|
1999-00 -- 05-06 Academic Years Botany |
14 September 1999: Chuck Buzek (Spry School)
took us out to the IIT meadow and led a discussion on the
feasibility of science fair experiments involving biology. Digging
down through soil might reveal different organisms at different depths.
Trees may tend to grow more in one direction than another. How
could we find out? Chuck gave us some ways to learn how. Great!
12 October 1999: John Scavo [Richards Voc HS]
26 October 1999: Glenda Ellis (Williams School)
handed out rulers (metric), a Data & Observations page, and we
each got several maple leaves. She had us measure and record (in
cm) from the tip of each leaf to the bottom of its stem
(Length, and then by having us raise our hands, she
determined how many leaves had lengths of 7.0 cm, 7.5 cm,
etc. up to about 13.0 cm. Using this data, a graph of the
number of leaves (vertical axis) of a given length
(horizontal axis) could be plotted, showing variation
in leaf length. What an interesting idea! ...and such a
good way to get students involved in observation,
measurement, graphing, and possible interpretations!
02 May 2000: Chuck Buzek (Spry School)
took us outside to
"measure" tree heights and canopy widths (related in most
cases). The nice weather made this a pleasant thing do,
and we gained some insight into the characteristics of
trees and how they may be measured. A fine way to end our
last meeting for this semester!
09 October 2001:
Barbara Pawela (May School, retired)
Barbara showed some plants just taken from her yard [or
"garden", if you speak British], as well as those obtained
elsewhere We investigated the structure, life cycle, and process
of reproduction for the following plants:
To complement the discussion of the specimens, Barbara distributed a handout, What Do Root Hairs Look Like?
Barbara also handed out bean seeds to be grown in the zip-lock bags. The marigold and pumpkin seeds should be placed in potting soil to make the plants. We will wait and watch for them to grow!
23 October 2001:
Carolyn McGee and Carolyn McBride (Manierre School)
were the dynamic duo who used a variety of different-sized pumpkins to
illustrate nutrition facts about pumpkins and other fruits and
vegetables. They passed out activity sheets that guided
investigation of different pumpkins. We were given plastic
gloves, and we cut the pumpkins in order to see how many seeds there
were, and what kinds, in different pumpkins. There are hundreds
of websites concerning pumpkins; for example, see
http://www.urbanext.uiuc.edu/pumpkins/nutrition.html and http://www.pumpkinnook.com/facts/nutrition.htm.
In cutting the pumpkins open and counting the seeds, we notice that the seeds are arranged inside the pumpkin in an organized manner, which probably reflects the structure of the ovary of the female flowers. Here are the numbers for pumpkin seeds:
| Tiny Pumpkin | 100 seeds |
| Medium Pumpkin | 350 seeds |
| Medium Pumpkin | 405 seeds |
| Large Pumpkin | 510 seeds |
19 February 2002:
Fred Schaal (Lane HS Math -- Visitor)
Fred explained that he often picks up fallen
branches that happen to have buds on them, brings them home, puts them
with water
in a vase, and waits for the bulbs to open within a few days. He
has had
trouble in making this work the last few times, and asked whether
anybody knew
of a "trick substance" to add to the water to improve the likelihood
of success. Any suggestions? We then had an extensive
discussion as to the best way to get an Amaryllis Bulb to sprout inside
the house in
winter.
Good, Fred!
Note added by PJ: The following information is an excerpt from the website The Joys of an Herb Garden: http://www.orchardsedge.com/articles/herb.jsp:
... "In winter, indoor space is used to start new seedlings or cuttings to be placed outside in the spring, using natural sunlight to ripen the plants. This routine will provide at least 3 outdoor/greenhouse harvests per year. If more space is available to constantly be starting indoors and flowering 2nd harvest plants outdoors, harvests are possible every 60 days in many areas, with a small indoor harvest in the winter as a possibility as well.
The basic strategy of year round production is to understand the plant has two growth cycles. At germination the plant enters into a vegetative state and will be able to use all the continuous light you can give it. This means there is no dark cycle required. The plant will [... photosynthesize ...] constantly and grow faster than it would outdoors with long evenings. Photosynthesis stops during dark periods and the plant uses sugars produced to build during the evening. This is not a requirement and the plant will grow faster at this stage with continuous photosynthesis (constant light)." ...
That website contains quite detailed information of relevance. For sprouting Amaryllis Africanus bulbs, check out WINTERTIME BULB TALK: http://www.dutchbulbs.com/bulbs/ or Forcing Bulbs for Early Winter Cheer: http://www.johannsens.com/newsletters/page3fall97.html.
23 April 2002:
Barbara Pawela (retired and happily active) -- Spring Planting
Barbara showed her tomato plants that sprouted from seeds
2½ weeks ago
-- which are 2 -3 cm tall -- most with just 2 leaves, which
are called cotyledons.
For further information on nurturing and growing tomato plants, see the
Tomatosphere
Tips website: http://www.tomatosphere.org.
Barb then put two clear plastic cups [about 250 ml] on the table. One of them was filled with potting soil, and the other was filled with "Schultz Seed Starter", which contains vermiculite [soil conditioner] and other materials. For more details concerning this material, see the Schultz Company website http://www.schultz.com/, and the particular description of this material: http://www.schultz.com/ProductCategories/Soilsamendments/SeedStarter/.
We examined each cup for porosity of material, and added the same fixed volume of water to each one. The potting soil was able to absorb water more readily. The seed starter will keep things a little more dry around germinating seeds, and helps prevent rotting of new seedlings, a problem that is very common in an overly moist environment.
Barb then had us start bean seedlings by placing the beans onto dampened paper towels, which we then sealed in zip-lock bags. We next planted cantaloupe and watermelon seedlings in pots. Now we are ready for Spring to come, thanks to Barbara!
08 October 2002:
Teri Roland [Joliet West HS] Why
Leaves Change Color [
http://www.na.fs.fed.us/spfo/pubs/misc/leaves/leaves.htm]
Teri first asked us for an explanation, and after rejecting
several
suggestions --- such as that the trees were blushing because they were
losing their
"clothes" --- she explained that the fall colors result from chemical
compounds that
have been in the leaves all summer, but have been "drowned out"
by a much
higher concentration of green chlorophyll. When winter approaches, it
is a signal
(not fully understood but probably triggered by fewer hours of
sunlight) to the
(deciduous) tree to shut down chlorophyll production and prepare for
its winter
"nap". Teri started by putting spinach leaves in a blender,
adding some acetone (nail polish remover) and "pureeing" to get a dark
green
solution. We then put a small drop on a long strip of chromatography
paper (other
paper can also be used, e.g. coffee filters, regular filter paper,
certain paper
towels, ... ) and inserted it into test tubes containing a solvent (90%
petroleum ether
and 10 % acetone) which Teri had developed by
experimenting with different
mixtures. In a short time the colored pigments started moving up the
paper (by capillary action) and we clearly saw a separation of colors
with green
moving faster and yellow following up behind. The separation occurs
because the
molecules making up the various pigments have different attractions for
the
paper; the ones more strongly attracted moving more slowly. By
comparing the
behavior of a sample with known compounds, it is possible to rule out
certain
compounds because of different rates of movement. Teri also
showed us
a faster way to prepare the chromatographic strips, which would be
especially useful
for comparing leaves from several different trees . The leaf is placed
on the
paper, and the edge of a coin is pressed against the outer surface
firmly enough
to make a "grass stain" on the paper. Then proceed as before. What a
good
fall project with a lot science in it for further investigation! [Many
plants
will show more than one green pigment, indicating that there are
different types
of chlorophyll present.]
Thanks, Teri!!
22 October 2002: Christine Scott [Beethoven Elementary
School] and Lilla Green [Hartigan Elementary School,
retired] Handout:
A Twig's Story
Christine and Lilla distributed the handout, showed and
discussed twigs,
and passed out twigs for examination. We studied the twigs
to
identify scars from which leaves grow in the spring. The number
of
terminal bud scars shows the age of the branch, in years.
Terminal buds
are located where new growth will occur, and lateral buds for sideways
growth.
This growth can yield new branches or new roots, depending on the
environment of
the bud. Features of twigs, such as the shape of the leaf scars
and the
number of terminal buds at the tip of the twig (for twigs that come
from the end
of a branch) can be used to identify the species from which the twig
came.
The twig article is found in the book The budding botanist: investigations with plants, AIMS activities. [http://www.aimsedu.org AIMS Education Foundation 1993] ISBN 1-881431-40-1:
Abstract: "Activities Integrating Mathematics and Science (AIMS) books primarily integrate mathematics and science but also provide coordinating activities related to other curriculum areas including language arts, social studies, physical education, art, and music from grades K to 9. This activity book is designed for students in grades 3 to 6. The book's objective is to foster students' interest in plants by teaching introductory knowledge of seed plants, their structures, and their economic importance. Particular attention is given to seeds (their structure, how they grow, their properties, and how they are dispersed); plants (their structure, how plant parts work, photosynthesis, and development of seed and fruit); and a short look at the structure of the plant cells. The activities generally include an introductory statement, math skills, science processes, materials, key questions, classroom management suggestions, procedures, discussion questions, extensions, curriculum correlations with other disciplines, and illustrated student worksheets. The book includes a table of contents, a glossary, and a list of the intended mathematics and science process skills."Great Lesson, Christine and Lilla!
Contents: Conceptual overview; Letter to parents; Why are plants important?; Enviroscape; Seed facts; Seed search; Dissect a seed; Seed scavenger hunt; Germination study; Test a seed; Exploring germination; Comparing germination; Seed plants; Cones and needles; History of a tree; Observe a tree; A flower study; Seeds from fruits; Plant structure facts; Down under; Herb and woody; A twig's story; Leaf facts; Leaves; Leaf printing; Photosynthesis; Transpiration; Cactus; New plant discovery; Cell facts; Model of a cell; Focus on cells; Cell your fruits and vegetables; Glossary; Literature list. Source: http://www.enc.org/resources/records/full/0,1240,000027,00.shtm.
22 October 2002:
Chris Etapa [Gunsaulus Academy] Observations
and Categorization.
Chris showed three jars of sunflower seeds and described a class
activity of
"observations". The idea was to describe the different,
individual sunflower seeds as objects. One might use such phrases as
oval
shaped, black and white, color, pattern, size, shape, texture,
and number and arrangement of stripes. We decided that "stripes"
provided the best method
of categorization of our seeds. One could use the descriptions
given in
one class to see if another class could pick out the individual seeds
from the
description. Results are often inconclusive because descriptions
are not
sufficiently different. Such an activity is a convenient way, at
the beginning of the
school year, to hone observational skills and focus on the need for
precision
and attention to detail in recording data of all kinds. Good
idea, Chris.
11 February 2003:
Fred Schaal [Lane Tech HS, Physics] Tree
Circumferences
Fred described measuring the circumference c (in inches)
of a tree
(with roughly
circular cross section) in order to determine its diameter d (in
inches), by dividing by
p » 22/7 (or, better yet,
p » 355/113):
25 March 2003:
Ana Timbers [Haven Middle School,
Evanston]
Starch in Green Leaves
Ana had a beautiful, large, hand-lettered and hand-drawn poster,
which she
posted on the blackboard in the front of the class, to help us follow
these instructions:
Why does the iodine produce the color change in the leaf? [Actually, it was too difficult to see any color change because the iodine solution too concentrated and would cause a dark stain, even with out starch present.. Therese suggested diluting the iodine solution with isopropyl alcohol. Then the iodine had a golden color --- easily distinguishable by that black color made in the presence of starch.] We concluded that the iodine had reacted with the starch in the leaf, which remained there even though the chlorophyll had been removed previously. To demonstrate the starch reaction more vividly, Marva Anyanwu suggested we put iodine on a piece of bread --- and that turned out to produce a very striking color change.
We experienced the Biology of everyday life! Thanks, Ana!
25 March 2003:
Brenda Daniel [Fuller Elementary School] and Erma Lee [Williams
Elementary
School] Different Salads in a Bowl
Erma and Brenda made a salad consisting of various mystery
ingredients,
which we identified and categorized according to the organism, and part
of
organism, that was the source of each:
| Ingredient | Source |
| Crackers | Flour, Oil (from seeds) |
| Broccoli | Flower; stem |
| Carrots | Root |
| Onion | Bulb |
| Cucumber | Fruit |
| Tomato | Fruit |
| Mayonnaise | Eggs (from animals), oil (from seeds) |
| Shrimp, chicken | Animal muscle |
| Drinks | High fructose corn syrup (from corn kernels; i.e., seeds) |
08 April 2003:
Brenda Daniel [Fuller Elementary School] and Erma Lee [Williams
Elementary
School] Edible Plant Parts
Erma and Brenda followed up their presentation at the previous
meeting by
handing out this List of edible plants (roots, seeds, fruits, leaves,
and pods):
| Roots | Seeds | Fruits | Leaves | Pods | |
| beets | beans | apples | apricots | basil | chili peppers |
| carrots | peas | artichokes | avocados | Brussel sprouts | green beans |
| Jerusalem artichokes | pumpkin seeds | bananas | bell peppers | beet greens | okra |
| leeks | sunflower seeds | berries | cranberries | cabbages | sugar snap-snow peas |
| onions | cucumbers | dates | chard | wax beans | |
| parsnips | eggplant | figs | cilantro | ||
| potatoes | grapefruit | kiwi | endive | ||
| radishes | kumquat | lemons | kale | ||
| rutabagas | mangos | melons | lettuces | ||
| scallions | oranges | papayas | mustard greens | ||
| sweet potatoes | peaches | pears | parsley | ||
| turnips | persimmons | pineapple | spinach | ||
| yams | plums | pomegranate | turnip greens | ||
| pumpkin | strawberries | watercress | |||
| squash | tangelos | ||||
| tangerines | tomatoes | ||||
A deliciously interesting lesson, Brenda and Erma!
22 April 2003:
Jyotiben Desai [Du Sable HS]
Mining for Peanuts [handout]
J Desai helped us celebrate Earth Day [22 April 2003 --
TODAY!] with her
activity. Each group put several glass marbles into a TV
dinner tray, and then covered
them with potting soil, raking the potting soil over the marbles so
that they could not be
seen. Each group also made a map of the locations of their marbles.
We then exchanged trays, and mined for marbles! for
about 5 minutes. We used small objects, such as paper
clips, Popsicle®
sticks, and coffee stirrers. as probes. Finally the trays
were
returned to the original group that planted them, who assessed
now much damage
was done to the soil surface by this mining operation.
It is a reminder that activities that provide benefit to society, such
as
digging marbles, can have undesirable, and often unanticipated,
side effects. Putting layers of soil, then sand, then soil over
the marbles
would be a more complicated, but perhaps better, model of mining, since
the
disturbance of the soil by our mining operations would have been much
more
visible and much more difficult to restore. Use of peanuts
instead
of marbles is another suggestion. The peanuts,
when found,
could be shelled, and the shells collected as a model of the waste (tailings,
slag, polluted water, particulates) produced
from mining operations.
A very good lesson on conservation. This lesson appears in the following book, (p 222):
Holt Environmental Science [1996: ISBN 0-03-003133-8]
Holt, Rinehart and Winston, Inc
1120 South Capital of Texas Highway
Austin, Texas 78746
Comment by PJ: The peanut plant, like the soybean, is a legume, which enriches the soil though nitrogen fixation. Farmers typically plant in rows, use a type of turning plow to turn over the edible subterranean nodules [often called goober peas in the 19th century, and referred to as peanuts today]. Some time later the rest of the plant is plowed into the ground to encourage aeration of the soil and composting of organic material. Legumes actually enrich the soil when cultivated in this way --- in contrast to potato farming, which removes vast amounts of nutrients with each crop.
Great job. Thanks, J!
22 April 2003:
Marva Anyanwu [Wendell Green School]
Potatoes on the Desk
Marva placed three potatoes on the desk, and asked what students
would say [or
think!] if they saw them on the teacher/s desk when they first came
into the
classroom. Various ideas were suggested. She then stated
that we
would use them to describe and visualize the process known as cloning.
When we cut out a little piece of potato containing an "eye", we might
expect to be able to grow a potato exactly like the old one, since the
DNA
should be identical to the original potato. However, we actually
would produce a new
plant, with an identifiably different potato (tubers). How
could that be?
Ben Stark [IIT]
then led a discussion of cloning, including a more extended
description of
cloning in plants, cloning in animals, and the famous cloned sheep, Dolly!
For
additional information on cloning, see,
for example Beyond Jurassic Park: Real Science with Ancient DNA
http://www.apsnet.org/education/feature/ancientdna/Top.htm: and
the Scientific
American News Scan feature: Ma's Eyes; Not her ways [April
2003]
http://www.sciam.com/article.cfm?colID=5&articleID=000DE213-6B0F-1E61-A98A809EC5880105.
Very nice, Marva!
07 October 2003:
Chris Etapa [Gunsaulas
Academy] Nature Walk, Part I
Chris took us outdoors on a stroll through the campus to collect
several
specimens of various types of leaves. We obtained simple leaves,
compound leaves, single leaves, and leaf bunches still on their
branches.
We will take these home, put them between layers of newspaper under
weight, and
press them. At the next class we will bring back the pressed
leaves, to
continue with Part II of this experiment.
What happens next time?? Very nice, Chris!
21 October 2003:
Chris Etapa [Gunsaulas
Academy] Nature Walk, Part II
We finished the class with a follow-up to the previous lesson [bc100703.html],
where we brought in a wide variety of autumn leaves. Chris
reviewed some of
the physical features of leaves used to identify them. Then she showed
us some
(fantastic) collages made by students in her science club using leaves
they
had brought to class, and she gave us 15 minutes to make a
collage with our leaves.
The collages used leaves of various shapes and sizes to make
exceptionally
creative images of animals: fish, an elephant, birds, etc.
We were expected
to identify as many tree species as possible, and to describe the
type of leaves
shown in our drawing. Glue was used to attach the flattened
leaves to a heavy
paper backing.
21 October 2003:
Earl Zwicker called attention to an article by David
Perlman in The San Francisco Chronicle:
BIZARRE BURROWING PURPLE FROG FOUND: Mysterious creature hails
from time of Gondwanaland
"...In the verdant countryside of western India along the Arabian Sea,
villagers digging a well in a cardamom plantation five years ago were
astonished to spot a squat, bulbous purple frog sitting immobile nearly
seven feet down in the mud. ... With a pointed snout, glistening deep
purple skin, red eyes and a powerful talent for burrowing into the
ground, it looked like something primitive. Indeed it was. The
family appears to date back more than 200 million years to a time when
Africa and India were joined in a single vast supercontinent now called
Gondwanaland. By 150 million years ago that continent had broken up
into chunks of land masses that included Madagascar, the Seychelles,
and the western Ghats of India.. ... " For more details see the
following website: http://snurl.com/2pgt
04 November 2003:
Wanda Pitts[Douglas
School] Leaf Art
Wanda provided follow-up to last week's "Leaf Art" activity by
showing us pictures made
by her students and asking us what they represented. In some
cases there was a consensus, in
others we came up with several different possibilities, and in a few
cases they were relegated
to "modern art". Thanks, Wanda.
04 May 2004:
Christine Scott [Beethoven Elementary
School]
Seeds
Christine brought in various plant parts containing seeds:
squash, orange, apple,
peanut, as well as assorted dried beans. She gave each of us a
baggy
containing various types of seeds, as well as a key made up as a
grid. We
tried to match each of our seeds with the entries on the
grid. Christine
then passed around a template, in which the seeds were taped onto the
appropriate location on the grid. Magnifying glasses were very
helpful in
identifying the smaller seeds. This was a fascinating
phenomenological
exercise, and we found it challenging to make an identification of a
particular
seed. One possible extension might be to obtain 10 seeds of the same
type, weigh
each of them and note the range in masses, and discuss why individual
seeds vary
considerably in size, strength of integument, etc.
Thanks for the ideas, Chris!
12 April 2005:
Chris Etapa [Gunsaulas
Academy] Greenhouses on
the
Go
This is another activity that is part of the greenhouse project that
Chris had talked about earlier in the year. Chris brought
potting soil, which we moistened and which we used to fill 1 quart
Ziploc™ bags. The soil was packed into the corners (to help the bag
stand up) up to near the top of the bag (but leaving enough room for
the bag to close). We
sprinkled about 5-
6 seeds (we used pickling cucumbers) on top and sealed the bag. Put in
a sunny window and let the seeds sprout until they are pushing against
the top of the bag. Then open the bags and let the plants grow further
until they can be transplanted. Each child's name and other information
can be easily recorded on the bag. This activity is appropriate for
many grade levels, with experiments (vary light, temperature, etc.)
added and discussions made more sophisticated as the grade level
increases.
This was a blast! Very good, Chris!
26 April 2005:
Ben Stark [IIT Biology]
Seeds of Wisdom
Ben brought in his "seed sprouter" from the last session --
for details see
Chris Etapa's presentation from the last SMILE meeting
bc041205.html.
It had been very successful, with
all planted seeds apparently sprouting. There were six healthy shoots,
some
nearly
20 cm long with first leaves. The zip-lock bag had been open for
about 10 days to
permit the shoots space to grow, but the soil was still fairly moist
below the surface --
although water had been added a few hours before.