Biology and YouBiology and You

I. I. Themes of BiologyThemes of Biology

Biology-the study of lifeBiology-the study of life

A. A. Living things share these Living things share these PROPERTIES OF LIFE:PROPERTIES OF LIFE:

Cellular Structure and FunctionCellular Structure and Function ReproductionReproduction MetabolismMetabolism HomeostasisHomeostasis HeredityHeredity EvolutionEvolution InterdependenceInterdependence

The Latin meaning of The Latin meaning of sciencescience is is “ “to knowto know””

1. Cellular Structure and 1. Cellular Structure and FunctionFunction

All living things are made of All living things are made of one or more one or more cellscells..

Cells-smallest unit capable Cells-smallest unit capable of all life functionsof all life functions

2. Reproduction2. Reproduction

All living things can All living things can reproduce. reproduce.

BacteriaBacteria can reproduce can reproduce as fast as as fast as every 15 every 15 minutes.minutes.

Bristlecone PinesBristlecone Pines can can be be 5,000 years5,000 years old and old and still be forming seeds.still be forming seeds.

3. Metabolism3. Metabolism

Living things carry out many Living things carry out many different different chemical reactions chemical reactions in order to obtain in order to obtain and use and use ENERGYENERGY to run the processes to run the processes of life.of life.

Metabolism is the Metabolism is the sum of all of the sum of all of the chemical reactions carried out in an chemical reactions carried out in an organism.organism.

3. Metabolism3. Metabolism

Almost all the energy used by living Almost all the energy used by living organisms is originally captured from organisms is originally captured from sunlightsunlight. .

PHOTOSYNTHESIS is the process that PHOTOSYNTHESIS is the process that plants, algae and some bacteria use to plants, algae and some bacteria use to capture solar energy and use it to make capture solar energy and use it to make food.food.

Energy flows from Energy flows from sunsun to to plantsplants, , plantsplants to to plant-eatersplant-eaters, , plant eatersplant eaters to to meat-eatersmeat-eaters..

4. Homeostasis4. Homeostasis

All organisms must All organisms must maintain a stable internal maintain a stable internal environmentenvironment to function properly. This to function properly. This maintenance of stable conditions is called maintenance of stable conditions is called HOMEOSTASIS.HOMEOSTASIS.

Examples: Examples: BODY TEMPERATURE, FLUIDS, PH, BODY TEMPERATURE, FLUIDS, PH, SUGAR LEVELSSUGAR LEVELS

5. Heredity5. Heredity

All living things are able to pass on All living things are able to pass on traits to their traits to their offspringoffspring through genes that are passed from through genes that are passed from parent to offspring each generation.parent to offspring each generation.

A gene is A gene is the basic unit of hereditythe basic unit of heredity and are coded and are coded in a molecule called in a molecule called deoxyribonucleic acid (DNA).deoxyribonucleic acid (DNA).

The passing of traits from parent to offspring is The passing of traits from parent to offspring is called called heredity.heredity.

Mutation –Mutation –a change in the DNA of a genea change in the DNA of a gene Example: Example: Sickle Cell AnemiaSickle Cell Anemia

6. Evolution6. Evolution Change Change in the inherited traits of species over in the inherited traits of species over

generations generations is called is called evolutionevolution.. Species Species is a group of genetically similar is a group of genetically similar

organisms that can produce fertile offspringorganisms that can produce fertile offspring.. Charles DarwinCharles Darwin-- 19th century naturalist 19th century naturalist

known as the father of evolution; provided a known as the father of evolution; provided a consistent explanation for life’s diversityconsistent explanation for life’s diversity..

Natural SelectionNatural Selection is the process in is the process in which organisms with favorable genes are which organisms with favorable genes are more likely to survive to reproduce more likely to survive to reproduce

7. Interdependence7. Interdependence Organisms in a biological Organisms in a biological

community live and interact community live and interact with other organismswith other organisms..

EcologyEcology-the branch of -the branch of biology that studies the biology that studies the interactions of organisms interactions of organisms with one another and with with one another and with the nonliving part of their the nonliving part of their environment.environment.

. . Biology and Your WorldBiology and Your World

What world problems are What world problems are biologists working to solve?biologists working to solve?

Preserving Our EnvironmentPreserving Our Environment

Conservation and Preservation are now Conservation and Preservation are now everyday activities of government, industry everyday activities of government, industry and individuals. and individuals.

Improving Food SupplyImproving Food Supply

One of greatest impacts of modern biology One of greatest impacts of modern biology on society in recent years has been the on society in recent years has been the genetic engineering of crop plants.genetic engineering of crop plants.

Genetic engineering has made some crop Genetic engineering has made some crop plants resistant to herbicides, some crop plants resistant to herbicides, some crop plants poisonous to insect pests, but not plants poisonous to insect pests, but not humans and has produced new varieties of humans and has produced new varieties of crop plants.crop plants.

Understanding the Human Understanding the Human GenomeGenome

June 26, 2000: June 26, 2000: the announcement of the the announcement of the completion of the sequencing of the human completion of the sequencing of the human genome. genome.

A A genomegenome is the complete genetic material is the complete genetic material contained in an individual.contained in an individual.

The human genome contains The human genome contains

3 billion individual units.3 billion individual units.

Fighting DiseaseFighting Disease

AIDSAIDS-caused by HIV; destroys and attacks the -caused by HIV; destroys and attacks the immune system.immune system.

CancerCancer- a growth defect in cells.- a growth defect in cells.

3. Emerging Diseases- 3. Emerging Diseases- West Nile VirusWest Nile Virus is transmitted by mosquitoes is transmitted by mosquitoes and is known to infect humans, birds, horses, and is known to infect humans, birds, horses, and other animals.and other animals.

Mad Cow DiseaseMad Cow Disease is a caused by eating is a caused by eating the body parts of infected animals.the body parts of infected animals.

Fighting DiseaseFighting Disease

Gene TherapyGene Therapy- Searching for ways to introduce - Searching for ways to introduce “healthy” genes into people that are suffering from “healthy” genes into people that are suffering from hereditary disorders.hereditary disorders.

a.a. Cystic Fibrosis- Cystic Fibrosis-a fatal disorder in which mucus a fatal disorder in which mucus clogs passages in many of the body’s organs.clogs passages in many of the body’s organs.

b. b. Gene TherapyGene Therapy-the replacement of a defective -the replacement of a defective gene with a normal version.gene with a normal version.

Steps to the Scientific Method Steps to the Scientific Method – Title Title – Question/ProblemQuestion/Problem– Research Research – Hypothesis/Prediction Hypothesis/Prediction – Experiment/Test Experiment/Test

Control, Independent & Dependent Variable Control, Independent & Dependent Variable

– Data/Analysis Data/Analysis – Conclusion Conclusion

III. Scientific ProcessesIII. Scientific Processes

A. A. Solving Scientific PuzzlesSolving Scientific Puzzles

OBSERVATIONOBSERVATION- the act of noting or - the act of noting or perceiving objects or events using the perceiving objects or events using the

senses. senses.

B. B. Stages of Scientific Stages of Scientific ObservationsObservations

1. 1. Collecting ObservationsCollecting Observations 2. 2. Asking QuestionsAsking Questions Talk to other scientists, read scientific reportsTalk to other scientists, read scientific reports

3. Forming Hypotheses3. Forming Hypotheses HypothesisHypothesis is an explanation that might be true- a is an explanation that might be true- a

statement that can be tested by additional statement that can be tested by additional observations.observations.

PredictionPrediction is the expected outcome of a test . is the expected outcome of a test .

Stages of Scientific Observations Stages of Scientific Observations Con’tCon’t

4. Confirming Predictions4. Confirming Predictions ExperimentExperiment is a planned procedure to test a is a planned procedure to test a

hypothesis.hypothesis. Control GroupControl Group is a group in the experiment that is a group in the experiment that

receives NO experimental treatment.receives NO experimental treatment. Independent variableIndependent variable is what is changed in an is what is changed in an

experiment.experiment. Dependent variableDependent variable is the variable that is is the variable that is

measured in the experiment.measured in the experiment.

Stages of Scientific Observations Stages of Scientific Observations Con’tCon’t

5. Drawing Conclusions5. Drawing Conclusions The hypothesis may be accepted or The hypothesis may be accepted or

rejected.rejected.

Scientific ExplanationsScientific Explanations- - The Development of a TheoryThe Development of a Theory

A theory is a set of related hypothesis that A theory is a set of related hypothesis that have been tested and confirmed many times have been tested and confirmed many times by many scientists. by many scientists.

A theory unites and explains a broad range A theory unites and explains a broad range of observations.of observations.