INTRODUCTION: UNIFYING THEMES OF BIOLOGY

Chapter 1

Inquiring About the Natural World

• Biology is the scientific study of life

• Evolution is the basic principle of biology

• Scientific Inquiry is how we approach the study of life

Study of Life

• Look at the natural world by studying what living things do.

• Diversity and complexity

• How things are connected

Order

Evolutionary adaptation

Responseto theenvironment

ReproductionGrowth anddevelopment

Energyprocessing

Regulation

Fig. 1-3

Fig. 1-3a

Order

Fig. 1-3b

Evolutionaryadaptation

Fig. 1-3c

Responseto theenvironment

Fig. 1-3d

Reproduction

Fig. 1-3e

Growth and development

Fig. 1-3f

Energy processing

Fig. 1-3g

Regulation

Connecting Themes: Big Ideas

• More than just memorizing details

• Themes or Big Ideas will help you organize the information.

The Four Big Ideas: Big Idea 1

• The process of evolution drives the diversity and unity of life.• Makes sense of everything we know about living organisms

• Unifies biological concepts

Fig. 1-16

Cilia ofParamecium

Cross section of a cilium, as viewedwith an electron microscope

Cilia ofwindpipecells

15 µm 5 µm

0.1 µm

Fig. 1-15(a) DOMAIN BACTERIA

(b) DOMAIN ARCHAEA

(c) DOMAIN EUKARYA

Protists

Kingdom Fungi

KingdomPlantae

Kingdom Animalia

Fig. 1-14Species Genus Family Order Class Phylum Kingdom Domain

Ursus americanus(American black bear)

Ursus

Ursidae

Carnivora

Mammalia

Chordata

Animalia

Eukarya

The Four Big Ideas: Big Idea 2

• Biological Systems utilize free energy and molecular building blocks to grow, to reproduce, and to maintain homeostasis.• What are systems?

Fig. 1-4c

The biosphere

Fig. 1-4d

Ecosystems

Fig. 1-4e

Communities

Fig. 1-4f

Populations

Fig. 1-4g

Organisms

Fig. 1-4h

Organs andorgan systems

Fig. 1-4i

Tissues50 µm

Fig. 1-4j

Cells

Cell

10 µm

Fig. 1-4k

1 µm

Organelles

Fig. 1-4l

Atoms

Molecules

(a) Wings

(c) Neurons

(b) Bones

Infoldings ofmembrane

Mitochondrion

(d) Mitochondria0.5 µm100 µm

Fig. 1-6

Fig. 1-13a

Excess Dblocks a step

(a) Negative feedback

Negativefeedback

D

D D

D

C

B

A

Enzyme 1

Enzyme 2

Enzyme 3

–

Fig. 1-13b

Excess Zstimulates a step

(b) Positive feedback

Z

Positivefeedback

Enzyme 4

Enzyme 5

Enzyme 6Z

Z

Z

Y

X

W

+

The Four Big Ideas: Big Idea 3

• Living systems store, retrieve, transmit, and respond to life processes.

25 µm

Fig. 1-7

NucleicontainingDNA

Sperm cell

Egg cell

Fertilized eggwith DNA fromboth parents

Embryo’s cells withcopies of inherited DNA

Offspring with traitsinherited fromboth parents

Fig. 1-9

Fig. 1-10

Nucleus DNA

Cell

Nucleotide

(a) DNA double helix (b) Single strand of DNA

Fig. 1-11

The Four Big Ideas: Big Idea 4

• Biological systems interact, and these systems and their interactions possess complex processes.

Fig. 1-5

Sunlight

Ecosystem

Heat

Heat

Cyclingof

chemicalnutrients

Producers(plants and other photosynthetic

organisms)

Chemical energy

Consumers(such as animals)

Scientific Inquiry

•A search for information and explanation

•What is the scientific method?• What are its components?

Fig. 1-24a

Observations

Question

Hypothesis #1:Dead batteries

Hypothesis #2:Burnt-out bulb

Fig. 1-24b

Test prediction

Hypothesis #1:Dead batteries

Hypothesis #2:Burnt-out bulb

Test prediction

Prediction:Replacing batterieswill fix problem

Prediction:Replacing bulbwill fix problem

Test falsifies hypothesis Test does not falsify hypothesis