G7 I can list examples of changes in genetic traits due to natural and manmade influences What is Natural Selection Write it on your white board Which of the following is an example of Natural Selection ID: 419201
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Slide1
Natural and Artificial Selection
G7- I can list examples of changes in genetic traits due to natural and manmade influencesSlide2
What is Natural Selection?
Write it on your white boardSlide3
Which of the following is an example of Natural Selection?
Humans breed cows to produce 8 gallons of milk per day
Farmers plant only the biggest, tastiest ears of corn and as a result will get more big, tasty ears of corn
Horses were once short and slow to escape predators. Today they are taller and run very quickly, making it easier to escape predatorsSlide4
What is Artificial Selection?
Write it on your white boardSlide5
Which of the following is an example of Artificial Selection?
Millions of years ago, plants were short and did not have root systems, but now plants can grow very tall and have large root systems
Over time, birds bones have become hollow making them lighter for easy flying
Tomatoes at the grocery store stay fresher longer because humans like eating fresher tomatoes and therefore grow only fresh tomatoesSlide6
Read the following:
“
Antibiotics work to kill
bacteria. Bacteria
are single-cell organisms. If bacteria make it past
our immune systems
and start reproducing inside our bodies, they cause disease. We want to kill the bacteria to eliminate the disease
.”
Raise your hand if you have ever taken antibiotics for anythingSlide7
Read the following:
“An
antibiotic is a
selective poison
. It has been chosen so that it will kill the desired bacteria, but not the
cells
in your body. Each different type of antibiotic affects different bacteria in different ways. For example, an antibiotic might
stop
a bacterium's ability to turn
sugar
into energy, or its ability to
build
its cell wall. When this happens, the bacterium dies instead of reproducing
.”
Summarize the idea of this paragraph with your partnerSlide8
Read the following:
“
Antibiotics do not work on
viruses because
viruses are not alive. A bacterium is a living, reproducing
organism.
A virus is just a piece of
DNA(or
RNA). A virus injects its DNA into a living cell and has that cell reproduce more of the viral DNA. With a virus there is nothing to "kill," so antibiotics don't work on
it”
Can Viruses (or other non-living things) Adapt? Why do you think this?Slide9
Think about “Survival of the fittest.”
New antibiotics always have to be created to treat colds and flu. Why do you think this happens? Slide10
Antibiotics
Why is it a mistake to take antibiotics for viral cold/flu?
Bacteria becomes resistant
The virus becomes resistant
Antibiotics are expensive
Antibiotics taste badSlide11
Peppered Moths and Adaptations
http://www.youtube.com/watch?v=LyRA807djLc
What characteristic of moths was “selected” to survive
w
hen the soot turned the trees black? Slide12
Peppered Moths and Adaptations
Because the trees turned black, were there more black peppered moths, or white peppered moths in the next generation? Why is this?Slide13
Farmers are always changing the types of insecticide to fight pests because…
Insecticides actually make insects healthier
Chemical labs make more money by making new insecticides
This is a tradition that farmers always follow
Insects develop resistance to old insecticidesSlide14
Write down two examples of adaptations that organisms have changed because of Natural SelectionSlide15
Write down two examples of adaptations in organisms that have changed because of Artificial SelectionSlide16
A tangelo is a cross between a tangerine and a grapefruit. Why do plant Scientists make genetic crosses like this?
The new offspring may have desirable traits
They
are accidents that scientists cannot prevent from
happening
Tangelos are better than tangerines or grapefruit
We need to keep discovering new fruits because the fruits we have are not healthy enoughSlide17
Human beings walk upright. What adaptive advantage does this provide?
We run faster than other animals
We see in more color than other animals
It allows us to use our hands
It gives us the ability to hear better
*Is this adaptation a result of Natural Selection or Artificial Selection?Slide18
Asexual v. Sexual
A disastrous infection has the capability to wipe out an entire group of organisms, but some organisms may survive if they have the right traits for survival.
Does an Asexual population have a better or worse chance of surviving the disastrous infection than a Sexual population?
Discuss what you think with a partner and write it on your whiteboard