Human Biology
Sylvia S. Mader
Michael Windelspecht
Chapter 1
Exploring Life
and Science
Lecture Outline
Part 1
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Exploring Life and Science
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Points to ponder
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What is biology?
What characterizes life?
How do we classify life?
Where do humans fit into the big picture?
How do we study science?
Where is scientific information published and
what should you be aware of?
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1.1 The Characteristics of Life
What characteristics are shared
by living organisms?
• Organized from the atom to the ___________
• Use materials and energy from the environment
• Maintain a relatively constant internal
environment (____________) That word is really important!!!!!!!!!
• Respond to internal and external stimuli
• Reproduce and _____
• Have an evolutionary history through which
organisms _______ over time
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1.1 The Characteristics of Life
How are living things organized?
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Biosphere
Regions of the Earth’s crust,
waters, and atmosphere inhabited
by living things
Ecosystem
A community plus the physical environment
Community
Interacting populations in a particular area
Population
Organisms of the same species
in a particular area
Organism
An individual; complex individuals
contain organ systems
nervous system
shoot system
Organ System
Composed of several organs
working together
brain
leaf
Organ
Composed of tissues functioning
together for a specific task
nervous tissue
photosynthetic tissue
Tissue
A group of cells with a common
structure and function
neuron
plant cell
Cell
The structural and functional
unit of all living things
Molecule
Union of two or more atoms
of the same or different elements
Figure 1.2 Levels of
biological organization.
Atom
Smallest unit of an element composed of
electrons, protons, and neutrons
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1.2 Humans Are Related to Other Animals
How do we classify humans?
Domain
Kingdom
Phylum
Class
Order
Family
Genus
Species
Human
Eukarya
Animalia
Chordata
Mammalia
Primates
Hominidae
______
______
House cat
Eukarya
Animalia
Chordata
Mammalia
Carnivora
Felidae
Felis
domesticus
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1.2 Humans Are Related to Other Animals
What distinguishes humans?
• Cultural heritage or patterns of our behavior
passed from one generation to the next
• Highly developed brains
• Completely _______stance
• Creative __________ skills
• Varied tool use
• Modification of our environment for our own
purpose which may threaten the biosphere
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1.3 Science as a Process
What do we know about science?
• Science is a way of knowing about the natural
world.
• Science and scientists should be ________.
• Scientific conclusions may change or be
modified as our _______________ and
technology increase.
• Science is studied using the _______________.
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1.3 Science as a Process
Scientific theories in biology
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1.3 Science as a Process
The steps of the scientific method
Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display.
Observation
New observations
are made, and previous
data are studied.
Hypothesis
Input from various sources
is used to formulate a
testable statement.
Experiment/Observations
The hypothesis is
tested by experiment
or further observations.
Conclusion
The results are analyzed,
and the hypothesis is
supported or rejected.
Scientific Theory
Figure 1.8 The scientific method.
Many experiments and
observations support a
theory.
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1.3 Science as a Process
How the cause of ulcers was discovered:
The scientific method in action
• Observations: Many patients had a particular
bacterium near their ulcers.
• ___________: Helicobacter pylori is the cause
of gastritis and ulcers.
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1.3 Science as a Process
How the cause of ulcers was discovered:
The scientific method in action
• ______________________:
1st – H. pylori was isolated and grown from ulcer
patients.
2nd – Humans swallowing a H. pylori solution
developed inflammation in their stomachs.
• ____________: H. pylori was the cause of most
ulcers and can be cured by antibiotics.
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1.3 Science as a Process
A controlled study
• ___________
• Experimental variable is the variable that is
purposely changed or manipulated.
• All other variables need to remain constant.
• Groups
• Test group is a group of subjects that are
exposed to the ___________________.
• ______________ is a group for comparison that
is not exposed to the experimental variable.
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