Transcript New Look at Living Things

New Look at Living Things
• 1600s scientists observed cells
– Most did not understand what they saw
• 1838 – cell theory
– All things are made up of tiny units of matter
called cells
– These cells divide and multiply
– They cause organisms to grow
and mature
– Developed by Mathias Schleiden
and Theodor Schwann
The Diversity of Life
• Cell theory failed to explain plants and
animal varieties
• 1800s theory of evolution was proposed
• Jean-Baptiste de Lamarck found
similarities in fossils and living organisms
• Charles Darwin built on Lamarck’s idea
– Evolution based on natural selection
Development of Genetics
• Gregor Mendel
– Experimented with pea
plants
– Trying to understand how
characteristics passed
between generations
– He discovered a gene
• Founded the study of
Genetics
Medical Advances
• Fighting Diseases
– 1796 Edward Jenner developed smallpox
vaccine
– Louis Pasteur recognized the impact of bacteria
causing disease
• Showed bacteria could be killed
• New Approaches to Surgery
– Sir James Simpson discovered chloroform
– Joseph Lister introduced methods to sterilize
instruments
Breakthroughs in Physics
• Atomic theory – all matter is made up
of atoms
– John Dalton provided proof
• Wilhelm K. Roentgen discovered X
rays
• Marie Curie and Pierre Curie
discovered radium
• Max Planck theorized that energy is
released in units called quanta
Social Sciences
• People started using scientific method to study
human behavior
– Auguste Comte believed there was a set of laws to
human behavior
– Father of sociology
• Sociology – study of human behavior in groups
• Psychology – study of human behavior in
individuals
• Ivan Pavlov – noted that human actions are
unconscious
• Sigmund Freud – father of psychoanalysis