Download Chapter 1/2 PPT - Mr. Martino`s Blog

Key Chapters
Chapter 1 – Exploring Life:
Introduction to biology
Chapter 2– The Science of
Biology
College Prep Biology
Mr. Martino
1.1 Life’s Organization
Interactions occur at and across all levels of life
– Biosphere
ecosystem
community
population (species)
organism
organ systems
organs
tissues
cells
molecules
atoms
 The full spectrum of these interactions encompasses the
scope of biology (study of life)
 Organisms are highly interdependent - energy flow begins
with producers: plants and other organisms that make
their own food
 Consumers: animals that directly or indirectly rely upon
 Decomposers: break down organic material and cycle
it back to the producers
Life’s Organization con’t..
 Biosphere – all the parts of the Earth that are inhabited by
living things
– Includes land, water, air.
 Ecosystems – a community of living things in an area
which feature living and nonliving components of the
biosphere
– Biotic factors = living components
– Abiotic factors = nonliving components
 Organisms – made up of cells that contain a unique
genetic code found in DNA
 Cells – basic unit of life
 DNA – genetic code responsible for the inheritance of
genes
 Genes – units of inherited information found on
chromosomes
Life’s Organization con’t..
1.2 - Biology Explores life in
its divers forms
 Species – discrete unit in nature that entitles organisms to
reproduce with one another.
 Classification: is a means of grouping organisms
– Kingdom: the 6 broadest categories
• Archaebacteria – simple, no true nucleus – inhabit
extreme environments
• Eubacteria – simple, no true nucleus – all other forms
of modern bacteria
• Protista – includes algae and protozoa – unicellular or
multicellular; plants or animals
• Fungi – molds, yeasts and mushrooms – mostly
decomposers
• Plantae – multicellular, photosynthetic organisms
• Animalia – multicellular, heterotrophic organisms
Kingdoms con’t..
Kingdoms con’t..
1.3 Ten themes that unify the study
 Themesof life
• 1. Biological system a complex organization that
allows its components to work freely but cohesively
• 2. Cells specialized units that allow the biological system
to work efficiently
• 3. Reproduction: transmission of DNA from parent to
offspring
• 3. Growth and Development: DNA guides the
increase in size and changes that occur over a life time
• 4. Metabolism: obtain and convert energy to power all
life processes
• 5. Response: sense and react to various stimuli
• 6. Homeostasis: internal balance is maintained
regardless of environment
• 7. Evolution: changes that occur as result of repro.
Biological
Themes
con’t..
 1859
– Charles Darwin’s
book:
Origin of Species by Means of Natural
Selection explained his ideas on evolution.
 Immediate best-seller…Darwin became known as
Father of Modern Evolutionary Theory
 Explained the common threads underlying life’s
diversity
 Members of the same family are similar because of
common ancestry
Main concept is Natural Selection: the process of
nature selecting the successful traits in a species
Heritable variation must be present
Heritable characteristics are exposed to
environmental factors
Overproduction of offspring
Themes - Continued
 Theory: a comprehensive idea based upon
facts, which has been tested over and over
again
– Evolution is a theory that explains diversity
– Evolution is chronicled in the fossil record,
embryology, anatomy, and molecular biology
 Adaptations: features evolved through
natural selection - aid an organism’s survival
 Mutation: molecular change in DNA
– Original source of variations in inherited traits
2.1 Biological Inquiry – Scientific Method
 “Science” from Latin derivative meaning “to know”
 There is NO single formula or rigid sequence that
scientists use for problem solving, just key
elements
 Key elements:
– Observations/Data
– Questions
– Hypotheses
– Predictions
– Tests
– Conclusion
 Science involves critical thinking and problem
solving
 Scientific process can falsify or support hypotheses
 In biology, we pose and tests hypotheses about
nature
Scientific Method - continued
 Controlled
experiment: an
experiment in which
there are two parallel
groups….
– Control group:
“normal” conditions
• Used for comparison
– Experimental group:
has a single, unique
factor
Variable: the unique
factor within an
experiment
Scientific Method - continued
 There are two types of
variables:
– INDEPENDENT: what
the experimenter
changes
– DEPENDENT: the
change that occurs a
result of the
independent variable.
Science is
adaptable
Science is selfcorrecting
Science is a
means of gaining
and
understanding
info.
2.2 – Hypothesis-Based Science
Methods of Hypothesis-Based Science
Hypothesis-Based Science…
Forming and Testing a Hypothesis
– Observation = derived from personal experiences
– Question = a problem that needs to be answered
– Hypothesis = suggested answer to a well-defined
scientific question
– Prediction = a testable statement written using
“If…then…” logic
– Test = experimental procedure designed to test the
hypothesis