Introduction to the periodic table, home learning

Introduction to the periodic table, home learning

All you need to know about the periodic table and atoms 1

Elements sit on the periodic table so that atoms with similar properties lie in the same column

Work through The Introduction to the Periodic Table Prezi then do the quiz to check your understanding.

By the end of this unit you should know:


  • what the atomic number and mass number of an element is.

  • how elements are arranged on the periodic table.

  • what Periods and Groups are.

  • the physical and chemical properties of the group 1 metals.

  • the physical properties of group 17 elements.

  • the physical properties of group 18 elements

  • that sodium and chlorine react violently together.

  • that elements in the same group have similar properties. WHY!

The Secret Life of Potatoes

The Secret Life of Potatoes

Tales From a Tiny Garden

The Secret life of Potatoes











Deep underground in a potato tub in a tiny garden near Lake Rotorua.

 A lonely potato continues its cycle. Dug up and replanted twice to investigate what happens out of sight in the dark wet soil. Late in the season it’s leaves are attacked by a plague of leaf chomping potato moth caterpillars.

Growth is powered initially by the tuber near the bottom of the tub. When leaf development is sufficient, excess sugars from photosynthesis are passed down the stem and stored in growing stolons as starch. Have a look.

Attack of the killer wasps

Attack of the killer wasps

Tales From a Tiny Garden

Attack of the killer wasps















Chemical warfare in a tiny garden in Rotorua sitting above the lake not far from the CBD.

Chemical warfare in a tiny garden in Rotorua.

A sunny afternoon relaxing in suburban Rotorua, above the lake not far from the CBD. Bad things happen in tiny gardens.

Early summer and dark chemical processes are at work in the bright sunlight. Swan plants are producing and stockpiling deadly molecules in their sap and leaves. A chemical defence system designed to kill insects foraging for food.  The main components of this molecular arsenal are cardenolide glycosides, steroids with an attached sugar structure. These toxins can induce cardiac arrest.

Monarch caterpillars and butterflies are immune to these poisons. Caterpillars voraciously devour swan plant leaves. In the process they hijack the plant’s chemical defence system for use against predators. Birds associate becoming sick with a diet of brightly coloured caterpillars or butterflies and drop them from their diet.


Attack of the killer wasps.

Asian paper wasps are very determined predators of monarch caterpillars and are unaffected by the cardenolides. Wasps need protein for nest construction and developing larvae in spring and early summer. Caterpillars are a good source of protein at this stage.  

I watched wasps make their way through dense foliage in relentless pursuit of their prey. Monarch caterpillars appear to understand the danger and some seek refuge amongst the spines of the swan plant seed pods. The aerial bombardment is relentless and a plant can be completely stripped of the caterpillar population in a day. The big mature caterpillars are a favourite target and I have seen them stand up on a leaf in a forlorn attempt to beat off a merciless attacker.

The assault has a number of stages

  • The wasp lands on the caterpillar and probably stings it
  • The wasp starts to skin the caterpillar while it is still moving. It bites through the skin which rolls back to reveal the underlying body.
  • It may move the whole carcass to a more stable location where it slices it up into manageable chunks to fly away with.

In late summer when the need for protein has diminished, wasps change their diet, feasting instead on the nectar produced by swan plant flowers.

Relationship beteeen steroids and cardenolide glycosides

oleandrin a cardenolide glycoside

oleandrin a cardenolide glycoside

 Oleandrin is one of the cardenolide glycosicdes found in swan plants. The structure hanging on to the bottom left of the steroid skeleton is based on a sugar unit hence the glycoside in the name.

Attack of the killer Mantis

Attack of the killer Mantis

Tales From a Tiny Garden

Attack of the killer Mantis












A sunny afternoon relaxing in suburban Rotorua. Owhata, above the lake not far from the CBD. Bad things happen in tiny gardens.

A sunny afternoon, the perfect picture, where’s my camera when I need it? A white butterfly flutters gently on a pot plant decorating the fence line beside the tree nursery. It is rushing to fill the the tank with carb rich nectar. It’s dangerous to park here for too long. Something is amiss? The delicate wings are beating with too much urgency. Maybe two insects are locked in an embrace, rolling on the soft red petals. I need a closer look or perhaps a visit to Specsavers.

My tiny garden is a beautiful savage microcosm.The terrified butterfly is held in the death grip of a Praying Mantis. Two raptor arms encircle wings and abdomen. Pointy restraining  attachments on the legs gouge the insect’s abdomen as it struggles to escape. Sharp teeth slice effortlessly through brain and neck ending the brief resistance.

After five minutes of carnage all that remains of the butterfly is a single surgically amputated winglet that escaped  butchery, floating away on the gentle breeze.

The video was taken using a Canon EOS 60D camera. Invidual clips were editied together using Gopro Studio.

For further horrors in a savage garden: Attack of the Killer Wasps  and Attack of the Killer Ladybirds

The Hibiscus Flower Night Show

The Hibiscus Flower Night Show

Tales From a Tiny Garden

The Hibiscus Flower Night Show

I used a Picamera attached to a Raspberry Pi 3 running a simple time lapse code. The 5 megapixel camera shot one frame every 120 seconds. The final movie was processed using Time Lapse Tool at 30 frames per second,

The plant was illuminated at night with a 12v AC PRO Jumpstarter  equiped with an emergency light

Hibiscus flowers are brightly coloured plate sized beacons. They evolved to attract humming birds and winged insects. They open at night and are ready for action when the sun comes up. Nothing much happens as the bud prepares to open during the day. The nocturnal opening is explosive.


The brightly coloured bulls-eye guides hummingbirds and butterflys into the flower.

The large erect central stamen has anthers anthers loaded with yellow pollen.

five dark stigmas collect pollen pushed onto them by flapping wings.

The flower is capable of collecting large volumes of water and sunlight on it’s surface.

I wonder.

What triggers the flower opening?

What drives the flower opening?

Slow opening flowers have a longer existence than fast opening flowers, why?

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