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The Science of LifeThe Science of Life

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What is Biology?What is Biology?BiologyBiology is the study of all is the study of all living thingsliving things

Living things are called Living things are called organismsorganismsOrganisms include bacteria, Organisms include bacteria, protists, fungi, plants, & protists, fungi, plants, & animalsanimals

Biology and…..Biology and…..• Biology and YouBiology and You

-healthy foods-healthy foods

-exercise and reproduction-exercise and reproduction

-DNA-DNA• Biology and SocietyBiology and Society

-ecosystems-ecosystems

-animal/plant interactions-animal/plant interactions

-pollution and water supply-pollution and water supply

-curing disease-curing disease

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All Living Things Share All Living Things Share Common Common

CharacteristicsCharacteristics1.1. Basic Unit is the Basic Unit is the Cell Cell and and

cells arecells are organized. organized.

2.2. They They Reproduce Reproduce and have and have DNA.DNA.

3.3. Grow & DevelopGrow & Develop

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Common Common CharacteristicsCharacteristics

4. Obtain & Use Materials & 4. Obtain & Use Materials & Energy Energy (Metabolism)(Metabolism)5.5.RespondRespond To Their Environment To Their Environment6.6.Maintain A Maintain A Stable Internal Stable Internal Environment (Homeostasis)Environment (Homeostasis)7.7.AS A GROUPAS A GROUP, Living Things , Living Things EvolveEvolve, That Is They Change Over , That Is They Change Over TimeTime

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Characteristics of Characteristics of OrganismsOrganisms

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All Organisms are All Organisms are made of Cells and made of Cells and

are organizedare organized

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Facts About CellsFacts About CellsCells are the Cells are the smallest living smallest living unitunit of an organism of an organism

All cells contain living All cells contain living material called material called cytoplasmcytoplasm

All cells are surrounded by a All cells are surrounded by a cell membranecell membrane that controls that controls what enters & leaves the cellwhat enters & leaves the cell

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More Cell FactsMore Cell FactsCells are complex & Cells are complex & highly highly organizedorganized

Cells have parts Cells have parts called called organellesorganelles that that do different jobsdo different jobs

e.g. Chloroplasts in e.g. Chloroplasts in plants make sugarsplants make sugars

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More Cell FactsMore Cell FactsThe simplest cells The simplest cells are called are called ProkaryotesProkaryotes

These cells These cells DO NOT DO NOT have a nucleus or have a nucleus or membrane-bound membrane-bound organellesorganelles

BacteriaBacteria are are examplesexamples

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More Cell FactsMore Cell FactsMore complex cells More complex cells are called are called EukaryotesEukaryotes

These cells These cells DO have DO have a nucleus and a nucleus and membrane-bound membrane-bound organellesorganelles

Plants, animals, Plants, animals, protists, & fungiprotists, & fungi are are examplesexamples

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Organisms are Grouped by Organisms are Grouped by their Number of Cellstheir Number of Cells

Unicellular OrganismsUnicellular Organisms– Living Organism Made Up Living Organism Made Up

Of One CellOf One Cell

Multicellular Multicellular OrganismsOrganisms– Living Organism Made Up Living Organism Made Up

Of Many, Specialized CellsOf Many, Specialized Cells

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Levels of Levels of organizationorganization

AtomsAtomsMoleculesMoleculesOrganellesOrganellesCellsCells TissuesTissuesOrgansOrgansSystemSystemOrganismOrganism

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Organisms Reproduce to Organisms Reproduce to Pass on their Genetic TraitsPass on their Genetic Traits

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Two Types of Two Types of ReproductionReproduction

Sexual Sexual ReproductionReproductionInvolves 2 Involves 2 parentsparents

Egg fertilized by Egg fertilized by sperm to make a sperm to make a ZYGOTEZYGOTE

Offspring Offspring DIFFERENT from DIFFERENT from parentsparents

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Two Types of Two Types of ReproductionReproduction

Asexual Asexual ReproductionReproductionInvolves a single Involves a single organism or cellorganism or cell

Cell dividesCell divides

Offspring Offspring IDENTICAL to IDENTICAL to parentparent

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Genetic CodeGenetic Code

DNADNA ( (deoxyribose nucleic deoxyribose nucleic acidacid) carries the genetic code ) carries the genetic code for all organismsfor all organisms

All organismsAll organisms contain DNA contain DNA

DNA DNA codes for the proteinscodes for the proteins that make up cells & do all that make up cells & do all the workthe work

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Organisms Grow & Organisms Grow & DevelopDevelop

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Growth & DevelopmentGrowth & Development

Organisms Organisms growgrow by by producing MORE producing MORE CELLS & by cell CELLS & by cell ENLARGEMENTENLARGEMENT

Organisms Organisms developdevelop as they mature into as they mature into an adult organisman adult organism

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MetabolismMetabolism

Sum of all the chemical Sum of all the chemical reactions in an organismreactions in an organism

All All require energyrequire energy

SunlightSunlight is the ultimate is the ultimate energy for life on Earth energy for life on Earth

Photosynthesis

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MetabolismMetabolism

Cellular RespirationCellular Respiration – Cells releasing the chemical Cells releasing the chemical

energy stored in foodsenergy stored in foods

6O6O22 + C + C66HH1212OO66 6CO 6CO22 + + 6H6H22OO

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Organisms Respond to Organisms Respond to StimuliStimuli

Organisms Organisms RespondRespond to to stimulistimuli (Temperature, Water, (Temperature, Water, Food Supplies, etc.) Food Supplies, etc.) In Order In Order To Survive & ReproduceTo Survive & Reproduce

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HomeostasisHomeostasisKeeping The Internal Environment Keeping The Internal Environment (Homeostasis)(Homeostasis) Of The Cell or Organism Of The Cell or Organism Within The Ranges Required For LifeWithin The Ranges Required For LifeStable internal conditions of Stable internal conditions of pH, pH, temperature, water balance, etctemperature, water balance, etc..

Organisms must Organisms must have a way of have a way of REGULATINGREGULATING themselves in order themselves in order to maintain a stable to maintain a stable internal internal environmentenvironment..

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Living Things EvolveLiving Things Evolve

Groups Of OrganismsGroups Of Organisms (Not Individuals) (Not Individuals) Change Over Time In Change Over Time In Order To Survive Order To Survive Within Changing Within Changing Environments.Environments.Fossil recordsFossil records show show changes in groups of changes in groups of organismsorganismsDNADNA and and MUTATIONSMUTATIONS are are important in evolution.important in evolution.

Major Themes in BiologyMajor Themes in Biology

Unity and DiversityUnity and Diversity

- even though life is so diverse, it is - even though life is so diverse, it is characterized by the features that all living characterized by the features that all living things share.things share.

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Three Domains of Life

Eukarya – largest domain.

Archea – live in extreme environments.

Bacteria –

ALL COME A FROM A COMMON ANCESTOR.

Major Themes in BiologyMajor Themes in Biology

Interdependence of OrganismsInterdependence of Organisms

Ecology – studies how living and non-Ecology – studies how living and non-living things (environment).living things (environment).

Ecosystems – communities of living Ecosystems – communities of living species and their physical environmentsspecies and their physical environments

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Major Themes in BiologyMajor Themes in BiologyEvolution of LifeEvolution of Life

Individual organisms change during their lifetime, but Individual organisms change during their lifetime, but their basic genetic plan does not.their basic genetic plan does not.

Natural selection – organisms with favorable traits will Natural selection – organisms with favorable traits will survive to pass those traits on to their offspring. They survive to pass those traits on to their offspring. They are better able to survive than those lacking the traits.are better able to survive than those lacking the traits.

Traits come from genes and DNA.Traits come from genes and DNA.

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