Immune System - Fighting Microbes PDF

Name: ________________________ 40 Curriculum Connection B2.1, B2.2, B2.4 What is Your Immune System? Being immune means you are protected. That means your bodies immune system is designed to fight off infections and sicknesses. The immune system protects us against microbes. What are Microbes? Micro...

Name: ________________________ 40 Curriculum Connection B2.1, B2.2, B2.4 What is Your Immune System? Being immune means you are protected. That means your bodies immune system is designed to fight off infections and sicknesses. The immune system protects us against microbes. What are Microbes? Microbes are microorganisms that we cannot see that enter our bodies and cause diseases and illnesses. Microbes live in water, soil, and in the air. The five main groups of microbes are bacteria, fungi, viruses, algae, and protozoa. Many of the illnesses we get that cause cold symptoms such as coughs and runny noses are viruses or bacteria that enter our body. How Your Immune System Fights Microbes First Line of Defence The first line of defence is our skin. Microbes cannot enter our skin unless it is cut. That is why we wash our cuts and keep them clean. Mucous is also a barrier that microbes cannot pass through. The mucous in our nose and throat help prevent microbes from getting into our bodies. This means we should keep our fingers out of our noses, ears, and mouths. Second Line of Defence If microbes get into our bodies, the second line of defence is activated. Our bodies have white blood cells that fight against microbes. Phagocytes are a type of white blood cell that chew up invading microbes. Lymphocytes are the other type of white blood cells that allow the body to remember and recognize previous invading microbes so they can know how to destroy them. White blood cells are found in many different places in your body, including your spleen. Your spleen is an organ found in your belly that works to filter blood and fight infections. White blood cells are also found in bone marrow, which is a thick and spongy jelly that is found inside your bones. Getting Sick Avoiding all microbes is impossible and everyone gets sick sometimes. Luckily, we have immune systems that know how to fight microbes. The best way to prevent microbes is by washing our hands a lot. Every time you touch a new surface, dangerous microbes can be living there. When you touch microbes, you run the risk of the microbes entering your bodies in the food you eat, or when you touch your face. You can also keep your immune system strong by eating healthy foods, getting exercise, sleeping enough, and seeing the doctor for checkups. If you are sick, stay home so you don’t spread bacteria or viruses to others. © Super Simple Sheets supersimplesheets.com