SELECTIVE BREEDING SELECTIVE BREEDING & GENETIC & GENETIC

ENGINEERINGENGINEERING3.f. Develop a logical argument for or 3.f. Develop a logical argument for or

against research conducted in selective against research conducted in selective breeding and genetic engineering, breeding and genetic engineering,

including (but not limited to) research including (but not limited to) research conducted in MS.conducted in MS.

Bellwork 1/5Bellwork 1/5

►Write a paragraph (at least 5 Write a paragraph (at least 5 sentences) about your Christmas sentences) about your Christmas BreakBreak

Selective Breeding & Genetic Selective Breeding & Genetic EngineeringEngineering

►Selective breeding & genetic Selective breeding & genetic engineering are 2 scientific techniques engineering are 2 scientific techniques in which humans try to produce in which humans try to produce offspring with desirable traitsoffspring with desirable traits

What is selective breeding?What is selective breeding?

►DefinitionDefinition::

Selective breeding is where Selective breeding is where humans select (chose) 2 humans select (chose) 2 animals with desired traits & animals with desired traits & breed (mate) them trying to breed (mate) them trying to produce offspring with the produce offspring with the desired traits of both parentsdesired traits of both parents

Selective BreedingSelective Breeding

►TypicallyTypically, strains which , strains which areare selectively selectively bred are bred are domesticateddomesticated

►Over many generationsOver many generations, the practice , the practice leads to the development of strains leads to the development of strains with the desired characteristicswith the desired characteristics

ExamplesExamples of selective of selective breedingbreeding

► Intentionally mating 2 dogs in order to Intentionally mating 2 dogs in order to achieve or eliminate a specific traitachieve or eliminate a specific trait

►A farmer saves seed from a hearty A farmer saves seed from a hearty crop to replant the next yearcrop to replant the next year

►Dogs are bred for competition or for Dogs are bred for competition or for huntinghunting

►Cows can be bred to increase muscle Cows can be bred to increase muscle mass or milk productionmass or milk production

Examples of Selective Examples of Selective BreedingBreeding

►Dogs are a good example of selective Dogs are a good example of selective breeding. Gamekeepers who hunted birds for breeding. Gamekeepers who hunted birds for leisure in the 1800s wanted a dog that didn’t leisure in the 1800s wanted a dog that didn’t actually exist. So, they selectively breed a actually exist. So, they selectively breed a mastiff and a bulldog to get the qualities that mastiff and a bulldog to get the qualities that they wanted. Mastiffs were big, strong & they wanted. Mastiffs were big, strong & good companions, but they lacked in speed good companions, but they lacked in speed and aggression. The bulldog however was and aggression. The bulldog however was aggressive and fast but lacked in strength. aggressive and fast but lacked in strength. The selective breeding process eventually The selective breeding process eventually produced a bullmastiff which was large, produced a bullmastiff which was large, quick, strong, & aggressivequick, strong, & aggressive

BullmastiffBullmastiff

Big, strong & good companion(not aggressive or fast)

Aggressive & fast (not big & strong)

Large, quick, strong & aggressive dog

When selective breedingthese 2 dogs, we get a Bullmastiff

Example of Selective Breeding Example of Selective Breeding in Cattlein Cattle

Brahman cattle: good resistance toheat, but poor meat

English shorthorn cattle: good beef, but poorheat resistance

When selecting to breedthese 2 animals we get aSanta Gertrudis cattle

Result = good beef ANDresistant to heat

Selective Breeding in CropsSelective Breeding in Crops

Selective Breeding of Lions & Selective Breeding of Lions & Tigers: LIGERTigers: LIGER

►Ligers are the world’s biggest catsLigers are the world’s biggest cats►Larger than their parents with the Larger than their parents with the

strength of a lion and speed of a tiger strength of a lion and speed of a tiger combinedcombined

►An average male liger stands almost An average male liger stands almost 12ft on its hind legs & weigh up to half 12ft on its hind legs & weigh up to half a ton (twice the weight of a wild lion or a ton (twice the weight of a wild lion or tiger)tiger)

How did the liger appear?How did the liger appear?

► If the father is a lion & the mother is a If the father is a lion & the mother is a tiger, the offspring are known as ligers tiger, the offspring are known as ligers and the pairing results in gigantismand the pairing results in gigantism

Strong but lacks speed

Fast but notas strong

Ligers are fast & strong& twice as big as parent

Why do people selectively breed Why do people selectively breed animals & plants?animals & plants?

►To make animals grow bigger, faster, To make animals grow bigger, faster, prettier & strongerprettier & stronger

►To make plants grow bigger, faster, To make plants grow bigger, faster, prettier & produce more cropsprettier & produce more crops

Pros of Selective BreedingPros of Selective Breeding

►BenefitsBenefits:: Farmers can produce crops with higher Farmers can produce crops with higher

yieldyield►More fruit or vegetables on a stalkMore fruit or vegetables on a stalk

Farmers can produce animals that grow Farmers can produce animals that grow more meat, more milk, more eggs, faster more meat, more milk, more eggs, faster & stronger& stronger

Can produce friendlier and prettier petsCan produce friendlier and prettier pets

ConsCons of Selective Breeding of Selective Breeding►DisadvantagesDisadvantages::

Loss of genes in a populationLoss of genes in a population►By not allowing some animals to breed, their genes could By not allowing some animals to breed, their genes could

be lost forever in a populationbe lost forever in a population► Take Hitler for example, he tried to kill all Jews, therefore, Take Hitler for example, he tried to kill all Jews, therefore,

trying to eliminate the genes and all Jews from the planettrying to eliminate the genes and all Jews from the planet Animal discomfortAnimal discomfort

► Farmers breed cows to have large utters, so now some Farmers breed cows to have large utters, so now some cows have difficulty walking & have health problemscows have difficulty walking & have health problems

► Some chickens are too heavy to stand, so they have to lay Some chickens are too heavy to stand, so they have to lay down all the timedown all the time

Can lead to inbreedingCan lead to inbreeding► In order to create a certain type of animal through In order to create a certain type of animal through

selective breeding, sometimes brothers & sisters of a selective breeding, sometimes brothers & sisters of a population will mate to pass on favorable traits, and this population will mate to pass on favorable traits, and this can lead to bad health problems for children of inbreedingcan lead to bad health problems for children of inbreeding

Bellwork 1/6

►Define selective breeding.

Classwork 1/6Classwork 1/6

►With a partner, come up with at least 5 With a partner, come up with at least 5 specific examples of selective specific examples of selective breeding.breeding. IF YOU FINISH BEFORE I CALL TIME, YOU IF YOU FINISH BEFORE I CALL TIME, YOU

NEED TO COME UP WITH MORE UNTIL I NEED TO COME UP WITH MORE UNTIL I TELL YOU TO STOP.TELL YOU TO STOP.

GENETIC ENGINEERINGGENETIC ENGINEERING

►Genetic engineering is a lot like Genetic engineering is a lot like selective breeding but a much faster selective breeding but a much faster processprocess

►Definition: taking favorable genes Definition: taking favorable genes from one organism and implanting it from one organism and implanting it into another organism’s DNAinto another organism’s DNA This This can only be done in a laboratory can only be done in a laboratory with with

special equipmentspecial equipment

ExamplesExamples of Genetic of Genetic EngineeringEngineering

1.1. People have taken the insulin making People have taken the insulin making gene from humans and inserted it gene from humans and inserted it into bacteria causing bacteria to into bacteria causing bacteria to make human insulinmake human insulin► Why?Why?

► Bacteria can reproduce quickly causing them Bacteria can reproduce quickly causing them to produce insulin at a much faster rateto produce insulin at a much faster rate

Examples of Genetic Examples of Genetic EngineeringEngineering

2.2. People have taken bad genes (genes People have taken bad genes (genes which cause cancer and other which cause cancer and other diseases) out of a person and diseases) out of a person and inserted healthy genes into a person inserted healthy genes into a person to cure them of diseasesto cure them of diseases► However, they may be cured of that However, they may be cured of that

disease but get another worse disease disease but get another worse disease because of being implanted with the because of being implanted with the other geneother gene

Examples of Genetic Examples of Genetic EngineeringEngineering

3.3. People have taken a weed resistant People have taken a weed resistant gene and inserted the gene into gene and inserted the gene into certain crop plantscertain crop plants► Now farmers can spray weed killer on Now farmers can spray weed killer on

the crops to kill the weeds, but the spray the crops to kill the weeds, but the spray will not affect the crops. will not affect the crops.

► The crops will grow better and bigger The crops will grow better and bigger because weeds do not take away because weeds do not take away sunlight, nutrients, and watersunlight, nutrients, and water► However, this gene has leaked over into the However, this gene has leaked over into the

weed population sometimes and caused the weed population sometimes and caused the weeds to be resistant to herbicides (weed weeds to be resistant to herbicides (weed killer spray)killer spray)

Examples of Genetic Examples of Genetic EngineeringEngineering

4.4. People have inserted genes into People have inserted genes into crops to make the crops resistant crops to make the crops resistant (poisonous) to pests, but are (poisonous) to pests, but are harmless to humans (we think)harmless to humans (we think)

Genetically Engineered FishGenetically Engineered Fish

►We have inserted genes into fish to We have inserted genes into fish to make them grow twice as big and make them grow twice as big and twice as fasttwice as fast

Genetically Engineered Genetically Engineered ChickensChickens

►We have inserted genes into chickens We have inserted genes into chickens to make them grow twice as big and to make them grow twice as big and twice as fast. They are so big they twice as fast. They are so big they can’t walk.can’t walk.

Genetically engineered cropsGenetically engineered crops

►Humans have injected genes into Humans have injected genes into crops to make them grow in colder crops to make them grow in colder environmentsenvironments

►Humans have injected genes into Humans have injected genes into crops to make them grow in dry crops to make them grow in dry (drought) environments(drought) environments

Genetically Engineered PigsGenetically Engineered Pigs

►Humans inject genes into pigs’ DNA in Humans inject genes into pigs’ DNA in order for the pig to grow human-like order for the pig to grow human-like organs, so people can transplant these organs, so people can transplant these organs into people who need themorgans into people who need them

Genetically Engineered MiceGenetically Engineered Mice►Humans inject genes into mice to Humans inject genes into mice to

make the mice grow human ears for make the mice grow human ears for cosmetic purposescosmetic purposes

Genetically Engineered Genetically Engineered VaccinesVaccines

►Genetically engineered vaccines Genetically engineered vaccines may may bebe safer because they do not use live safer because they do not use live viruses like traditional vaccines doviruses like traditional vaccines do

Genetic EngineeringGenetic Engineering

►Genetic engineering Genetic engineering may work may work wonders but wonders but it is all a process of it is all a process of manipulating the naturalmanipulating the natural

The Pros & Cons of The Pros & Cons of Genetic EngineeringGenetic Engineering

ProsPros Include: Include:

1.1. Humans have made crops with better Humans have made crops with better taste, nutrition, and growth ratetaste, nutrition, and growth rate

2.2. Humans have made pest resistant Humans have made pest resistant crops and crops with longer shelf lifecrops and crops with longer shelf life

3.3. Humans have been able to produce Humans have been able to produce new foodsnew foods► Foods which couldn’t be reproduced in Foods which couldn’t be reproduced in

naturenature

4.4. Humans can help cure certain diseaseHumans can help cure certain disease5.5. Boosts positive traits and suppress Boosts positive traits and suppress

negative onesnegative ones

ConsCons Include: Include:

1.1. By making plants bigger, taste better, and By making plants bigger, taste better, and better appearance we have accidentally better appearance we have accidentally made some crops allergenic to peoplemade some crops allergenic to people

2.2. By making plants bigger, taste better, and By making plants bigger, taste better, and better appearance we have accidentally better appearance we have accidentally made some crops have less nutritional made some crops have less nutritional valuevalue

3.3. Accidental gene transferAccidental gene transfer► Such as when we inserted genes into crops to Such as when we inserted genes into crops to

make them resistant to pest or herbicides, the make them resistant to pest or herbicides, the genes leaked over into weeds and made them genes leaked over into weeds and made them resistant to pest and herbicides tooresistant to pest and herbicides too

ConsCons Include: Include:

4.4. Genetic engineering in human beings can Genetic engineering in human beings can have certain side effectshave certain side effects► While treating one defector disease, the genetic While treating one defector disease, the genetic

engineering may lead to another disease which engineering may lead to another disease which could be worsecould be worse

5.5. What’s next?What’s next?► Will people try to insert genes into babies to Will people try to insert genes into babies to

have children which are smarter, muscular, have children which are smarter, muscular, prettier, certain color eyes, certain color hair, prettier, certain color eyes, certain color hair, and talentedand talented

6.6. Playing God…Playing God…

QuizQuiz

1.1. Define selective breeding.Define selective breeding.2.2. List 3 examples of selective breeding.List 3 examples of selective breeding.3.3. List 2 benefits of selective breeding.List 2 benefits of selective breeding.4.4. List 2 disadvantages of selective List 2 disadvantages of selective

breeding.breeding.5.5. Define genetic engineering.Define genetic engineering.6.6. List 3 examples of genetic engineering.List 3 examples of genetic engineering.7.7. List 2 benefits of genetic engineering.List 2 benefits of genetic engineering.8.8. List 2 disadvantages of genetic List 2 disadvantages of genetic

engineering.engineering.

Bellwork 1/7Bellwork 1/7

►List benefits and disadvantages of List benefits and disadvantages of selective breeding.selective breeding.

►List benefits and disadvantages of List benefits and disadvantages of genetic engineering.genetic engineering.