We have been given such an EXTRAORDINARY sand sample from a beach in Okinawa archipelago in Japan. The grains of sand are shaped like tiny stars.

These are not really sand but the exoskeletons of tiny one-celled organisms called Foraminifera (foram for short) that live among the shallow sea grass.

The star-spines help them move from place to place and to capture and store tiny diatoms on which they feed

The locals have a different story. According to them, the star shells are the tiny offspring of the Southern Cross and the North Star.

These children of the stars were born in the ocean just of Okinawa, but were killed by a giant serpent. Their tiny skeletons are all that remains.

Star Sand

Baculogypsina sphaerulata

The star sand's test is made from calcium carbonate. This show it lives

in shallow water - calcium carbonate is quite soft. In deeper water a

test of softer calcium carbonate would crumble.

3-Star Sand 6.jpg

Other kinds of foraminifera are also in the sand. The shine indicates

that the test is made from strong, glassy silica because this foram lives

much deeper in the ocean where the pressure on its shell is greater.

1-Star Sand 3.jpg
Sorites Orbiculus

Calcarina gaudichaudii

Rheophax species?

Some forams build their shell by gluing together grains of sediment but

the structure of thegrains on this foram look like forams themselves...


star sand cytoplasm2.jpg

Source: Rottger and Kruger, (1990)

An old photograph showing star sand feeding. Forams move and feed

using 'threads' of cell fluid that poke out of holes in their tests - in this

case through holes in the spines.


Star sand harvests microscopic diatoms. Like plants diatoms containchloroplasts which turn sunlight into food. Star sand collects diatoms

in its cell where they are placed near tiny 'windows' where they can

more easily catch the sunlight and turn it into food.

Foraminifera Shapes to Colour

Foraminfera to colour


Life Inside a Single Cell

1: 1000,000,000,000,000

Forams have only ONE cell. A human being has TRILLIONS!

An organsm is divided into pieces called cells. Cells are tiny compartments which hold all the biological equipment needed to keep an organism alive and successful.

The main job of a cell is to organize its organelles to do their jobs. Because forams have only a single cell they can't grow very big. More about Cells

The Star Sand is able to move, feed, reproduce and survive in the ocean using only one cell!

Discover how it works...

cell picture
Explore a Cell

Colour a Cell

Colour a Foram Cell

Play the Cell Game - In the Allen Centre

Cell Game Printables:

Print the pieces to make your own game


Fimo kinesin game pieces ready for "Escape the Cell" -

Cell Game Number 2....



Escape the Cell

Follow Keziah and Ginny as they make Cell Game Number 2.
4 players throw the dice to race their kinesins along the microtubules criss-crossing through the cytoplasm to the other side of the cell.
No matter what number they get on the dice, they must stop on the red stickers to get more energy to transport food to all the organelles.

Painting the cytoplasm...

Mapping out the microtubules...

Explaining the job of the kinesins in the cell to Mrs Nyhof...

Microtubules with red energy points complete...

Adding some cell organelles to complete the picture and the finish

points in the cell wall... kinesins in place at the Start...


Final details...


How to Play..

A game for 4 players.

Throw the dice to move the kinesins along the microtubule maze.

No matter what the throw the kinesin must stop when it lands on

a red energy point.

Kinesins may move forwards or backwards.

Kinesins may land on the same points and pass kinesins in the way.

An exact throw is needed to enter the escape points.

If the number is too large to enter the escape points exactly, the

kinesin must complete the throw by moving backwards.