Discrepant Events: Biology
B. Diversity of Living Things:
When asking students what animals and mammals that live in polar-regions they
often don't realize the many mammals present especially marine mammals.
http://beyondpenguins.nsdl.org/issue/column.php?date=January2009&departmen
tid=professional&columnid=professional!misconceptions
This website has many activities and ideas. Even if they are somewhat elementary,
they can be adapted to more senior level biology.
C. Evolution
When discussing adaptations introducing the topic of 'sex-changing' fish
http://www.marinebiology.org/fish.htm actually gets their attention. I would
attempt to find pictures or videos to have a visual as we discuss the topic. I would
introduce the topic in a way that sparks a debate as to whether this could actually
occur. Once we have debated a bit and possibly made a list of how this adaptation
would benefit the species, I would introduce the types of fishes that have this ability.
We would then brainstorm as to how this mechanism of 'sex-changing' could occur
and then follow-up with a little more research.
http://animals.nationalgeographic.com/animals/fish/parrot-fish.html
D. Genetic Processes
Posing the statement: Cow's milk will improve the diet of infants in African tribes.
Most students will say this is true. I would use this to discuss the lac operon in the
genetics unit.
http://www.jstor.org.myaccess.library.utoronto.ca/stable/4449456?seq=4
Indigenous people tend to lack the gene that codes for the enzyme lactase, which is
responsible for the breakdown of lactose.
E. Animal Structures and Function
http://sites.google.com/site/sed695b/projects/discrepant-events/absorption-pretzel-predictions
I think this activity is intriguing in that it is a challenge. Students must predict how
many pretzels they can eat in one minute and then they must attempt to do this.
They will not have water and therefore their predication will likely be much greater
than the number they can actually eat. This activity could be a lead-in to the topic of
digestion.
F. Plants in the Natural Environment
http://www.suite101.com/content/discrepant-events-and-groundwater-a41170
Today's students have always been exposed to bottled water. The phenomenon
surfaced in the early 1990's and from there ensued a mass appeal. Today it common
for people to prefer drinking bottled water, rather than drinking their tap water.
This activity challenges student's perceptions of water purification and their
understanding of the origin of purified water. This lesson would be incorporated
within the lesson regarding the water cycle. F3.4 SB13C.
http://www.csun.edu/scied/3-field%20study/hyperion/index.htm
Perhaps this link could be used as a template for a field trip as a follow-up activity to
the activity above.
Plant Anatomy Growth and Function: A Real “Corn-undrum” plants grow faster in
darkness? (see attached pdf.)
Animal Structures and Function: A cube of sugar will not ignite from a lit match. Do
you think the cube will ignite if you sprinkle ashes on it first? This example could be
used to teach about catalysts and their functions in biochemical systems.
http://go.hrw.com/resources/go_sc/gen/HSTPR060.PDF
Evolution. Use bat YouTube clip and ask how bats navigate - bats are able to
negotiate obstacles without the use of eyes.
https://portal.utoronto.ca/webapps/portal/frameset.jsp?tab_tab_group_id=_2_1&u
rl=%2Fwebapps%2Fblackboard%2Fexecute%2Flauncher%3Ftype%3DCourse%26
id%3D_590052_1%26url%3D
Genetic processes. Use photographs of brown eyed and blue eyes individuals, and
family history and ask if two individuals with brown eyes and with forefathers with
brown eyes can become the parents of a child with blue eyes.
https://portal.utoronto.ca/webapps/portal/frameset.jsp?tab_tab_group_id=_2_1&u
rl=%2Fwebapps%2Fblackboard%2Fexecute%2Flauncher%3Ftype%3DCourse%26
id%3D_590052_1%26url%3D
Diversity of Living Things. Fish or Mammal? Ask students to categorise using
pictures of marine animals (sharks, whales, dolphins etc.).
https://portal.utoronto.ca/webapps/portal/frameset.jsp?tab_tab_group_id=_2_1&u
rl=%2Fwebapps%2Fblackboard%2Fexecute%2Flauncher%3Ftype%3DCourse%26
id%3D_590052_1%26url%3D
Hi there,
I've listed the 5 units in Grade 11U chem and an expectation beside it that the
discrepant event may be linked to. The site I found has a number of demos, and
some of which serve as good discrepant events.
http://www.nipissingu.ca/education/geraldl/sciencegeneral/discrepant_events.ht
m
1. Matter: Investigating properties of elements and compounds:
"Metals in your food!" Students may not realize there are trace amounts of metal,
ie:iron, in their breakfast cereal. Many breakfast cereals contain trace amounts of
iron in its elemental form. Flakes of these cereals can be floated on water in a petri
dish on the overhead projector and moved about by a strong magnet.
2. Reactions: investigate different types of reactions
"Water to Wine to Milk". Four glasses containing 4 different clear colourless liquids
(in order: acid, water + indicator, base, silver or lead nitrate) are at the front of the
class. One glass is continually poured into the other. A pink liquid is formed with the
first mixture, a clear colourless liquid is formed with the second mixture and finally
a white precipitate is formed in the last mixture. Students don't anticipate any
colour or precipitate changes as all liquids look like water.
3. Quantities: investigate quantitative relationships in chemical reactions.
"Disappearing liquids": Measure a set amount of alcohol and water. Mix them
together and the volume gets smaller! (Would also be good for the solutions unit)
4. Solutions and solubilities: investigating qualitative and quantitative properties of
solutions.
Students may forget to what extent milk is not a solution but a colloid. food
colouring and a drop of detergent is placed in a pan of milk. The hydrophobic ends
of the detergent molecules try to surround the fat globules in the milk, causing
movement of the milk at the molecular level this re-orientation of the different
phases of the milk cause the swirling effect we notice when the colours in the milk
begin to mix.
5. Gases: investigate gas laws that explain behaviour of gases.
"Collapsing can". Students don't expect gas laws to be demonstrated with changes of
temperature in open containers. The collapsing can shows this to be true: Boiling
water inside the can filled the can with water vapour which was cooled suddenly
when inverted into cooler water. Cooling the can caused water vapour in the can to
condense, creating a vacuum and causing the pressure outside the can to be greater
then inside and therefore crush the can.