Life Science Final

By Bekah Walter

Journal Entry day 1

Today I did the first five learning targets and learned a lot about the Immune system. I remember studying it before and thought I knew it pretty well but I learned a lot today. It got really in depth to the topics. I didn`t realize there were so many little names like pathogens and Inflammatory response.

Journal Entry Day 2

Today I learned a lot about HIV. Before I had heard of it and knew it was very dangerous but I didn`t know that so many people were infected with it. I also didn`t know you could have it for years but not actually feel sick until much later. I learned about T-cells and B-cells and what they do. I had never heard of those before!

Journal Entry Day 3

Today I finished up my project by adding all of my notecards information onto the presentation. I got to review over everything so that I know it is implanted in my brain. I understand the immune system a lot better now.

What is the relationship between pathogens and infectious diseases?

Pathogens are the things that cause infectious diseases like colds and flu. When you get illnesses like those you know that pathogens have gotten inside of your body and caused harm. Pathogens target individual areas of cells, like patches, and infect those. For example, if you come down with a sore throat it means the pathogens have gotten inside and started killing patches of cells in your throat. It can happen with many types of infectious diseases.

What kind of pathogens cause infectious diseases in humans?

The first one is bacteria which is a one-celled organism that causes a lot of diseases like ear infections, food poisoning, and strep throat. Some of them produce toxins to target the part of the body. The next one is viruses which are tiny particles, even smaller than bacteria. They cause mostly cold and flu. There are more than 200 different kinds of cold viruses. The third one is fungi. It grow best in warm, dark, and moist places. Athlete`s foot and ringworm are two diseases they cause. The last one that infects humans is protists which cause a lot of blood diseases such as malaria and amebic dysentery.

What are the four ways pathogens can be spread?

The first way is by contact with infected people like shaking hands with them or touching something they have used. The next one is soil, food, and water. Diseases can be carried through soil and when you work with it or plant things you could get it. Food can carry things like food poisoning that infect you when you eat it and water can infect you with things like E Coli when you swim or drink unfiltered water. If an infected person touches a surface or doorknob and you touch it the germs are left behind and you might become infected. That is the third way. The final way to become contaminated is coming across infected animals. It might happen by petting them, being licked by them, or getting bitten.

How does the body`s first line of defense guard against pathogens?

The first thing it uses is the skin. The skin has special chemicals in it to kill the pathogens and they fall off the skin with the dead skin. Then there are the breathing passages that uses the mucus to filter them when they are breathed in. The cilia also trap and remove them if they make it that far. The next one is the stomach and mouth. The saliva has enzymes and chemicals in it to remove everything before it goes into the stomach and if it does the stomachs acids can surround it and easily kill it. It then washes it out of the system.

What happens during the inflammatory response?

The fluids and white blood cells leak from the blood vessels into the nearby tissues. The white blood cells attack the pathogens until they die. This is the bodies second line of defense. It is its general defense. Most pathogens don`t make it past here because the white blood cells are the disease fighters of the body.

How does the immune system respond to pathogens?

The few pathogens that do get into here are treated by the immune system. It can easily distinguish between different pathogens. It has a different reactions and way to kill each one. The T-cells are the ones that identify and distinguish between them and the B-cells are the ones that follow-up to actually kill and destroy them.

How does HIV affect the immune system and how does it spread?

HIV is the only known disease that is able to target the T-cells and destroy them so that it can easily pass through to infect you. HIV reproduces inside of the T-cells. Once it has done that you can be infected fo years before you actually feel the symtoms. More than 40 million people are infected with it in the US. Most of them don`t even know it. Over 3 million of those are children. Your Immune System eventually loses its ability to fight the disease over a long time of it being there and that is how you actually begin to feel sick.

How does the body acquire immunity?

When a disease enters the body the antigens are immediately recognized and destroyed by antibodies. It remembers the disease and what to do next time it enters your body and attacks. Your body has a memory of each disease and knows how to fight it off. Another way to acquire immunity is to get a vaccination of a harmless form of a antigen so your body can recognize it in case you actually get sick and knows how to get rid of it.