ingridscience

Plant vessels in flowers visualized

Summary
Leave a white flower in food dye to colour the vessels up the stem to the petals. (Or just use a petal.) The dye traces out the xylem vessels in the stem and branching vessels in the petals of the flower.
Science topic (2005 curriculum connection)
Life Science: Needs of Living Things (grade 1)
Life Science: Plant Growth and Changes (grade 3)
Materials

For a whole flower:

  • white carnation
  • food dye (darker colours work better)
  • narrow tube to hold a carnation
  • tray to hold tube

For a petal:

  • white petal - a carnation works well
  • tape
  • letter sheet of white paper and two books about 1/2 cm thick
  • wax paper
  • food colouring
Procedure

Using a cut flower:
Cut the stem of a white carnation (or other white flower).
Stand the flower in a tube of food colouring for an hour or more (test to check).
Watch for the petals turning the colour of the food dye.
Cut the stem after colouring (to remove mess).

Using one petal:
(See attached booklet used at the NY Hall of Science museum.)
Cut the pointed end off a white petal. Stick the petal on a piece of tape, with the cut side hanging over the edge. Make sure the petal is lying flat on the tape.
Fold the paper lengthwise and bridge across two thin books, so there is a small gap underneath the strip of paper. Arrange so that the fold of paper is the low point.
Stick the petal to the white paper, so that it hangs off the bottom of the fold of the paper, with its cut side just touching the table.
Put a piece of wax paper on the table, in front of the petal, then drip a drop of food color onto the wax paper.
Slide the wax paper under the petal, so that its cut tip dips into the food color.
Watch for several minutes to see the food color creeping up into the petal. It traces out the vessels in the petal, which carry food molecules to all parts of the petal. The vessels extend down the stem of a flower, allowing transport of water and nutrients throughout the plant.
Unfold the paper and put another piece of tape over the rest of the petal, to stop the food color from making a mess.

Sometimes these branching patterns can be seen naturally in flowers. (see purple petunia photo)

Notes

Make a worksheet that has a box to put the petal in, instructions on how to face the petal, and other material.

Whole plant K-4 at AMNH, Gordon Science Club and NY city afterschool. Just petal all ages at NH Hall of Science.

Grades taught
Gr K
Gr 1
Gr 2
Gr 3
Gr 4
Gr 5
Gr 6
Gr 7

Forensic science

Summary
Try different methods of forensic analysis.
Curriculum connection (2005 science topic)
Life Science: Human Body (grade 5)
Physical Science: Chemistry (grade 7)
Procedure

Forensics is the collection and analysis of evidence from the scene of a crime, and includes fingerprints, blood analysis, DNA analysis, document analysis and trace evidence (hair, fibres, paint, glass etc).

Do the activities in any order, to understand some of these methods.

Notes

Include chromatography of a black pen, as an example of document analysis. e.g. bank robber hold up note.

School at Columbia did fingerprinting and invisible ink (though this is more of a spy activity).
isas did fingerprinting, hair and trace evidence, then ended with DNA.

Grades taught
Gr K
Gr 3
Gr 4
Gr 5

Invisible ink

Summary
Write a note in (nearly) invisible ink
Science topic (2005 curriculum connection)
Physical Science: Chemistry (grade 7)
Materials
  • saturated baking soda solution in a tub
  • Q-tips
  • card to write note on
  • grape juice in a tub
  • paintbrush
Procedure

Write your note in baking soda solution.
Allow to dry.
The note will be barely visible (though not invisible).

Paint grape juice over the note to make it visible.
(The grape juice turns a different colour when covering the basic baking soda solution).

Notes

Other ideas for invisible ink:
lemon juice invisible until heated
Ex-Lax tablets in water (contain phenopthalein) to write. Add baking soda solution to visualize.

Grades taught
Gr K
Gr 3
Gr 4

Fingerprinting

Summary
Take your own fingerprints and identify the patterns in them.
Science topic (2005 curriculum connection)
Life Science: Animal Growth and Changes (grade 2)
Life Science: Human Body (grade 5)
Materials
  • soft pencil
  • plain paper
  • clear tape
  • magnifier
  • fingerprint identification sheets (see suggestions below)
  • fine-tipped sharpie
Procedure

On the blank paper, ask students to draw around their hand(s). They will add a fingerprint to each of their fingers.

Use the pencil to scribble a dark patch on the corner of the paper.
Rub a finger tip in the pencil patch, pressing it down and rolling it around to make sure the entire finger tip gets coated in graphite.
Stick a piece of tape on the darkened finger tip, then peel it off. Stick the tape on the card over the appropriate finger tip.

Use an identification sheet to first determine whether each of the fingers have loops, arches or whorls. You may also find more complex patterns such as double loops or other combinations. This pattern is caused by ridges of skin. They stay in this pattern throughout your life, and even if you damage your finger they will grow back in the same pattern. Everyone, even identical twins, has a unique collection of fingerprint patterns.

Then look for minutiae - the places where the ridges start and stop and fork and merge. Challenge students to find a bifurcation, lake or hook.
Ask them to work with the magnifier and a fine-tipped sharpie to circle the minutiae that they find, just as a forensic scientist does.

Try these websites for images of fingerprint patterns and minutiae (or google search for "fingerprint patterns" or "fingerprint minutiae"):
http://www.forensicsciencesimplified.org/prints/principles.html
https://www.ijser.org/paper/Fingerprint-Minutiae-Extraction-and-Orienta…
https://globalwrong.files.wordpress.com/2012/02/galton-characteristics1…

Grades taught
Gr K
Gr 1
Gr 3
Gr 4
Gr 5

Nutrients in animal feed

Summary
Match animal feed (e.g. horse) with the nutrition they provide
Science topic (2005 curriculum connection)
Life Science: Needs of Living Things (grade 1)
Life Science: Animal Growth and Changes (grade 2)
Materials
    Dishes of dried horse foods, labelled with their name and the nutrition they are rich in:
  • 1. Fresco. Lots of vitamins.
  • 2. Alfalfa and hay. Lots of fibre.
  • 3. Performance pellets. Lots of protein.
  • 4. Rice bran. Lots of fat.
  • Images of human foods:

  • 1. fruits and vegetables [vitamins]
  • 2. bread and pasta [fibre]
  • 3. milk and eggs [protein]
  • 4. vegetable oil [fat]
Procedure

Find the horse foods on the table.
Notice that they each provide different nutrients: fibre, protein, fat and vitamins
We need the same nutrients.
Match each human food with the horse food that provides the same nutrition.

Grades taught
Gr 1
Gr 2

Pumpkins

Summary
Look inside a pumpkin, find out what the seeds are for, and look at other familiar foods with seeds.
Curriculum connection (2005 science topic)
Life Science: Characteristics of Living Things (grade K)
Life Science: Needs of Living Things (grade 1)
Life Science: Plant Growth and Changes (grade 3)
Materials
  • pumpkin pre-sliced into segments, one for each student
  • large (petri) dish for each pumpkin slice
  • pea seeds, or other large seeds (pumpkin ideal)
  • germinated (pea) seeds, germinated pumpkin seed ideal
  • (pea) seedling, after a week of growth in a pot of dirt (pumpkin seedling ideal)
  • familiar fruits (tomato, pepper) and other vegetables that are not fruits
Procedure

What’s inside a pumpkin?
Give each student a slice of pumpkin/whole pumpkin on a dish.

What do you see? Draw on board as students name things. Look very closely - see stuff you have never seen before. (e.g. seeds, pulp, thready stuff around seeds, rind.)

Pull out the seeds. Count them. How many seeds in the whole pumpkin?
Add each students count to a board, then do the approx math for how many in the whole pumpkin
Lot of seeds. What are they for?

What do the seeds do?
Make new pumpkin plants. How do they do that?
Show pea seeds - seeds split open, grow a root and a shoot.
Pull up seed in pot to show roots and shoot and seed.
A plant makes a fruit, so that it can make more seeds, so that it can make a new plant: life cycle. Show pumpkin life cycle images, and relate to their worksheet.
Not all pumpkin seeds grow, so they make in a lot.
(If time and head space, back to structure: seeds make a new plant, rind protects it from rotting, pulp attracts animals that eat the seeds and spread them around).

What other things are fruits?
Pumpkin is a fruit - it has seeds.
What else is a fruit? Is this? (tomato, pepper, lettuce, celery) Show the rest of the plant each time.
When you eat plants at home, you can tell your parents which parts of the plant they come from.

Notes

This is a half hour lesson

Grades taught
Gr K

Food web model

Summary
Students build a food web by connecting different living things with wool. This activity shows a temperate rainforest food web.
Science topic (2005 curriculum connection)
Life Science: Needs of Living Things (grade 1)
Life Science: Habitats and Communities (grade 4)
Life Science: Diversity of Life (grade 6)
Life Science: Ecosystems (grade 7)
Materials
  • cards with silhouettes of living things on them - see photo for temperate rainforest ideas
  • ball of yarn
  • duct tape
  • floor space that fits the students in a circle
Procedure

Sitting in a circle version:
Sit at the carpet in a circle. (Standing can work too for older students.)
Hand each student a card with a living thing on it. Students hang it around their neck to display their living thing for everyone to see. Each student tells the class what living thing they are.
Hand a ball of yarn to a student who has a plant on their label. Tape the end of the yarn to the carpet securely with duct tape in front of them.
After class discussion, pass the yarn ball to a student that has a living thing that would eat the plant. Make a line of wool stretching between them, then tape the yarn strand to the floor in front of the new living thing.
Continue, connecting more living things together.
Once you get to the top of the food chain (top predator like cougar), it can be connected to a living thing that might grow out of its body after it dies e.g. mushrooms. Or, after a top predator, you can also move back down the food chain to something that is eaten by the predator. The order does not really matter, but just connect all the living things to something else by who eats who.
To help determine who has not yet been included in the food chain, students can remove their card from around their neck and place it on their tape piece on the floor in front of them.
A criss-crossing web of connections is made, forming a 'Food web'. (A food web is many connected food chains.)
Depending on the age of the students and how long they can sit, living things can be linked many times.
For younger students, include each student once, then discuss how there are many more connections.
This activity is similar to: https://betterlesson.com/lesson/640194/the-food-web (see the Explore/Explain section). This lesson also includes the sun and talks about transfer of energy through the food chains.

Tabletop version:
Give student groups a stack of index cards with a living thing named on each.
Students lay the cards on a table, then use lengths of wool to connect the living things that eat each other.
Students could add their own living things to their food web.
Compare the food webs that each group made.

As a class, discuss how complicated a food web is, and how living things depend on each other. If one living thing is removed, through habitat change or human interference, other living things are affected.

Grades taught
Gr 1
Gr 2
Gr 3
Gr 4

Animal dung study

Summary
Look closely at animal dung (e.g. horse), to see what is in it, and how it compares to what the animals eat. Discuss what animals might eat dung.
Science topic (2005 curriculum connection)
Life Science: Needs of Living Things (grade 1)
Life Science: Animal Growth and Changes (grade 2)
Life Science: Habitats and Communities (grade 4)
Life Science: Ecosystems (grade 7)
Materials
  • dried [horse] dung in petri dishes
  • whole piece of [horse] dung
  • magnifiers
Procedure

What is this? Look at it with your magnifiers. (don't tell students what it is until they have looked at it and identified grass/seeds etc in it first).
Animal dung! Here is one whole piece of dung. You each have part of one of these.

All animals make waste, once they have extracted as much nutrition from their food as they can.

Use magnifiers to see what is in in dung. Here is the food they eat. How does it compare?

The [horse] does not digest much of the plants they eat. Plants are hard to digest. There is a lot of nutrition left in [horse] dung. So much that it is food for another animal.
What animals might use the nutrition in [horse] dung?
Worms, wood bugs (they eat rotting plants), birds (they eat seeds).

Grades taught
Gr 1
Gr 2

Animal dung and the food web

Summary
Starting with animal dung/horse manure discuss the animals and plants that are connected to these animals, then build a food web.
Curriculum connection (2005 science topic)
Life Science: Needs of Living Things (grade 1)
Life Science: Animal Growth and Changes (grade 2)
Life Science: Habitats and Communities (grade 4)
Life Science: Ecosystems (grade 7)
Materials
  • board to draw food web on
Procedure

Today we’ll look at food webs: how [horses] are connected to other animals.

Horse dung study
Add the animals that eat [horses] dung (e.g wood bugs, worms) to a food web diagram.

What happens when these animals eat the half rotten plants?
Observe a worm closely to see the dirt in the gut.
These animals turn rotting plants into dirt. Worm poop is dirt.

What grows in dirt? Plants! Add arrow to food web.
The decomposers are a critical part of the food web.
They eat living things and break them apart to put the nutrients back into the soil.

Food web game to show the interconnectedness of [horses] and other living things.

Notes

This is a half hour lesson

Grades taught
Gr 1
Gr 2

Teeth in herbivores, carnivores and us

Summary
Compare teeth from herbivores and carnivores, using real jaws if possible. Or just use the jaw of one kind of animal, as part of another lesson.
Science topic (2005 curriculum connection)
Life Science: Characteristics of Living Things (grade K)
Life Science: Needs of Living Things (grade 1)
Life Science: Animal Growth and Changes (grade 2)
Life Science: Human Body (grade 5)
Life Science: Diversity of Life (grade 6)
Materials
  • optional: mirror (see notes)
  • animal jaws if possible
  • illustrations of different categories of teeth
Procedure

An animal's teeth is an adaptation for the food that it eats.

If herbivore jaws are available:
Look at the herbivore jaw bones and teeth. (Photos show lower jaws of herbivores.)
Herbivores have teeth that are adapted to smash up plants. Their incisors at the front of the jaw snip off the plant stems and leaves (these are often missing from a found jaw; only present in the sheep jaw in the photos). To grind the plants they use their molars, which have sharp ridges on the top and fit together perfectly to smash the plant cells open.
3D view of positioning teeth in a mouse jaw: https://www.youtube.com/watch?v=oLn70NiouS4

With a skull and associated jaws:
Insert the jaw bones in the skull and show how tightly the teeth fit together. Show how the jaw moves sideways to mash plants between the teeth.

If carnivore jaws are available:
Carnivores need sharp teeth to catch prey and rip meat. Canines are huge, and even on domestic animals they can be terrifying (show cat and dog photo). Incisors are tiny. The molars are sharp to shred meat.
Look at real carnivore skull to see teeth (e.g. I have cat skull with upper jaw including canines)

Look at human teeth:
We are omnivores - are jaws and teeth are adapted to eat both meat and plants.
Students use a mirror to find the different kinds of teeth in their mouth: incisors, canines, molars (use illustrations to show the different types)
Canines are there but small - between the two.
Incisors are more like herbivores though no where near as big.
Molars are between the two.
We are omnivores. (Same as bears and racoons.)

Notes

Students are distracted from the task at hand (looking at their teeth) with the mirror. Try looking in partner’s mouth for different kinds of teeth.

The students were very interested in the different herbivore jaws.

Grades taught
Gr 1
Gr 2
Gr 3
Gr 4
Gr 5
Gr 6