LECTURE PRESENTATIONS For CAMPBELL BIOLOGY, NINTH EDITION Lectures by Erin Barley ...

102 Pages·2013·10.08 MB·English

by  Jerome Burg

LECTURE PRESENTATIONS
For CAMPBELL BIOLOGY, NINTH EDITION
Jane B. Reece, Lisa A. Urry, Michael L. Cain, Steven A. Wasserman, Peter V. Minorsky, Robert B. Jackson
Lectures by
Erin Barley
Kathleen Fitzpatrick
1
© 2011 Pearson Education, Inc.
1. Biologists use microscopes and the tools of
biochemistry to study cells
2. Eukaryotic cells have internal membranes that
compartmentalize their functions
3. The eukaryotic cell’s genetic instructions are housed
in the nucleus and carried out by the ribosomes
4. The endomembrane system regulates protein traffic
and performs metabolic functions in the cell
5. Mitochondria and chloroplasts change energy from
one form to another
6. The cytoskeleton is a network of fibers that organizes
structures and activities in the cell
7. Extracellular components and connections between
cells help coordinate cellular activities
2
1. All organisms are made of cells.
2. The cell is the simplest collection of matter
that can be alive. Indeed, many forms of life
exist as single-celled organisms.
3. Even when cells are arranged into higher
levels of organization, such as tissues and
organs, the cell remains the organism’s basic
unit of structure and function.
4. All cells are related by their descent from
earlier cells.
3
© 2011 Pearson Education, Inc.
Figure 6.1 How do your brain cells help you learn about biology?
4
 How can cell biologists investigate the inner
workings of a cell, usually too small to be seen by
the unaided eye?
5
© 2011 Pearson Education, Inc.
 The microscopes first used by Renaissance
scientists, as well as the microscopes you are
likely to use in the laboratory, are all light
microscopes.
 In a light microscope (LM), visible light is
passed through a specimen and then through
glass lenses.
 The lenses refract (bend) the light, so that the
image of the specimen is magnified
6
© 2011 Pearson Education, Inc.
Three important parameters of microscopy

Magnification, the ratio of an object’s image
size to its real size
Resolution, the measure of the clarity of the
image, or the minimum distance of two
distinguishable points
Contrast, visible differences in parts of the
sample
7
© 2011 Pearson Education, Inc.
 LMs can magnify effectively to about 1,000 times
the actual size of the specimen
 Improvements in light microscopy have included
new methods for enhancing contrast, such as
staining or labeling cell components to stand out
visually.
 The resolution barrier prevented cell biologists
from using standard light microscopy to study
organelles, the membrane-enclosed structures
within eukaryotic cells.
8
© 2011 Pearson Education, Inc.
10 m
Human height
Figure 6.2 The size range of cells
1 m
Length of some
nerve and

e
muscle cells y
e
0.1 m
d
Chicken egg e
d
i
a
n
U
 1 cm= 10-2 m= 0.4 inch 1 cm
 1 mm= 10-3 m
Frog egg
 1 m= 10-3 mm= 10-6 m 1 mm
 1 nm= 10-3 m= 10-9 m
y
Human egg p
100 m o
c
s
Most plant and o
r
animal cells c
i
m
10 m
Nucleus th
g
Most bacteria i
L
Mitochondrion y
1 m p
o
c
s
o
r
c
Smallest bacteria Super- i
100 nm m
Viruses resolution n
o
microscopy
r
t
Ribosomes c
e
10 nm l
E
Proteins
Lipids
1 nm
Small molecules
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Atoms
0.1 nm
Light Microscopy (LM) Electron Microscopy (EM)
Brightfield Confocal Longitudinal section Cross section
(unstained specimen) of cilium of cilium
Cilia
m

0
5
Brightfield
(stained specimen)
m
 2 m
0
5
2 m
Transmission electron
Scanning electron
Deconvolution microscopy (TEM)
microscopy (SEM)
Phase-contrast
m

0
1
Differential-interference-
contrast (Nomarski) Super-resolution
Figure 6.3 Exploring Microscopy
Fluorescence
m 10

10 m 1