“If all living things were in one food chain, what would be at the top?” asks Chelsea and Ashli (10)

Thanks team. I found a nice little revision site on food chains that you might like to try, find it at Food Chain Game.

Now to your question. Firstly it might be a little difficult putting all living things into one food chain. Secondly do you think it would be humans?  Ecologists (They are scientists who specialise in studying the living environment) rank species by their diets using a metric*  called the trophic level scale. Plants, which produce their own food, are given a rank of 1. Herbivores, which eat only plants, are ranked 2. The fiercest of meat-loving predators, such as killer whales, are rated at 5.5. Humans are rated at 2.5 which is the same level as a pig.

If you want to make a comment please use the box below or you could ask another question.

* metric as a noun means a standard scale of measurement so you could call a temperature scale a metric or any other standard scale of measurement a metric.

(updated 13/9/17 -changed metric to measurement)
(updated 15/9/17 – ‘measurement’ back to ‘metric’ after realising it was the correct word in the context in which it was presented, added addendum explaining it’s use as a noun)

“What was the first plant that ever grew on Earth?” asks Mahdiyat (8)

So what now? Thanks team, some good answers.

It would be great if we could do some small investigations using Moss.

1.Firstly let us confirm that the moss has no stems or flowers.

2. Secondly a more long term experiment. Try ‘planting’ your moss on a rock. Before planting look closely at the surface of the rock. compare the surface 6 months after planting (and not disturbing the Moss).

Now a story ……..

The moss was the Earth’s first plant and it took over the world. It damaged the rocks it settled on and it took all of the Carbon Dioxide out of the atmosphere. This made the Earth very very cold (the first ice age). The coldness killed most of the moss and as the Carbon Dioxide built up again it allowed other plants to share the Earth with it.

 

“Why does my banana skin go brown when I peel it off? asked Gina (10)

Gina, it seems to be something about the ‘breaking’ of the skin of the fruit, which lets  in oxygen and allows it to react with some of the fruits chemicals.

We could test that idea. One way to test it might be to try and stop the ‘breaking’ of the skin of the banana. Can you think of a way of removing the skin without breaking or damaging it?

We could also test the role of oxygen. Any ideas how? If you have an idea why not try it  by comparing the speed of ‘browning’ for your oxygen and ‘no oxygen’ banana skin?

Remember to try and make the tests as fair as possible. Think about what that may mean. Remember a fair test means only changing one thing at a time while you try and keep all other things constant.

Let me know how you got on by Leaving a Reply in the box below.

Preethikha (13) asked a question about planting corn seeds in clay.

Preethikha you asked your question on behalf of your friend  Johan who appeared to be having trouble in growing his corn seeds in clay. I asked my friends about this and these were the ideas that they arrived at. 

The roots of the corn plant are very complex like most plants and they NEED oxygen . Clay is an important soil, it is full of nutrients which are important in providing the growing plant with food , HOWEVER  it is very different from most of the soils that we meet in our gardens.

Soils are composed of three types of particles: sand, silt, and clay.

The size of the particles varies, with clay having the smallest size and sand the largest.Smaller sized particles pack more closely together and slow the flow of water through the soil.The composition of a soil can affect the permeability (flow) of water through it.

There is the possibility that your friends corn seeds produce roots which are then ‘drowned’ in the surrounding clay soil. Investigate your friends soil and compare it to other soils in your neighbourhood. My next question for you is how would you go about investigating it ?

 

A question “How does the world work”

Some time ago a well known scientist (James Lovelock) suggested that the Earth (our planet) was special. He claimed that the Earth itself was a living thing and had control over its environment. He gave the Earth the name Gaia (a Greek name for the goddess of the Earth) and suggested that the planet’s objective was to support life on it, at all cost.

It has been argued, by those who support this idea, that there is a lot of evidence from investigating the Earth’s history over the last 3 billion years, that suggest the idea is valid. Below are some of those arguments. What do you think?


Note
The Gaia idea is something called an hypothesis (an idea). It has yet to be proven. If proven it can then be called a theory.

 

Ruby (8) asked “What type of chemical is in capsicum that hurts when police put it in eyes?”

Yes, a great question Ruby. There is this temptation to relate Capsaicin to Black Pepper, however this is not true. The black pepper seeds are from a plant in the vine family of plants. The Capsicum family is the home of the chillies and the chemical Capsaicin which is a chemical in the alkaloid family. Capsaicin is not only used in pepper sprays it also has some curative properties, for example it is an effective pain killer.

I think it is very interesting that certain chemicals, particularly those derived from plants can be used for destructive purposes and for curing purposes. Just a thought.

“Am I living?” asked Cloe (7).

Many thanks team. You are right there was a question about clouds  and if they were living. Think about what living means for you and for other things that might be living.

Do you think that plants, rocks, clouds, germs, the air, birds, trees and you are living?  You might not think that a tomato is living BUT does it contain seeds? Think about seeds and what happens to these non-moving, non-growing things. Are they living? So put them in some water and give them some soil, what happens?

Any reader can ask a question or leave a Comment in the Leave a Reply box below

Science Master Special – What might plants need to grow?

1. Air (Oxygen and Carbon Dioxide)
2. The Sun or some light or maybe some darkness.
3. Warmth (heat), or maybe some coolness.
4. Water (moisture, dampness)
5. Soil, rocks, compost, sand.
6. Time, lots or maybe little.
7. Creatures, in or above the soil. These could be giant worms or miniscule creatures.
8. Plant food. Fertilisers, minerals.

 

This list was helped by The Nuffield Space Project P77

Imran(7) asks “Why do plants need soil?”

Imran, many thanks for your interesting question. I have some thoughts but I will start by asking my team.

Thanks for that team. I have had some thoughts about some of the things that MIGHT be needed by plants to help them grow. You can see my thoughts on one of my SMS pages I got 8. See how many you can get before you see my list. Did you get as many a me? Do you think they are all correct? Are there any more? Let me know by clicking on the ‘Reply’ button below.

If you are happy with your answers then how could you test them, fairly?
For example how do you do a fair test on the effect of light/darkness on a plant? What do you vary and what do you keep the same?

Good luck. Let me know how you got on.

A ScienceMaster Special – Measuring the height of a tree using a pencil and a friend

Now and again I will mention some magical experiences.

This  was a technique given to me by a teacher at Severne Primary School in Birmingham.

Do you want to measure the height of a tree and all you have is a friend and a pencil?

First task line up the vertical pencil with a tree.

tree1

Second task get a friend to stand at the base of the tree.

tree2

Third task. Make the tree fall over. Not really, just make the pencil fall over.

tree4

 

Fourth task. Ask the friend to walk from the base of the tree to the end of the pencil, counting her/his steps. Shout stop when he/she reaches the end.

tree5

Fifth task. Work out the height of the tree. A step is about  60cm. You might need to check this with your friend, what is his /her step distance.

So what is the height of the tree? Any answers…..click on the ‘Leave a Reply’ and leave an answer.