicellular organisms organelles  Have a nucleus  DNA organized into chromosomes  Most living organisms Prokaryotes and Eukaryotes (all cells, really) have several structures in common: DNA Ribosomes Plasma Membrane Cytoplasm Eukaryotic Prokaryotic Prokaryotic Eukaryotic Prokaryote Both Eukaryote 1. Cells contain to evolve Have DNA Nucleus 2.Lacking and 2.Larger and Cell Nucleus Membranes more complex 3.Simple Cell 3.Highly 4.Ex: Bacteria Specialized 1.1st Cell Membrane  Plasma Membrane  Made of phospholipids and proteins  Selectively permeable Outside of cell Proteins Carbohydrate chains Cell membrane Inside of cell (cytoplasm) Protein channel Lipid bilayer What does it do?? Acts as a boundary Controls what enters/leaves cell Phospholipids HYDROPHILIC → HYDROPHOBIC → Membrane Proteins  Peripheral –stick on the surface  Inside or outside cell  Integral – stick into the membrane  Can go part way or all the way in Glycoprotein  Proteins with carbohydrates attached Transport Proteins  Helps move substances across cell membrane