Chapter 1 The Study of Life Lecture Outline See PowerPoint Image Slides for all figures and tables pre-inserted into PowerPoint without notes. Copyright.

Chapter 1The Study of LifeLecture Outline

See PowerPoint Image Slidesfor all figures and tables pre-inserted into

PowerPoint without notes.

Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display.

Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display.

planet Earth

mushroom on northernforest floor

male peacockdisplaying feathershumans in a city

giant sequoia

Masai giraffes

monarch butterflyfeeding on nectar

(sequoia): © Robert Glusic/Getty RF; (mushroom): © IT Stock/Age Fotostock RF; (peacock): © Brand X Pictures/PunchStock RF; (humans): © Heath Korvola/UpperCut Images/Getty RF; (giraffes): © Dr. Sylvia S. Mader; (butterfly): © Creatas/PunchStock RF; (Earth): © Ingram Publishing/Alamy RF

1.1 The Characteristics of Life

• Life exists almost everywhere on the planet Earth.

• Earth possesses a great variety of diverse life forms.

• All living things have certain characteristics in common.

Living Things:

• Are organized• Acquire materials and energy• Reproduce• Respond to stimuli• Are homeostatic• Grow and develop• Have the capacity to adapt

• Living things are organized in a hierarchy of levels.

• A cell is the smallest unit of life.

• A tissue is a group of similar cells that perform a particular function.

• Several tissues join together to form an organ.

• Organs work together to form an organ system.

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nerve cellplant cell

nerve tissue

tree

Organisms

Organ Systems

organ system

Organs

Tissues

Cells

human

leaf tissues

Atoms

Molecules

leaf brain

DNA molecule

• Living things need an outside source of materials and energy to maintain their organization and carry on life’s other activities.

• Energy – capacity to do work

• Growth – increase is size or number of cells

• Development – changes that take place from conception to death

1.2 The Classification of Living Things

• Living organisms are assigned to groups based upon their similarities.

• Systematics is the discipline of identifying and classifying organisms.

Domains

• Domains are the largest classification category.

• Biologists assign organisms to one of three domains based on biochemical and genetic evidence.

• Prokaryotes lack a membrane-bounded nucleus.

• Eukaryotes have a membrane-bounded nucleus.

Domain Archaea

• Archaea are unicellular prokaryotes.

• Archaea can be found in environments that are too hostile for other life forms.

Domain Bacteria• Bacteria are unicellular

prokaryotes.

• Bacteria are found almost everywhere on the planet Earth.

• Some bacteria cause disease but many are beneficial.

Domain Eukarya

• The cells of all eukaryotes have a membrane-bound nucleus.

• Members of the Domain Eukarya are further categorized into one of four Kingdoms.

• Kingdom Protista – may be several kingdoms• Kingdom Fungi• Kingdom Plantae• Kingdom Animalia

Representative Organisms

black bread mold yeast mushroom bracket fungus

sea star earthworm finch raccoon

moss fern pine tree

paramecium euglenoid slime mold dinoflagellate

Kingdom Organization Type of Nutrition

Protista

Fungi

Plantae

Animalia

Absorb food

Ingest food

c. Eukaryotes are divided into four kingdoms.

DOMAIN EUKARYA

Complex single cell,some multicellular

Some unicellular,most multicellularfilamentous formswith specializedcomplex cells

Multicellular formwith specializedcomplex cells

Multicellular formwith specializedcomplex cells

Absorb,photosynthesize,or ingest food

Photosynthesizefood

nonwoodyflowering plant

Protozoans,algae, water molds,and slime molds

Molds, yeasts,and mushrooms

Mosses, ferns,nonwoody andwoody floweringplants

Invertebrates,fishes, reptiles,amphibians, birds,and mammals

Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display.

Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display.

Representative Organisms

black bread mold yeast mushroom bracket fungus

sea star earthworm finch raccoon

moss fern pine tree

paramecium euglenoid slime mold dinoflagellate

Kingdom Organization Type of Nutrition

Protista

Fungi

Plantae

Animalia

Absorb food

Ingest food

Methanosarcina mazei

1.6 m 1.5 m

DOMAIN BACTERIA

Escherichia coli

a. Archaea are capable of living in extreme environments. b. Bacteria are found nearly everywhere.

c. Eukaryotes are divided into four kingdoms.

DOMAIN ARCHAEA

DOMAIN EUKARYA

Complex single cell,some multicellular

Some unicellular,most multicellularfilamentous formswith specializedcomplex cells

Multicellular formwith specializedcomplex cells

Multicellular formwith specializedcomplex cells

Absorb,photosynthesize,or ingest food

Photosynthesizefood

nonwoodyflowering plant

Protozoans,algae, water molds,and slime molds

Molds, yeasts,and mushrooms

Mosses, ferns,nonwoody andwoody floweringplants

Invertebrates,fishes, reptiles,amphibians, birds,and mammals

(bacteria): © A.B. Dowsett/SPL/Photo Researchers, Inc.; (archaean): © Ralph Robinson/Visuals Unlimited

Categories of Classification

DomainKingdomPhylumClassOrderFamilyGenusSpecies Least inclusive

Most inclusive

Categories of Classification

Scientific Names

• Taxonomy is the assignment of a binomial to each species.

• Binomial (two name)– Genus name, species name– Genus capitalized, both words in italics

–Examples: »Homo sapiens»Pisum sativum»Felis domesticus

1.3 The Organization of the Biosphere

• Biosphere – The zone of air, land, and water at the surface

of the Earth where living organisms are found.

• Population– All the members of a species within a

particular area

• Community– All the different populations in the same area

1.3 The Organization of the Biosphere

• Ecosystem– Community interact among themselves and

with the physical environment (soil, atmosphere, etc.)

– Characterized by• Chemical cycling – chemicals move from 1 species

to another• Energy flow – energy flows from the sun, through

plants, through the food chain

heat

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Chemical cycling

heat

heat

heat

heat

heat

Energy flowWASTE MATERIAL,DEATH,

AND DECOMPOSITION

solarenergy

• Climate largely determines where different ecosystems are found around the globe

• The two most biologically diverse ecosystems—tropical rain forests and coral reefs—occur where solar energy is most abundant.

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detritus

phytoplankton

corals

sponges

white shark

bar jack

queen angelfish

parrotfish

surgeonfish

sea grass

greatbarracuda

attachedalgae

greenmoray

yellowtailsnapper

Spanishhogfish

yellowjack

seastar

Bermudachub

yellowtaildamselfish

foureyebutterfly fish

seaurchin

zooplankton

spinylobster

The Human Species

• The human species tends to modify existing ecosystems for its own purposes.

• Tropical rain forests and coral reefs are severely threatened as global human population increases.

• Human begins depends on healthy ecosystems for food, medicine, and raw materials.

Biodiversity

• Ecompasses– Total number of species– The variability in their genes– The ecosystems in which they live

• As many as 5-30 million species on Earth

• Human activities cause the extinction of about 400 species per day.

1.4 The Process of Science

• Biology is the scientific study of life.

• Biologists—and all scientists—generally test hypotheses using the scientific method.

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Observation

Hypothesis

Experiment/Observations

New observationsare made, and previous

data are studied.

Input from various sourcesis used to formulate a

testable statement.

The hypothesis istested by experiment

or further observations.

Many experiments andobservations support a

theory.

Scientific Theory

Conclusion

The results are analyzed,and the hypothesis issupported or rejected.

Courtesy Leica Microsystems, Inc.

The Process of Science

• Inductive reasoning occurs whenever a person uses creative thinking to combine isolated f– A scientist comes up with a hypothesis, a

tentative explanation for the natural event. acts into a cohesive whole.

• To determine how to test a hypothesis, a scientist uses deductive reasoning.– Involves “if, then” logic

Scientific theory

• Concepts that join together well-supported and related hypotheses.

• In science, a theory is supported by a broad range of observations, experiments, and data.– Examples – Cell , homeostasis, gene,

ecosystem, and evolution

• The theory of evolution is the unifying concept of biology.

A Controlled Study

• Experiments in controlled studies have two types of groups:

• Control Group – receives no treatment• Experimental Group – receives treatment

The Experiment

• HYPOTHESIS: A pigeon pea/winter wheat rotation will cause winter wheat production to increase as well as or better than the use of nitrogen fertilizer.

• PREDICTION: Wheat production (biomass) following the growth of pigeon peas will surpass wheat biomass following nitrogen fertilizer treatment.

90 kg of nitrogen/ha Pigeon pea/winter wheat rotation

Control pot

no fertilization treatment

Test pot

45 kg of nitrogen/ha

a. Control pot and three types of test pots

Test pot Test pot

Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display.

Courtesy Jim Bidlack

• Control – no fertilization treatment• Tests

– Winter wheat in soil treated with nitrogen fertilizer (45kg/ha)

– Winter wheat in soil treated with nitrogen fertilizer (90kg/ha)

– Pigeon pea plants tilled into soil and then winter wheat planted

• All other conditions the same in all pots

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b. Results

20

10

5

0year 1 year 2 year 3

= no fertilization treatment

= 45 kg of nitrogen/ha

Control Pots

= 90 kg of nitrogen/ha

= Pigeon pea/winter wheat rotation

Wh

eat

Bio

ma

ss (

gra

ms/

po

t)15

Test Pots

90 kg of nitrogen/ha Pigeon pea/winter wheat rotation

Control pot

no fertilization treatment

Test pot

45 kg of nitrogen/ha

b. Results

20

10

5

0year 1 year 2 year 3

= no fertilization treatment

= 45 kg of nitrogen/ha

Control Pots

= 90 kg of nitrogen/ha

= Pigeon pea/winter wheat rotation

Wh

ea

t B

iom

ass

(g

ram

s/p

ot)

15

a. Control pot and three types of test pots

Test pot Test pot

Test Pots

Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display.

Courtesy Jim Bidlack

The Experiment

• Conclusion: The hypothesis was supported. At the end of two years, the yield of winter wheat following a pigeon pea/winter wheat rotation was better than for the other type pots.

1.5 Science and Social Responsibility

• Technology is the application of knowledge for a practical purpose.

• Technology has both benefits and drawbacks.

• Ethical and moral issues surrounding the use of technology must be decided by everyone. – Responsibility for how to use scientific technology must

reside with people from all walks of life, not with scientists alone