Transcript Chapter 1 The Scope of Biology

Chapters 1 &2
The Scope & Science of Biology
Enduring Understandings:
•Biology explores life from the global to the microscopic scale
•Biology explores life in its diverse forms
•Ten themes unify the study of life
• Biology: The study of
life or living and onceliving things.
• Living things share 8
characteristics.
• No single
characteristic
sufficiently describes a
living thing.
Characteristic
Description
Made of cells
Many microorganisms such as bacteria are unicellular; Plants
and animals are multicellular
Reproduce
Maple trees reproduce sexually; Hydra reproduce asexually
through budding
Based on a universal genetic
code (DNA)
Flies produce flies, dogs produce dogs, seeds from maple trees
produce maple trees
Obtain and use materials and
energy
Plants obtain their energy from the sun; Animals obtain their
energy from the food they eat
Grow and develop
Flies begin life as eggs, then become maggots, then become
adult flies.
Respond to their environment
Leaves and stems of plants grow towards light
Maintain homeostasis
Despite changes in the temperature of the environment, a robin
maintains a constant body temperature.
As a group, change over time
(evolution)
Plants that live in the desert survive because they have become
adapted to the conditions of the desert.
What are cells?
• Cells – collection of
living matter enclosed
by a barrier that
separates the cell from
its surroundings.
• Organisms consisting
of only one cell are
unicellular
(bacteria)
• Organisms consisting
of more than one cell
are multicellular
(dogs, trees, humans)
2 Types of Reproduction
Sexual reproduction:
requires two cells from
different individuals
unite to produce the
first cell of a NEW
organism.
Asexual reproduction:
a single organism can
reproduce without the
aid of another.
Growth and Development
• Most living things go through a
cycle of change called
development.
• A single cell that starts an
organism’s life divides and
changes again and again to
form the many and varied cells
of an adult organism.
• As this process continues,
organisms experience a process
called aging in which the
organism becomes
progressively less efficient and
eventually dies.
Obtaining and Using Energy
• All organisms require energy
to build the substances that
make up their cells.
• Metabolism: the total sum
of all chemical reactions in
the body.
• Anabolism: process in a
living thing that involves
putting together or
synthesizing, complex
substances from simpler
ones (Example?)
• Catabolism: process in a
living thing that involves the
breakdown of complex
substances into simpler ones
(Example?)
Catabolism
Anabolism
Catabolism
Responding to Their Environment
• Stimulus - anything in the
environment that causes an
organism to react. (Examples?)
• Irritability – the ability of living
things to respond to stimuli.
(Plant leaves, stems & roots)
• Homeostasis – an organism’s
ability to maintain constant or
stable conditions that are
necessary for life. . . Examples?
Organizational Levels of Life
Hierarchal System of Classification
Three Domains of Life
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Biological systems
Cellular Basis of Life
Form & Function
Reproduction & Inheritance
Interaction with the Environment
Energy & Life
Regulation
Adaptation & Evolution
Biology & Society
Scientific Inquiry
Biological Systems
Cellular Basis of Life
Euglena
Form & Function
Reproduction & Inheritance
Interaction with the Environment
Energy & Life
Regulation
Adaptation & Evolution
Biology & Society
Scientific Inquiry
Self-Assessment
• Use an example to describe one of the
ten themes of biology discussed.
• Identify and explain a way you have
interacted with the environment
today.
• In biological terms, are you a producer
or consumer? Explain.
Self-Assessment
• Which of the following levels of
organization includes all the others?
– Organisms, cells, biosphere, molecules, ecosystems
• Explain the relationship between the terms
species and organism
• Identify the categories of classification from
largest to smallest.
State the Problem
Form a Hypothesis
Set Up a Controlled Experiment
Record Results
Analyze Results
Draw a Conclusion
Publish Results
• A hypothesis should be tested by an experiment in which
only one variable, the independent variable, is changed
at a time.
– The set up with the I.V. introduced is the
experimental set-up.
– The control set-up does not have the I.V. introduced
and is used for comparison
• The result that you measure is called the dependent
variable
• All other variables, the controls or controlled variables,
should be kept unchanged, or controlled.
In 1668, Francisco Redi proposes an experiment to
prove
that
maggots do not arise from meat “out of
Section
1-2
nowhere.”
Controlled Variables:
jars, type of meat,
location, temperature,
time
Manipulated Variables:
gauze covering that
keeps flies away from
meat
Identify the following components of Redi’s experiment:
•Dependent variable
•Independent variable
•Controlled variables
According to the diagram, what should Redi conclude?
• A hypothesis is a prediction, or educated
guess about why or how something occurs
in nature.
• A theory is when a particular hypothesis
is supported by many scientists after
rigorous testing.