The HIV virus destroys helper T cells. This allows the body to not be able to hold off invaders, as the immune system will have lost some of its major components. The reason that HIV is not the official cause of death in those who die with it inside their bodies is because the virus allows the body to be extremely vulnerable to other viruses and diseases. Without the immune system to help the body defend against invaders, a person can die from easy to contract illnesses such as a flu or other type of pathogen. In this way, the HIV virus does not directly kill a human being
In animals that are larger, the heart beats fewer times a minute. Heart rate equals .289 - .202 times the weight. This equation means that if an animals if larger in terms of weight, then it's heart will beat less than a smaller animal. An example of this is a hamptster, whose heart beats 450 times a minute and an elephant whose heart beats 30 times a minute. This equation has a lot to do with an animals expected lifespan because mammal hearts only can beat roughly between .6 and 2.2 billion times before it starts to deteriorate. Hearts no matter the size can only beat so many times just like machines that get worn out.In the lesson, I learned that there are different types of joints that connect bones. The three types of joints are ball and socket, hinge, and pivot joints. The ball and socket is the most mobile type as it can allow the appendage to rotate in all directions and gives the attaching joint the largest range of movement. The hinge joint and pivot joints allow for movement on one plane. An example of this is in the knee a hinge joint allows for forwards and backwards movement.
Because fast twitch muscles wear out much quicker, professional football players tend to be much younger than marathon runners. The marathoners make use of their slow twitch muscles, which last longer. Football players are also at a greater risk of tearing muscles as they play a contact sport. Marathon runners are at less of a risk because there is no contact in their sport and the majority of their injuries occur from not adequately stretching. Football players use their fast twitch muscles much more than their slow twitch muscles as they have to sprint for a short amount of time, then they have a short break before the next play. Marathoners use their slow twitch muscles more because they need to be able to last for a long time on their energy.
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AuthorMichael Tellini Archives
May 2014
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