lunes, 29 de enero de 2018

New experiments

Now, we are going to grow lentils plants to study the effect of home pollutants on growth and development of lentils. This morning we have put 10 lentil seeds into containers with potting soil. We have recycled used yogurt cups for this experiment. We have watered them. When seeds germinate, we will treat them with the pollutants and we will study the growth of plants. We will have untreated plants, watered only with water, as control experiments. 

New results

We have repeated some experiments. Seed didn't germinate in water with detergent at concentrations of 5% and 10% (weight/volumen concentration). So, we have studied lentils germination at lower concentrations (1% and 0,5%). We have tested another washing up product and we have repeated the experiment with hydrogen peroxide. In the previous experiment, seeds germinate with high concentrations of acetone; this wasn't the expected results as this product is toxic. So we have tested the effect of nail polish remover on germination as this product contains acetone. No seeds have germinate with concentrations of 10% and 5% (w/v); we are going to test lower concentrations this week. Finally, fabric softener doesn't seem to affect lentils germination as concentrations as high as 20% doesn't inhibit germination.
Please, study this data and make your own conclusions. Write them as comments.

lunes, 22 de enero de 2018

Our first results

After a week, we have our first results. In our control experiments, all the seeds irrigated with water have germinated. But we have observed differences between treatments. Here you have a table with our results. What are your conclusions? Is there any experiment with unexpected results? Will we have to repeat any experiments?

Control plate
Washing up liquid, 5%.
Grease remover 5% and 10%.

A new research project for our younger students: Home pollutants

Surely, your family has lot of chemical products for domestic use at home. Some of them are detergent or fabric softener; we use them for washing our clothes. Bleach, grease remover or antilime cleaner are used for cleaning our houses. All of them contain toxic chemicals we leave to the environment. And it is the same with other products we use with our own body like the alcohol or the hydrogen peroxide we use to disinfect wounds or the nail polish remover we use for cleaning our painted fingernails. Do they affect living beings?
This is the main goal of the project we are beginning. We are going to study if this products are toxic for the environment, especially for plants. We want to know if they affect aspects of plants biology as germination, growth and development of plants.

We begin our experiments studying the effect of these products on the germination of seeds. We are going to use lentil seeds (Lens culinaris). We have prepared seed germination chambers with Petri dishes; we have placed paper towel inside the plates and we have added 20 ml of the different solutions of chemical products. We have put 16 seeds per germination chamber.

We are going to carry out control experiments. In some plates we will add only water. We want to know the viability of seeds irrigated only with water. Later on, we will compare the number of germinated seeds in plates with water and chemical products. We consider that seeds have germinated when they show a little root at least one millimeter long. We will study seeds germination for a week.

lunes, 18 de diciembre de 2017

A cave full of crystals

We are reading chapter 3. This is the first morning after professor Lidenbrock, Axel and Hans climbed down through the crater. The journey continues and they go into a big, dark tunnel. They are walking for a long time when they find thousands of beautiful crystals in the wall of the cave. Crystals, beautiful crystals... Would you like to have some crystals? You don't need to go to the centre of the Earth to get crystals. In fact, it is very easy.
We are going to prepare an experiment to get crystals in our laboratory. But you can do it at home too; in this case you need the help of your parents.
Take hot water and stir salt until no more salt will dissolve. As hotter the water more salt you will dissolve. Carefully pour the solution into a container and leave it somewhere it will not be disturbed (no movement, constant temperature...). Wait and you will grow beautiful crystals.
Take your crystals to our laboratory. You will get points to go to the centre of the Earth.

After Christmas hollidays we have the result of our crystallization experiment. Hear your have some pictures. Have you got your crystals? Take them to the laboratory!

Copper sulphate crystals obtained in our laboratory.

Crystallization I (Maxi Morteyrú)

Beautiful salt crystals, by Claudia Moreno Villegas.

Marvellous crystals, by Iris Luque Barrio

miércoles, 29 de noviembre de 2017

Compasses for Professor Lidenbrock

Fortunately, we have compasses to give to professor Lidenbrock. You have made some compasses, so the journey is going on. Here you have one picture with some of your compasses. You can see that all of them work correctly, all of them point to the North.
By the way! What have you learn about magnetism? How does a compass work? Why is there a magnetic field in the Earth?
Don't worry!!! These are difficult questions for students of the first course of ESO. But that the study of magnetism has been very important to know the inner Earth structure. Try to answer them. You know... extra points to travel to the centre of the Earth.

lunes, 27 de noviembre de 2017

A compass to travel to the centre of the Earth

Axel, Hans and Professor Lidenbrock have begun the Journey. Now they have climbed down the crater and they are 2.000 meters from the top of Snaeffels. In this morning, after breakfast, professor Lidenbrock looks for his compass to continue the travel but.... he has lost it. So, you have to help him and you are going to make your own compass.
Basically, a compass is a magnetic needle that points to the North. But how a needle becomes magnetised? It is very easy. Take a sewing needle and a magnet. Rub the magnet against the sewing needle at least forty times always in the same direction. The needle should be magnetized.
Cut a circle of craft foam, cork or EVA foam. Take a glass of water. Place the needle on the circle and place it on top of water, just in the centre of the glass. If every thing is correct, the needle will begin to slowly turn around and finally the needle will point North and South.
Make this experiment at home and take your compass to our class. If your compass points to North  our heroes will continue the journey and you will win points.

martes, 21 de noviembre de 2017

How many stars can you see from your house?

We are learning about the atmosphere in class. As you can read in our book, air pollution is the presence of various substances or types of energy in the atmosphere in quantities that are harmful to living beings and the environment. Gases, solid particles.... perhaps these are the most known pollutants. But there are more. Noise, for example, is a type of energy that causes important effects on living beings. And light? Can light pollute our cities?
In my opinion we are lucky because some of you live in the city and some in villages surrounding Granada. I want to propose you an experiment. I want you to look at the sky at night. Take a sheet of paper and cut a frame of 3 cm each side. Through this window look at the sky to the area with the highest number of stars. Count them!!! We will discuse your results in the classroom.
Please, write comments with your conclusions!!

(Marc Imhoff/NASA GSFC, Christopher Elvidge/NOAA NGDC; Image: Craig Mayhew and Robert Simmon/NASA GSFC)

An experience listening to music from your mp3 player

Are you fond of listening to music from a mp3 player? Do you always listen to music at the same level? Probably not; why? There is a lot of noise surrounding us. Cars, motorbikes, advertisements... every time is more and more difficult to hear to sounds we want to listen. I mean, our voices, conversations... This is what we know as noise pollution. And it is harmful to living beings. Humans can develop cardiovascular diseases due to noise pollution; in animals, reproduction or navigation can be altered. All of them will have hearing loss.
I propose you a simple experiment. You are going to listen to music in different situations. At night, when everything is silent; in a noisy environment (street with lot of cars and motorbikes, shopping malls...) and in an intermediate situation. Adapt the volume to the minimun you can hear and write down the number you read on the screen of your device. We will calculate in the classroom the average values. 
What are your conclusions of our experiments? Write them as comments. Try to do in English. I will pay special atention to your solutions for noise pollution!

lunes, 13 de noviembre de 2017

About volcanoes

This is amazing!!! Our heroes are going to travel to the centre of the Earth. They have discovered the entrance in the Snaeffels volcano. But we have read other messages with other volcanoes to begin our journey. But we have a little problem: we know the name of the volcanoes but we don't know where they are. 
If you want to go to the centre of the Earth you will have to discover where these volcanoes are: Mounts Etna, Apoyeque, Barva, Krakatoa, Kilimanjaro, Vesubio, Fujiyama and Mauna Loa. 
And I have found a postcard in an old book with a message that says that we can begin our journey from Spain. This is the picture. And I could only read a name: Santa Margarita. Where is that volcano? Are there other volcanoes in Spain? The answers as comments, please. You will win points!

And finally... If we want to begin our journey from a volcano, we must know how a volcano is.  Professor Lidenbrock is a geologist and of course he knows. But do you know how a volcano is? Please draw a volcano, locate all their parts and give it to me. I will put in this blog the best drawings, with extra points.
Iris's volcano 

 Claudia's volcano

Maxi's volcano

Pablo's volcano

 Rosa's volcano

 Ana's volcano
Lucia's volcano

And there are more volcanoes in this link.