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