Download File - Dr. Wall`s Science

Biology: Bio=life -ology=study of
THE PROCESS OF SCIENCE
© 2012 Pearson Education, Inc.
 The
word science is derived from a Latin
verb meaning “to know.” Science is a way
of knowing.
 Scientists
• use inductive reasoning to draw general
conclusions from many observations and
• deductive reasoning to come up with ways to
test a hypothesis
© 2012 Pearson Education, Inc.
 We
solve everyday problems by using
hypotheses.
• A common example would be the reasoning we
use to answer the question, “Why doesn’t a
flashlight work?”
• Using deductive reasoning we realize that the
problem is either (1) the bulb or (2) the batteries.
• Further, a hypothesis must be
 testable and
 falsifiable.
• In this example, two hypotheses are tested.
© 2012 Pearson Education, Inc.
Observation
Question
Hypothesis 1:
Dead batteries
Hypothesis 2:
Burned-out bulb
Prediction:
Replacing batteries
will fix problem.
Prediction:
Replacing bulb
will fix problem.
Experiment:
Experiment:
Test prediction by
replacing batteries.
Test prediction by
replacing bulb.
Test falsifies
hypothesis. Revise
hypothesis or
pose new one.
Test does not
falsify hypothesis.
Make additional
predictions and
test them.
 Scientists
began with a set of observations
and generalizations that
• poisonous animals are brightly colored and
• imposters resemble poisonous species but are
actually harmless.
Hypothesis: ??????
© 2012 Pearson Education, Inc.
 The
scientists conducted a controlled
experiment, comparing
• One control group (what are you comparing your
results to) and an experimental group
• The groups differed only by one factor
© 2012 Pearson Education, Inc.
Percent of total attacks
on artificial snakes
100
84%
83%
Artificial
king snakes
80
Artificial
brown snakes
60
40
20
17%
16%
0
Coral snakes
absent
Coral snakes
present
 Order
 Reproduction
 Growth
and development
 Energy processing
 Response to the environment
 Regulation
 Evolutionary adaptations
All forms of life share these common properties in
order to separate living from non-living
 As
we progress through the levels of
biological hierarchy, new properties
emerge at each level
• Emergent properties
In the living world, the whole is indeed
more than the sum of its parts.


Biosphere- all environments on Earth that support life
Ecosystem- all organisms living in a particular area
• Abiotic and biotic factors









Community- entire array of organisms living in a particular
ecosystem
Population- all individuals of a species living in a specific
area
Organism- an individual living thing
Organ system- organs working together for a specific
function
Organ-a structure that is composed of tissues and that
provides a specific function for the organism
Tissue-a group of similar cells that perform a specific function
CellsOrganellesMolecule-
 Cells
are the level at which the
properties of life emerge.
A
•
•
•
•
cell can
regulate its internal environment,
take in and use energy,
respond to its environment,
develop and maintain its complex organization,
and
• give rise to new cells.
 All
cells
• are enclosed by a membrane that regulates the
passage of materials between the cell and its
surroundings and
• use DNA as their genetic information.
 There
are two basic types of cells.
1. Prokaryotic cells
 were the first to evolve,
 are simpler, and
 are usually smaller than eukaryotic cells.
2. Eukaryotic cells
 contain membrane-enclosed organelles, including a
nucleus containing DNA, and
 are found in plants, animals, and fungi.
Figure 1.3
Eukaryotic cell
DNA
(no nucleus)
Prokaryotic
cell
Membrane
Organelles
Nucleus
(membraneenclosed)
DNA (throughout
nucleus)
 Systems
Biology seeks to create models
of the dynamic behavior of whole
biological systems
• Basically reducing the amount of information
down to a manageable amount to be studied
• Looks at the interactions among the parts
 All
activities of organisms are all based
on cells
• Form fits Function
Protein interaction in the cell
Outer membrane
and cell surface
CELL
Cytoplasm
Nucleus
Figure 1.10
Copyright © 2005 Pearson Education, Inc. publishing as Benjamin Cummings
 An
organism interacts with its
environment (needs order)
• Abiotic and biotic
 Energy=capacity
to do work
 Metabolism
• All the chemical reactions that occur in a cell
 The
dynamics of any ecosystem include
two major processes:
• Cycling of nutrients
• The flow of energy
Figure 1.4
Ecosystem
O2
O2
Sunlight
Heat
Producers
(such as
plants)
Consumers
(such as
animals)
Chemical energy
(food)
CO2
Water and minerals
taken up by tree roots
CO2
Cycling of
chemical nutrients
Decomposers
(in soil)
 Feedback
regulation- the output, or
product, of a process regulates that very
process
• Negative feedback
• Positive feedback
 Examples:
• Temperature regulation, plants response in a
drought
 An
accumulation of an end product slows
the process that produces that product
thus returning the changing condition
back to its set point
 Examples:
• Childbirth, ripening of a fruit, blood clotting
 The
end product speeds up the
production until it is no longer
needed…just stops
 “Amplifies” responses
 #(hashtag)Evolution-genetic
generation to generation
changes from
 Changes
through the turning on and off of
certain genes (even mutations of the genes)
• Cancer
• CF
 Diversity
in life arises from differences in
DNA sequences
 “Diversity
is a hallmark of life”
 Grouped into 3 domains
• 1.8 million species with thousands more being
added each year
• 10 million-100 million
 Taxonomy
• Branch of biology that names and classifies
species, arranges into a hierarchy
New Domains
 Bacteria
 Archaea
 Eukarya
Consists of prokaryotes
 Biological
Hieracrhy
• Domain (Bacteria, Archaea and Eukarya)
• Kingdom
• Phylum
• Class
• Order
• Family
• Genus
• Species
 In
1859, Charles Darwin published the
book On the Origin of Species by Means
of Natural Selection, which articulated two
main points.
1. A large amount of evidence supports the idea of
evolution, that species living today are
descendants of ancestral species in what
Darwin called “descent with modification.”
2. Natural selection is a mechanism for
evolution.
 Evolution
is a core theme of biology.
 Evolutionary theory is useful in
• medicine,
• agriculture,
• forensics, and
• conservation.
 Human-caused
environmental changes
are powerful selective forces that affect
the evolution of many species, including
• antibiotic-resistant bacteria,
• pesticide-resistant pests,
• endangered species, and
• increasing rates of extinction.
 Although
their goals differ, science and
technology are interdependent.
• Technological advances stem from scientific
research.
• Research benefits from new technologies.