How does a hand function?

For the past two hours in hurumanu 2, we have been learning about the muscles in the body and how they work. We were also learning about how that hand functions. There is a total of 19 main bones in each of your hands. There are three in each of the fingers apart from the thumb which has 2 and then 5 bones in the palm of your hand that lead up to each of the fingers. The purpose of the bones in your fingers is to provide structure and support. Joints are where two bones meet, the purpose of a joint is to create flexibility and allow movement between bones. Ligaments are what attach the bones together and they allow restricted movement. Did you know that there are NO muscles in our fingers! there are only muscles in our forearm and palm. Tendons play an important role in the movement of your hand, they are the strings that attach muscle to bone. We have five long tendons that run from the tips of our fingers down to the muscles in our palm and forearm. The muscles that are attached to our phalanges by the tendons move our fingers by contracting and relaxing. As the muscle contracts, it pulls down on the tendon making your fingers curl down and bend. 

For our hands-on activity (pun intended) we created a paper version to further understand how our hands work. The materials used were 5 pieces of around 30cm thread, I piece of paper, a pen, 2 straws, scissors, a needle, and tape! To make the hand you first have to cut out the hand shape that you can either print out of trace (either is fine) After cutting out the hand you need to cut the straws into 3 small pieces for each of the fingers and two for the thumb, Then 3 long pieces to connect the fingers to the bottom of the main sheath, then cut 1 piece for the sheath. Then stick on all of the straw pieces on with tape and be careful not to squish the straws too much. Then take your five pieces of thread and tape the ends onto the back of the fingers and put the thread through the needle. Then take your needle and thread it through the straws on each of the fingers. After threading the string through each of the fingers there should be five pieces of thread sticking out from the bottom, if you have five then you are finished! Now if you pull on each of the strings you will find that the fingers curl inwards just like a real hand!