How much caffeine in coffee?

We worked with caffeine in combined science a few weeks ago But how much caffeine is there in coffee and how does it work?

What if all the ice melted?

How would the world look if all the icecaps in the world melted and the sea level rised?

National geographic have made some nice interactive maps

Heart rate and exercise

Last week we looked on how exercise affects the heart rate. The video can be found here

The effect of adrenaline

We looked on adrenalines effect on peak power and heart rate today. Here are the movies we used

Adrenaline is one of the many hormons that makes up the amazing control system that works trough our bodies-

All hormones are chemical substances produced in a gland in the body, that are carried by the blood and alters the activity of one or more specific target organs and then is destroyed in the liver.

Adrenaline is the action hormone. It comes from the adrenal glands above the liver. When we are subjected to a sudden stress, the brain signals the gland to release adrenaline into the bloodstream.

Adrenaline increases the heart rate, and increases the oxygen supply to the body and brain. It also causes the liver to release glucose into the bloodstream, and the body to break down fat at a faster rateSo, it primes the body for sudden action, and supply extra supplies for respiration.

It prepares you to either fight or run away.

Too much adrenaline is not beneficial, as motor control and skills tend to degrade one the pulse gets above 150-150 BPM, but some adrenaline will make you stronger and faster

Long time stress, on the other hand, can break down the body and make it weaker, but for short time stress actions, we have a super effective system.