Key Discoveries That Sparked the Genetic Revolution

1
Key Discoveries That Sparked the Genetic
Revolution

• Core 218, Spring 2007
• Biotechnology and Society

2
What you need to know about food fermentations

• If you were in a third world country, what can
  you do to perishable food?
• What is fermentation?
• What groups of microorganisms are used in
  fermentations?
• What roles do microorganisms play in fermentation?

3
Review from the Darwin Lecture

• What are the three lines of evidence that support
  to Darwins theory?
• Evidence of diversity and a demonstration of
  variation in similar things.
• Ordered and classified arrangement of life.
• Detailed anatomical knowledge.
• Who were the three most important individuals
  that contributed to the synthesis of Darwins
  theory?
• Compare and contrast the Lamarkian and Darwinian
  models for species evolution.

4
Landmark Discoveries

• Key findings that lead to the understanding of
  life and formed a basis for modern genetics.
• Separated in periods of time.
• Greek Philosophers.
• Renaissance.
• Naturalists.
• Molecular biology.
• Analytical genetics.

5
Anaximander, c.611-c.547 B.C. From
http//radicalacademy.com/gallery1.htm
6
Anaximander
Life originated from the moisture that covered
the earth before it was dried up by the sun. The
first animals were a kind of fish, with a thorny
skin. Originally, men were generated from
fishes and were fed in the manner of a viviparous
shark.
7
Other Philosophers

• Democritus (460-370 B. C.)
• If you have nothing, nothing may be created out
  of it. (Atomos).
• Aristotle (384-322 B.C.)
• "It is evident that there must be something or
  other really existing, corresponding to what we
  call by the name of Nature. For a given germ does
  not give rise to any random living being, nor
  spring from any chance one, but each germ springs
  from a definite parent and gives rise to a
  predictable progeny. And thus it is the germ that
  is the ruling influence and fabricator of the
  offspring."

8
The Dark Ages
The Dark Ages (or Middle Ages), occurred between
500 1300 AD. It was marked by illiteracy and
educational deficiencies of the commoner, few
save for the clergy knew how to read and write.
There were numerous raids by barbarians and
society retreated into kingdoms.
9
The Renaissance

• A series of cultural movements in the 14th, 15th,
  and 16th centuries that began in Italy and
  expanded into Germany, France, England and the
  rest of Europe.
• Studied the Greek civilizations and came to the
  conclusion that they were just as good.

10
Renaissance

• Renaissance thinkers believed in humanism
• Emphasizes the worth of the individual.
• People are rational beings who possess within
  themselves the capacity for truth and goodness
• It is possible to improve human society through
  classical education from ancient texts.

11
Inventions of the Renaissance

• Invention of the first compound microscope
• Zacharias Jansen, (and maybe father Hans), 1595,
  Middleburg, Holland
• The cell theory would not have been possible
  without microscopes

http//www.micro.magnet.fsu.edu/primer/museum/jans
sen.html
12
Antony van Leeuwenhoek (1632-1723)

• Father of Microscopy
• A tradesman from Holland
• Discovered bacteria, free-living protists, sperm
  cells, blood cells, nematodes, etc.
• Draper by trade, became and expert lens grinder
• Became fascinated with Hooke book
• Made over 500 simple microscopes
• Acute eyesight and lens grinding skill let him
  build microscopes that were capable of 200X
  magnification

13
Robert Hooke (1635-1703)

• Father of English Microscopy
• Experimental scientist that contributed findings
  to diverse sciences
• Universal joint
• Iris diaphram
• Respirator
• Meteorological instruments
• Keen observer
• Designed microscopes

From http//www.ucmp.berkeley.edu/history/hooke.
html
14
Robert Hooke

• Known for his highly detailed drawings

Micrographia, 1665 Cork Cells
Hookes drawing of a flea from
http//www.rod.beavon.clara.net/micro1.htm
From the Museum of Natural History
websitehttp//www.natmedmuse.afip.org/explore/mi
cro/hooke.html
15
Naturalists of the 1700s

• Naturalists were scientists that
• Studied and described living things (biology,
  zoology).
• Studies how living thing relate to one another.
• Keen observers.

16
Jean-Baptiste de Lamarck (1744-1829)
Although he is best known for his work with
animal classification and evolution, he did say,
"Every step which Nature takes when making her
direct creations consists in organizing into
cellular tissue the minute masses of viscous or
mucous substances that she finds at her disposal
under favorable circumstances."
17
Cell Theory is Formed

• 1838 Matthias Schleiden all plant tissues
  consisted of cells
• 1839 Theodore Schwann all animal tissues
  consisted of cells
• Each conjectured that there was a nucleus
• 1858 Rudolf Virchow combined the two ideas and
  added that all cells come from pre-existing
  cells, formulating the Cell Theory

18
Cell Theory

• All living things are composed of one or more
  cells.
• The chemical reactions of living cells take place
  within cells.
• All cells originate from pre-existing cells.
• Cells contain hereditary information, which is
  passed from one generation to another.

19
Cell Theory, Rudolf Virchow, 1821-1902

• All living things are composed of one or more
  cells
• The chemical reactions of living cells take place
  within cells
• All cells originate from pre-existing cells
• Cells contain hereditary information, which is
  passed from one generation to another
• Implication(s)?

20
Implications of the Cell Theory

• The information in living cells today can be
  traced back to a common ancestor
• Basis for determining relatedness

From The Online Biology Book. http//gened.emc.m
aricopa.edu/bio/bio181/BIOBK/BioBookTOC.html
21
Gregor Mendel (1822-1884)

• 1847 - Self taught scientist while serving as a
  priest in the Augustinian monastery in what is
  now known as Brno, Czech Republic
• 1850 - Failed certification as a teacher, biology
  and geology were his worst subjects
• 1851-1853 - Studied physics, chemistry,
  mathematics zoology and biology at the University
  of Vienna
• 1856 Pea experiments

22
Mendels Peas

• Traits studied seed shape, pea color, seed coat
  color, ripe pod form, unripe pod color, flower
  position, stem length
• Method cross-pollinated plants (parents),
  collected seeds (hybrids, F1 generation),
  self-crossed F1s, collected seeds and observed
  the second generation F2 phenotype
• Observed a 31 ratio

23
Homozygous dominant (SS) and recessive
(ss) Heterozygous dominant (Ss) Homozygous
dominant (SS) Heterozygous dominant
(Ss) Homozygous recessive (ss)
From www.accessexcellence.org
24
Mendel

• Mendel made his discovery before Darwin but was
  largely ignored
• Some believe Mendel never reported all his
  observations that would have prevented him from
  developing his theory of inheritance
• Implications of dominant and recessive genes?

25
Unifying Themes in Biology

• Living organisms are composed of the same
  chemical and physical components as nonliving
  things, and all life processes obey the laws of
  chemistry and physics.
• All living organisms must take in energy and
  materials to maintain their internal organization.

26
Unifying Themes in Biology

• The cell represents the lowest level of structure
  capable of performing all the functions of life.
• The organization and function of biological
  systems at many levels are maintained by feedback
  control - mechanisms that maintain the constancy
  and control the activity of the system.

27
Unifying Themes in Biology

• At all levels from the molecular to the
  macroscopic, biological structure is closely
  related to function.
• Living organisms are extremely diverse, but
  possess an underlying unity.

28
Unifying Themes in Biology

• All cellular organisms are capable of
  self-reproduction based on a set of instructions
  known as the genome.
• Life as it exists today is the product of
  evolution the change in the genomic composition
  of population of organisms over time.

29
Were Are We?

• Around the 1800s
• Animals were being used in agriculture.
• Had a few machines to do work for us.
• Lewis and Clark commissioned for the grand
  adventure.
• US had a little over 5 million people, of which
  nearly 2/3 lived within 50 miles of the Atlantic.
• Thomas Jefferson assumed office as the 3rd
  president of the United States in 1801.