“How do people survive in the jungle?” asks Lachlan (8)

Thank you team, for your comments.

You are right Homo Sapiens survived because of their hunting and gathering skills.They were better at it than their fellow humans  Homo Neanderthal and the other human groups (Homo erectus, Homo ergaster, Homo rudolfensis …..)

Some clever people have found, that we still have hunting and gathering skills in our blood. So there you are, we will/might be able to cope in a jungle environment.

Revised 11/11/17 – added other homo species.

Jessie (13) asked “Why do humans age until 100 years old in average and not further?”

The Hydra are a group of invertebrates (animals that do not have backbones) that look like tiny tubes with tentacles protruding off one end. They grow only about 0.4 inches (10 millimeters) long and eat even tinier aquatic animals AND they seem to be immortal, they can live forever without aging.

So why can’t we? There are several reasons. One of them is the inability of our cells to continually divide. The cells of bacteria seem to be able to divide, and form two daughter cells endlessly. Our cells only seem to be able to divide about 60 times …. so after that time the part of the body that the cells support begins to degenerate (die).

The cell dividing and subsequent regenerating is controlled by our DNA. It tells the body what to do. Over the years our DNA becomes damaged by a variety of things and the instructions for regeneration are lost.

However the hydra survives so maybe that will be a route for researchers to find some answers to the problems we face.

 

“How did evolution happen?” asks Parm (10)

 

Parm, it’s all due to some wonderful stuff called DNA however the beginning of life is at the moment attributed to  a simpler chemical called RNA. Somehow 4.5 billion years ago, in a hot chemical quagmire a collection of complex chemical structure was formed which was living, it could reproduce itself. It is thought that this microscopic entity was quite close to the structure of present day bacterias although, it’s make up was completely different. For example it didn’t breathe Oxygen, it is thought that it might have breathed a chemical called Ammonia and it expelled Oxygen. It also, in its structure contained a crude DNA structure.

From this humble beginning all life on Earth evolved dictated by changes in the  DNA molecules that were part of their structure. Plants, Insects, Bacteria, Animals, Fungi, Algae,  all life contains their own DNA molecules which dictate their continued existence.

So for Jeremey, our snail there has been, for some reason, a small change in her/his DNA. The spiral is wrong. Maybe it might be wrong but it might help Jeremy eat a plant that he/she couldn’t eat before and therefore survive and breed more snails like him/her.

Over the millions of years that life has existed on our Earth, now and then, new life , created by old life, experiences a slight change in the DNA, and that means that the new life is slightly different from the life of its parents (plants, animals, fungi ….). If the new life survives, that life will create more new life in it’s form, evolution has taken place.

Hope this makes sense Parm. Any thoughts? Write them in the ‘Leave a Reply’ box.

Kelly (9) asks “Why when we have been in water for too long, does our fingers and other parts of our body become soggy and wrinkly?”

Thanks team, a good start. The water soaks into the dead skin. There is lots of dead skin on our hands and feet. There are parts of our bodies which have very little dead skin so you will find that the wrinkles do not appear there. It was thought that the soaked up water caused the skin to swell and get puffy and the wrinkles were formed.

However

It is now thought by some that the wrinkling is a nervous reaction to the water attack on the body and that the wrinkled skin is a counter reaction to the skin becoming slippery because of the water intake (wrinkles help you hold things). What do you think?

Maybe you could record your thoughts in the Leave a reply box

 

“How do your eyes work?” asks Jeff (11)

Jeff

I have tried to make the image below to show you how it works. The eye is complex and is made of lots of different things. For example it has it’s own sets of muscles which can stretch the lens and allow your eye to move. It is filled with a special fluid that allows light to pass through it and gives the whole eyeball a very ‘squashy’ feeling. It is also connected to the brain by something which we call the optic nerve. The optic nerve transfers the electrical signal created by the image to the brain.

You also have two eyes and one of them is more dominant than the other.

Try this little experiment.
Look at an object in the room and then hold a finger out in front of both of both of your eyes and look at the same object. Then close one eye while looking at the object, then open the closed eye and close the open eye. What happens to the object that you are looking at? For one of your eyes the object that you looked at did not move.That is the dominant eye.

Jeff you can make a comment or ask another question.

(Anyone reading this post who wants to ask a question or make a comment please feel free to do so)

Sadie (8) asked “How do touch screens like iPods work?”

Sadie, I and my team  have already answered this question. See this answer to Rainnie.

To check on whether a question has already been asked go to the right hand column there is a SEARCH THE SITE  box. Type a keyword , like ‘Touch’ into the box and then click enter on your computer. It will lead you to the answer I have connected you to .

Sadie, thanks for the question. It shows how important it is to Search First.

If  you are uncertain about some bits of the answer then please feel free to Ask Another question.

“Why do metals always feel cold when I touch them?” asks Chen (8)

My question is, are the metals colder or warmer than the things around them? We need to test this question. So how?

We need find out if other materials behave in the same way.  We therefore need to test it with other materials, for example, wood, plastic, china and glass.

To make the test fair (an important part of my experiment) we need to make sure that all of the materials are at the same temperature at the start of the experiment. We can test this by taping a thermometer to the materials, leaving it there for a period of time (maybe 5 minutes) before touching each of them. Do they feel hot or cold? Do they feel like they are at the same temperature that you are.

What did you find out? If the metal, or other material did feel colder, or warmer, than the others then why?  Let me know what you think by filling in the Reply box below and post your comment or ask another Question . Anybody can do this.

Ethan (8) asked “How can you hear things?”

 

Ethan. There are some other small experiments I would like you to try.

Find a ticking clock and a box that you can put it in.  Listen to the ticking with the lid on and the lid off. could you hear the ticking when the lid was on?  Now with the lid on get a cardboard tube (maybe one from a tube of kitchen roll) , put one end of the tube on the box lid and the other end over your ear. Listen. Is the sound of the ticking louder when you use the tube? Move your ear away from the tube. What happens to the ticking?

Ethan, lots of questions from me to you.  Maybe the experiments have created some more questions. Any reader can ask a question or leave a Comment in the Leave a Reply box below

Also see Clara’s question on sound.

“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