Have you ever wanted to see what DNA actually looks like? Well try this great experiment, which shows you how to isolate the DNA of a strawberry…

Strawberry DNA Isolation

This author of this article is the ARC Centre of Excellence in Plant Energy Biology.

ARC Centre of Excellence in Plant Energy Biology

The ARC Centre of Excellence in Plant Energy Biology focuses on the discovery and characterisation of the molecular components and control mechanisms that drive energy metabolism in plant cells. The Centre operates in three major university nodes across Australia: the University of Western Australia (Perth), Australian National University (Canberra) and the University of Sydney.

The Centre combines world-leading expertise and experience in organelle biology (chloroplasts, mitochondria and peroxisomes) with complementary expertise in genomics, proteomics, metabolomics, biochemistry and physiology. Four research programs within the Centre work towards identifying the mechanisms by which subcellular energy metabolism and communication systems control plant growth and development.

Research is carried out using four cutting-edge technology platforms on the model plant Arabidopsis thaliana to identify the key regulatory factors that control the biogenesis of organelles and their role in energy metabolism. This knowledge contributes to resources and knowledge for improving plant performance, particularly in marginal environments and in response to climate change, thereby providing the means to enhance the yield and nutritional value of a range of agricultural products.
Visit www.plantenergy.uwa.edu.au for further information.

This activity shows you how to make a star projector. You will be able to make the constellation Scorpius shine on your ceiling and walls.

This activity is from CSIRO’s free weekly e-newsletter Science by Email.  Each issue includes science news, a hands-on activity to do at home, a quiz and more. Visit www.csiro.au/sciencemail to subscribe. Want more hands-on activities? Visit CSIRO’s DIY Science pages and the Science by Email activity archive

Warning: This activity requires the use of a sharp compass. Be careful not to prick yourself.

You will need

• torch
• printer
• paper
• cardboard
• pencil
• tape
• scissors
• compass
• mailing tube*

*These are the type of tubes you would use to mail a poster.

What to do

1. Place your torch on a piece of cardboard with the light facing the desk. Trace a circle around the face of the torch.
2. Cut out the circle and fold it in half. Cut a small semicircle out of the cardboard along the fold. It should be less than a centimetre wide. When you open it back out, it should look like a round hole in the centre of the circle.	Cut out a circle the size of the face of your torch. Fold it in half to cut a hole in the centre.
3. Tape the cardboard over the face of the torch. We also taped around the clear edges of the torch to minimise the light spilling out of the sides.	Tape the circle to your torch. You may also need to tape any gaps.
4. Print off the template, preferably onto cardboard.
5. Take the caps off the end of the mailing tube.
6. Place the end of the mailing tube over the template so that all the black dots are covered up. Trace a circle around the outside of the tube.
7. Use the compass to poke through the template where the black dots are. Wiggle the compass around at the larger dots to make a larger hole.	Cut out the template to the correct size and punch holes in it where the dots are.
8. Use tape to fix the template onto the end of the tube. Make sure that the side with the printing is facing outward.	Tape the template to the tube.
9. Find somewhere dark and shine the torch through the tube at the ceiling or wall. You may need to move closer or further away from the wall to see the stars at their finest.	Shine the torch through the tube and onto the wall or ceiling.

What’s happening?

A constellation is a group of stars that make up a picture in the sky.  Although the stars form a pattern in the sky from Earth, they may not be related at all. The stars in a constellation can be hundreds of light years apart.

The story of the constellation Scorpius is based on ancient Greek mythology. Scorpius was a scorpion sent to kill Orion, the great hunter. The two constellations are on the opposite sides of the sky. Orion sets as Scorpius rises, symbolising the fall of the hunter.

If you can, head outside to see if you can find Scorpius in the night sky. The brightest star in Scorpius is called Antares. You may be able to see it glowing slightly red. It is a red supergiant star with a diameter about 800 times that of our sun. Red supergiant stars are the largest stars in the universe, but do not necessarily have the greatest mass.

Applications

Light pollution is artificial light from streetlights, shopping centres, and other outdoor lighting. It makes the night sky brighter and the stars more difficult to see.

Later this year, as part of National Science Week, Australians will be asked to take part in the Big Aussie Star Hunt (BASH). Part of this project includes a light pollution survey.

All you need to do for the survey is count the stars you can see in Scorpius. The more stars you see, the less light pollution there is. List your observations on the website to contribute towards making a light pollution map of Australia. This map will help show where we can save energy and help the environment.

BASH will also show you how to find other constellations, teach you how to find south using the stars and help you find out more about Indigenous astronomy.

BASH is a project initiated by CSIRO and coordinated by the ABC. Visit the BASH website for more information.

Try another Science by Email activity using astronomy
Timing the stars
Make a telescope

More information

Australian Aboriginal constellations
Build a planisphere
CSIRO’s Australia Telescope National Facility

This article is an initiative by CSIRO Education

This activity is from CSIRO’s free weekly e-newsletter Science by Email.  Each issue includes science news, a hands-on activity to do at home, a quiz and more. Visit www.csiro.au/sciencemail to subscribe. Want more hands-on activities? Visit CSIRO’s DIY Science pages and the Science by Email activity archive

Warning: this activity requires the use of a hot stove. Younger scientists should ask an adult for help. Be careful not to burn yourself!

You will need

• 2 litres of milk
• 1/3 cup of lemon juice
• large pot with lid
• thermometer
• wooden spoon
• colander
• cheese cloth
• string
• fresh herbs, salt and pepper (optional)

What to do

1. Heat the milk to 80 degrees Celsius in a pot on the stove and then turn off the hotplate. Make sure that you stir the milk while heating to stop it from burning and even for a short while after you have turned the heat off.
2. Add your lemon juice and stir well.	Pour the milk into the pot, carefully heat it to 80 degrees Celsius, then add lemon juice.
3. Put the lid on your pot. Let the mixture set for 15 minutes until the mixture separates into curds and whey. If the liquid (the whey) is still milky, add more lemon juice.
4. Line a colander with cheese cloth, then pour in the lumpy curds.	Once the curds have separated from the whey, strain the mixture using cheese cloth.
5. Tie the corners of the cheese cloth together. Hang the parcel to drain for 1-2 hours.	Tie the cheese cloth together and drain, allowing all the liquid whey to run out.
6. Remove the cheese. If you want to, add salt, pepper and herbs. Your cheese is ready to eat!	Add salt, pepper and herbs to taste. Enjoy!

Store your cheese in a sealed container in the fridge for up to a week.

What’s happening?

In this activity, you separated milk into curds and whey. This is the main step required to make any sort of cheese.

You’ve probably heard of curds and whey before, in the nursery rhyme Little Miss Muffet. Before being interrupted by a very rude spider, Miss Muffet was sitting down to a bowl of lumpy cheese and liquid, similar to what you have just made.

Milk has lots of protein in it. The lemon juice you added caused the proteins in the milk to become separated. The clumpy curds that become cheese are made from the milk protein, casein. Other cheeses are curdled by vinegar, or more typically by the addition of bacteria and an enzyme – a chemical to help the process – called rennet.

So, what is the difference between different types of cheese? There are lots of different milks that can be used for different flavours. This includes cow, goat, sheep and buffalo milk.

Some types of cheeses also have different bacteria added. These bacteria may require different temperatures and grow at different rates. In addition, mould may be added, or herbs, or smoke.

There are lots of different factors that come into play when making cheese, which is why there are so many yummy types!

Try another dairy-based Science by Email activity.

More information

Podcast: listen to a cheese researcher
In the cheese lab
Study cheese at Charles Sturt University

This article is an initiative by CSIRO Education