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Strategies of Life

Chapter 20Great Idea:

Living things use many different strategies to deal with the problems of acquiring and using matter and energy

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Chapter Outline

• The Organization of Living Things• What is Life• Classifying Living Things• Survival: A New Look at the Life

Around You• Strategies of Fungi• Strategies of Plants• Strategies of Animals

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The Organization of Living Things

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Ways of Thinking About Living Things

• Levels – Biosphere – Ecosystem – Community– Population– Organism– Anatomy &

physiology– Cellular– Molecular

• All levels complement each other

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What Is Life?

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The Characteristics of Life• High degree of order and

complexity• Part of larger systems of

matter and energy• Life depends on chemical

reactions in cells• Life requires liquid water• Organisms grow and develop• Regulate energy use• Share same genetic code, code

is heritable• All living things are descended

from a common ancestor

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Characteristics of Life

• Biology – “study of living things”• Defining living things

–By characteristics• Metabolic processes• Generative processes• Responsive processes• Control processes• Structural similarities

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Metabolic Processes

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Generative Processes

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iClicker Question

• Which one of the following represents a generative process?

• A enzymes• B individual adaptation• C nutrient uptake• D cell division

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Responsive Processes

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Control Processes

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iClicker Question

The overarching meaning of Homeostasis is

• A contributor and provider• B expand• C same or constant• D receiver

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iClicker Question

In response to a bacterial infection my body's thermostat is raised. I start to shiver and produce more body heat. When my body temperature reaches 101 degrees, I stop shivering and my body temperature stops going up. This is an example of:

A) Negative feedbackB) A malfunctioning control systemC) Positive feedbackD) A negative impact

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iClicker Question

Which of the following is an example of a positive feedback?

A) Shivering to warm up in a cold winter storm

B) A cruise control set on your car applies more gas when going up a hill

C) You sweat on a hot summer's day and the blood vessels in your skin vasodilate

D) You get cut and platelets form a clot. This in turn activates the fibrin clotting system and more blood forms clots

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Structural Similarities and Hierarchy

CommunityPopulation

OrganismOrgan

TissueCell

OrganellesMacromolecules

Atoms

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iClicker Question

• There are some places on the Earth’s surface where you won’t find living things.

– A True– B False

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iClicker Question

• At what level do most biologists today study living systems?

– A the level of organisms– B the level of molecules– C the level of the cell

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iClicker Question

• All life depends on chemical reactions that take place in cells.

– A True– B False

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iClicker Question

• All life requires liquid water.– A True– B False

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iClicker Question

• All living things on this planet share the same genetic code.

– A True– B False

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Classifying Living Things

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Cataloging Life

• Linnaean classification– Shared

characteristics

• Hierarchy– Kingdom– Phylum– Class– Order– Family– Genus– Species

• Binomial nomenclature

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Classifying Life (continued)

• Kingdoms–Monera–Protista–Fungi–Plants–Animals

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Classifying Human Beings

• Kingdom: Animals• Phylum: Chordates

–Subphylum: vertebrates• Class: Mammals• Order: Primates• Family: Hominid• Genus: Homo• Species: sapien

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Implications of Linnaean Classification

• Use of DNA• Similarity depends on time and

change• Classification results from real events

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iClicker Question

• How many kingdoms are currently recognized?

– A 2– B 3– C 4– D 5

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iClicker Question

• Whales and dolphins are actually mammals.

– A True– B False

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iClicker Question

• An interbreeding population of individual organisms that produces fertile offspring is called a:

– A species– B order– C phylum

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iClicker Question

• Which kingdom is most diverse?– A monera– B animals– C protests– D plants– E fungi

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Survival: A New Look at the Life Around You

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iClicker Question

• The field devoted to categorizing living things is called:

– A categonomy– B taxonomy– C branchology– D spectroscopy

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iClicker Question

• Which of the following species accounts for over half of all known species?

– A algae– B protozoa– C insects– D fungi– E monera

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Survival: A New Look at the Life Around You

• Autotrophs• Heterotrophs• Dealing with complexity• Two basic tasks

–Obtain and distribute molecules for energy

–Reproduce

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Strategies of Fungi

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Strategies of Fungi

• Growth– Filaments– Decomposers

• Structure– Mass of filaments

• Reproduction– Break filaments– Asexual reproduction

• spores

• Lichens– Two interdependent species

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iClicker Question

• What kind of cell can manufacture essential building blocks from simple molecules?

– A heterotrophs– B autotrophs– C technotrophs

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Strategies of Plants

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The Simplest Plants

• Phylum: Bryophytes• Structure

–No roots–Photosynthetic

• Reproduction–Sexual –Asexual

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Vascular Plants

• Phylum: vascular plants

• Structure– Roots, stems,

leaves– Control water loss

• Reproduction– Seedless– Gymnosperms– Angiosperms

• Sexual and asexual

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Angiosperm

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iClicker Question

• Much of the matter in the tissue in plants comes from:

– A soil– B water– C air

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iClicker Question

• Which of the following life forms carry out 50 to 90% of the Earth’s photosynthesis?

– A plants– B algae– C fungi

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Strategies of Animals

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Invertebrates

• Invertebrates–No backbone–Most diverse animals

• Arthropods–70% of known animal

species

• Structure–exoskeleton

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Vertebrates

• Organization–Ocean to terrestrial

• Evolution–Earliest fish–Bony Fish–Amphibians–Reptiles–Birds–Mammals