Download Lecture Chapter 7

Cellular Structure and Function
Chapter 7
Cell
 1665
 Robert Hooke
 Microscope
 “a little room”
Cell
 The basic structural and functional unit of all living
organisms
Cell
 1838
 Matthias Schleiden
 All plants are composed of cells
Cell
 1839
 Theodor Schwann
 Animal tissue made up of cells
Cell
 1855
 Rudolph Virchow
 Cells come from cells
 Through division
Cell
 The cell theory
Cell Theory
 1. All living organisms are composed of one or more cells.
Cell Theory
 1. All living organisms are composed of one or more cells.
 2. Cells are the basic unit of structure and organization of all
living organisms.
Cell Theory
 1. All living organisms are composed of one or more cells.
 2. Cells are the basic unit of structure and organization of all
living organisms.
 3. Cells arise only from previously existing cells, with cells
passing copies of their genetic material on to their daughter
cells.
microscopes
 Compound light microscopes
 Electron microscopes
Compound
 Glass lenses
 Visible light
 10 X 10 = 100
 1000X
electron
 Magnets to aim a beam of electrons at thin slices
 500,000X
 Specimen must be dead, sliced thin and stained
Cell types
Basic Cell Types
Prokaryotic
Eukaryotic
Basic Cell Types
Prokaryotic
Eukaryotic
 No nucleus
 Nucleus
 No membrane bound
 Membrane bound
organelles
Organelles
Plasma membrane
 Special boundary
 One physical trait shared by all
Opener
 Complete the following sentence
 The plasma membrane is composed of a ______________
Quiz
 Define the following
 Osmosis
 Hypertonic
 Hypotonic
7.2
The Plasma Membrane
 Selective permeability
Plasma Membrane
Plasma Membrane
Phospholipid bilayer
Phospholipid bilayer
 Phosphate head polar to
water
 Two fatty acid tails are
repelled by water
 Fluid mosaic model
 “sea”
Other components
 Carbohydrates
 Cholesterol
 Proteins
Plasma Membrane
proteins
 Receptors – outside
 Anchors – inside
 Transport between
Opener
 The plasma membrane of a cell consists of
 A. Protein molecules arranged in two layers with polar areas
forming the outside of the membrane
 B. Two layers of lipids organized with the nonpolar tails
forming the interior of the membrane
 C. Lipid molecules positioned between two carbohydrate
layers
 D. Protein molecules with polar and nonpolar tails
Quiz
 List three cell organelles and their functions
7.3
Structures and Organelles
 Cytoplasm and
Cytoskeleton
 Cytoplasm –
 Cytoskeleton -
 semifluid material
 Network of fibers
 break down sugar
 Protein
(prokaryotic)
 provide anchor
Structures and Organelles
 Nucleus
 Ribosomes
 Nucleolus
 Endoplasmic reticulum
 Golgi apparatus
 Lysosomes
 Centrioles
 Mitochondria
Nucleus
 Directs cell functioning
 Stores DNA
Ribosomes
 RNA and protein
 Produce proteins
Nucleolus
 Site of ribosome
production
Endoplasmic reticulum
 Folded sacs
 Interconnected channels
 Protein and lipid
production
Golgi apparatus
 Flattened stack of
membranes
 Packages proteins
 Vesicles
Lysosomes
 Use Enzymes to Digest
 Excess organelles
 Worn-out organelles
 Food particles
 Bacteria
 Viruses
Centrioles
 Microtubles
 Play a part of cell division
Mitochondria
 Energy generators
 Convert fuel particles into
usable energy
 “powerhouses”
Structures and Organelles
 Vacuole
 Chloroplasts
 Thylakoid
 Cell Wall
Structures
 Cilia
 Flagella
7.4
Cellular Transport
Cellular Transport
 Diffusion
Cellular Transport
 Diffusion
Diffusion
 Dynamic equilibrium
Facilitated Transport
 Diffusion of water
 Channel protein
 Carrier protein
Osmosis: Diffusion of Water
 Water passes freely into
and out of the cell through
the plasma membrane
 In a solution, a substance
(solute) is dissolved in a
solvent
Cells in solution
 Isotonic solution
 Hypotonic solution
 Hypertonic solution
Active Transport
 Sometimes movement
from lower concentration
to higher
 Need energy
 Keeps homeostasis
Transport of large particles
 Endocytosis
 Exocytosis
Basic Cell Types
Prokaryotic
Bacteria Cells
No Membrane bound
Organelle
Eukaryotic
Animal and Plant cells
Membrane bond
organelle
Animals, plants, bacterial
What about viruses
 One or more cells
 Displays organization
 Grows and develops
 Reproduces
 Stimuli
 Energy
 Homeostasis
 Adapts over time
Cell Structure and Organelles
Plasma Membrane
 Boundary that control the
movement of substances
into and out of the cell
Cell Wall
 Inflexible barrier
 Protection and support
 Plant cell
Centrioles
 Important for cell division
Chloroplast
 Site where photosynthesis
takes place
 Double membrane
organelle
 Thylakoids
Cilia
 Aid in locomotion
 Aid in feeding
 Move things along the
surface
Cytoskeleton
 Framework for the cell
Endoplasmic reticulum
 Highly folded membrane
that is the site of protein
synthesis
Endoplasmic reticulum
 Highly folded membrane
that is the site of protein
synthesis
Flagella
 Aid in locomotion
Golgi apparatus
 Membranes
 Modifies proteins
 Packages them for
distribution outside the cell
Lysosome
 A vesicle
 Digestive enzymes
 Breakdown worn-out
material
Mitochondrion
 Powerhouse
 Makes energy available to
the rest of the cell
Mitochondrion
 Powerhouse
 Makes energy available to
the rest of the cell
Nucleus
 Control center
 Holds coded directions
 production of proteins
 cell division
Ribosome
 Site of protein synthesis
Vacuole
 Temporary storage of
materials
Protein Synthesis
Cell
Central Dogma