biology i. biology offers a framework to pose and answer questions about the natural world. what...
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Biology I
BIOLOGY: THE STUDY OF LIFE Biology offers a framework to pose and
answer questions about the natural world.
What do Biologists study?Questions about how living things workHow things interact with the environmentHow things change over time.
WHAT DO BIOLOGISTS INVESTIGATE?
Give 5 examples of investigations that affect you and the way you live.1.
2.
3.
4.
5.
CHARACTERISTICS OF LIFE
What makes an object “living”?
7 CHARACTERISTICS OF LIFE
1. ORGANIZATION AND CELLS 2. RESPONSE TO STIMULI
3. HOMEOSTASIS 4. METABOLISM
5. GROWTH & DEVELOPMENT 6. REPRODUCTION
7. CHANGE THROUGH TIME
ORGANIZATION AND CELLS
ORGANIZATION: the high degree of order within an organisms internal and external parts, and in its interactions with the living world
ORGANIZATION Cell: Smallest unit that can perform all
life’s processes
Unicellular:
Multicellular:
ORGANIZATION Complex multicellular organisms are
made up of ORGAN SYSTEMS:
Look at page 6 & 7 in your textbook.
Organs:
Tissues
RESPONSE TO STIMULI Stimulus: A physical or chemical change in
the internal or external environment.
Examples:1.
2.
3.
Why is this important?
HOMEOSTASIS Homeostasis is the maintenance of a
stable level of internal conditions even though environmental conditions are constantly changing.
Examples of homeostasis: 1.
2.
METABOLISM Living organisms use ______________ to
power all the life processes, such as repair, movement and growth.
Metabolism: The sum of the chemical reactions that take in and transform energyand materials from the environment.
GROWTH & DEVELOPMENT
What is growth?
How do living and non-living things differ in growth?
Cell Division: the formation of 2 new cells from an existing cell
GROWTH & DEVELOPMENT
Unicellular: enlargement is goal Multicellular: maturity & development
GROWTH & DEVELOPMENT Development: process by which an
organism becomes a mature adult.
Involves: cell division & cell differentiation
What types of cells are “specialized” or differentiated?
1. 2. 3.
REPRODUCTION
Do you have to reproduce to survive?
To survive, do you have to reproduce?
Reproduction: organisms producenew organisms like themselvesin this process
Page 9: look at picture
REPRODUCTION DNA :
Gene:
Deoxyribonucleic acid; containshereditary information
Short segment of DNA that containsinstructions for a single trait
REPRODUCTION Sexual:
Asexual:
Hereditary information combines from 2 organisms of the same species
Information is NOT combined;The original organism and the newOrganism are genetically the sameEx. Bacterium
CHANGE THROUGH TIME The ability of POPULATIONS to evolve….
Why is this important?
THEMESIN
BIOLOGY
Section 2
What is diversity of life?Many organisms are different,
but all living things have features in common
What is “diversity”?variety
PAGE 10 Scientists have divided organisms into
3 major branches: DOMAINS
Domain Bacteria Domain Archaeabacteria archaea
Domain Eukarya protists, plants, fungi, animals
6 KINGDOMS OF LIVING THINGS
1. Kingdom Bacteria
2. Kingdom Archaea
3. Kingdom Animalia 4. Kingdom Plantae 5. Kingdom Fungi 6. Kingdom Protista
INTERDEPENDENCE OFORGANISMS
ECOLOGY: branch of biology that studies organisms interacting with each other and with the environment
What has been the human effect on the world’s environment?
• ECOSYSTEM: communities of living species and their physical environments
EVOLUTION OF LIFE Individual organisms can change during
their lifetime, but their basic genetic characteristics do not change. HOWEVER, populations of living things DO change through time..
EVOLUTION: process in which the inheritedcharacteristics within populations change over generations;new species can develop
NATURAL SELECTION Organisms that have certain favorable
traits are better able to survive and reproduce successfully than organisms that lack these traits.
EXAMPLE:
ADAPTATIONS: traits that improve an individual’s ability to survive andreproduce.
Page 12 in your textbook
SECTION 3: THE STUDY OF BIOLOGY
All of science is characterized by ______________ & _______________
Scientific Method1.Observation2.Hypothesis3.Experiment4.Collect Data5.Conclusion
SCIENTIFICMETHOD
1. State a problem: the act of perceiving something that causes someone to pose a question.
2. Collect information: looking up info to forma a hypothesis
3. Hypothesis: an educated guess; If___,then___ Created from a PREDICTION: a statement that forcasts what would happen in
a test situation
4. Experiment: tests the hypothesis and it predictions
5. Analyze Data: collect all data
6. Conclusion: based on data collected
7. Repeat: share info with peers
OWL EXPERIMENT VARIABLE
INDEPENDENT DEPENDENT(responding
variable)This is affected
by the independent variable.
Presence orabsence of light
Distance from theowl’s strike to the mouse’s head
STEP 4: COLLECTING DATA
Analyzing & Comparing Data
Can create a graph such as this to show such things as distance, #’s, statistics, etc.
STEP 5: CONCLUSION In our data, what is the conclusion?
Which hypothesis is supported?
INFERENCES An inference is a conclusion made on
the basis of facts and previous knowledge rather than on direct observations.
How is an inference UNLIKE a hypothesis?It cannot be directly tested.
WHAT DO WE DO NEXT? THEORY:When many hypotheses are
confirmed to be true, it can beconsidered a theory.
Then, we must communicate our ideas!Some people publish papers, while others conduct a peer review.
MICROSCOPES AS TOOLSCompoundLightMicroscope
MAGNIFICATION AND RESOLUTION
Magnification: the increase of an objects apparent size
Eyepiece X objective= magnification
Resolution: the power to show details clearly
Physical properties of light source limit resolution (only up to 2000x)
May need more powerful scope for better resolution
STAGE SCOPE Allows for viewing of entire specimen.
Cannot get resolution, just magnification.
Perfect for viewing bugs or other WHOLE specimens.
ELECTRON MICROSCOPES
SEM TEM
Scanning ElectronMicroscope:
passes beams of electrons over a specimen to create a 3-D image of surface
creates great detail of only the surface
Transmission ElectronMicroscope:
transmits beam of electrons through a thinly sliced image
creates great resolution of internal structure