Topic 11: immunity

[Virtual Presenter] We hope that by the end of this lesson, you will have a deeper understanding of how our immune system works and how it plays a crucial role in our overall health and well-being. Let's begin by discussing phagocytes. Phagocytes are a type of white blood cell that play a critical role in protecting our bodies from infections. They are called phagocytes because they engulf and phagocytose (digest) invading microorganisms, such as bacteria and viruses. There are two main types of phagocytes: polymorphonuclear leukocytes (PMNLs) and macrophages. P-M-N-Ls are found in the blood and in many tissues throughout the body. They are the most abundant type of phagocyte and play a key role in fighting infections in the respiratory system. Macrophages, on the other hand, are found in many tissues throughout the body and play a key role in fighting infections in the liver and other organs. Both P-M-N-Ls and macrophages have receptors on their surface that allow them to recognize and engulf invading microorganisms. Once inside, they use a variety of mechanisms to kill or destroy the microorganisms. Next, let's discuss lymphocytes. Lymphocytes are another type of white blood cell that play a critical role in protecting our bodies from infections. They are called lymphocytes because they originate in the lymphoid organs, such as the spleen and lymph nodes. There are two main types of lymphocytes: T cells and B cells. T cells are responsible for recognizing and destroying infected cells directly, while B cells produce antibodies that can bind to and neutralize invading microorganisms. Both T cells and B cells have receptors on their surface that allow them to recognize and respond to specific invading microorganisms. They also have mechanisms in place to distinguish between self and non-self cells, which prevents them from attacking our own cells. In summary, phagocytes and lymphocytes are two types of white blood cells that play critical roles in protecting our bodies from infections. Phagocytes engulf and destroy invading microorganisms, while lymphocytes produce antibodies that can bind to and neutralize invading microorganisms..

[Audio] Hello everyone, welcome to lesson 11.3 of topic 11: immunity. Today we will discuss white blood cells, commonly known as phagocytes and lymphocytes. Every second of your life you are under attack by bacteria, viruses, and fungi trying to make you their home. However, your immune system is here to protect you. It has 12 different jobs, and 21 different cells and 2 protein forces that work together to keep your body safe. First, let's talk about phagocytes, which are guard cells that protect every border region of your body. When a bacteria enters your body, the phagocytes, in this case, macrophages, intervene. They swallow the intruder whole and trap it inside a membrane. Then, the enemy gets broken down by enzymes and is killed. Additionally, they cause inflammation by ordering the blood vessels to release water into the battlefield, making fighting easier. If the phagocytes can't stop the infection, the next line of defense arrives in the form of neutrophils, which fight so furiously that they kill healthy cells in the process. They generate barriers that trap and kill the bacteria. Now, let's move on to lymphocytes. These cells are responsible for identifying and targeting specific enemies, such as viruses. When a virus enters your body, lymphocytes, in this case, helper T cells, activate. They duplicate thousands of times and some become memory cells that stay in the lymph node and will make you practically immune against this enemy. Finally, we have B cells, which produce antibodies that are engineered to bind to the surface of the specific intruder. When a B cell and a T cell with the same set up meet, Hellbreak's loose. The B cell duplicates rapidly and starts producing millions of little weapons. They work so hard that they would literally die from exhaustion very fast. In conclusion, the immune system is a complex little army that has 12 different jobs, and 21 different cells and 2 protein forces that work together to protect your body. Life is awfully complicated, but if we take the time to understand it, we always encounter endless wonders and great beauty. Thank you..

[Audio] We will be discussing White Blood Cells or Phagocytes & Lymphocytes today. These cells play a crucial role in defending our bodies against infections and diseases by fighting various types of infections and removing foreign substances from our body. There are different types of White Blood Cells, and each one has a specific function. In this presentation, we will be discussing seven types of White Blood Cells: Monocytes, Macrophages, Eosinophils, Neutrophils, O, Mast Cells, and Basophils. Let's start with Monocytes. Monocytes are large, round cells that have a nucleus in the center. They are primarily responsible for fighting bacterial infections in the bloodstream. Next, we have Macrophages. Macrophages are large cells that engulf and digest foreign substances in the body. They also play a crucial role in helping the immune system identify and remove pathogens from the body. Eosinophils are cells that help to fight allergies and asthma. They are responsible for releasing histamine, which causes inflammation. Neutrophils are cells that fight bacterial and fungal infections in the body. They also play a crucial role in identifying and removing damaged cells from the body. O is a type of White Blood Cell that is found in the spleen. Its primary function is to filter out damaged cells from the.

[Audio] White blood cells, also known as phagocytes and lymphocytes, play a critical role in identifying and eliminating harmful pathogens, such as bacteria and foreign particles, and presenting their findings to lymphocytes. Phagocytes can ingest and kill these pathogens through the process of phagocytosis. There are two main classes of phagocytes: microphages and macrophages. Microphages specialize in ingesting bacteria, while macrophages primarily scavenge dead tissue and degenerated cells. Phagocytes are an essential component in our immune system and they are critical for maintaining our overall health and fighting infections..

[Audio] We are here to discuss the role of white blood cells, specifically phagocytes and lymphocytes in fighting infections and maintaining healthy tissues. Phagocytes are a vital component of our body's defense against infections. They are responsible for removing dead and dying cells that have reached the end of their lifespan, as well as for fighting off invading pathogens. During an infection, chemical signals (cytokines) attract phagocytes to the site of the invasion. These cytokines may come from the bacteria themselves or from other phagocytes that are already present in the body. Once the phagocytes arrive at the site of the invasion, they use a method called chemotaxis to move towards the source of the cytokines. When they come into contact with the bacteria, receptors on the phagocyte's surface bind to the bacteria, leading to the engulfing of the bacteria by the phagocyte. This process is crucial in fighting off infections and maintaining healthy tissues. Without phagocytes, our bodies would be vulnerable to invading pathogens and would struggle to maintain a healthy state. Thank you for listening, and we'll continue with our presentation on Topic 11: immunity..

[Audio] Hello everyone, good afternoon. Today, we'll be discussing phagocytic cells and lymphocytes, two types of white blood cells that play important roles in our immune system. Phagocytosis is the process by which these cells engulf and destroy pathogens, such as bacteria, viruses, and other foreign substances. As shown in the diagram, the process of phagocytosis involves several steps. First, the phagocyte attaches to the pathogen through a receptor on its surface. Next, the phagocyte engulfs the pathogen by forming a phagosome, which is a specialized compartment within the cell. Finally, the phagocyte destroys the pathogen and releases any remaining waste products back into the body. There are two main types of phagocytic cells: neutrophils and macrophages. Neutrophils are found in high numbers in the blood and are responsible for fighting bacterial infections, while macrophages are found in tissues and are responsible for fighting viral infections. In addition to phagocytic cells, there are also lymphocytes, which are immune cells that help to identify and destroy foreign substances. There are two main types of lymphocytes: B cells and T cells. B cells produce antibodies, which are proteins that recognize and bind to specific antigens, while T cells help to destroy infected cells directly. I hope this lesson has helped you to understand the process of phagocytosis and the role of phagocytic cells and lymphocytes in our immune system. Thank you for your attention..

[Audio] Good afternoon class. Today we will be discussing the topic of immunity, specifically focusing on white blood cells phagocytosis and lymphocytes. Phagocytosis is the process in which white blood cells engulf and digest foreign particles, such as bacteria and viruses. After phagocytosis, macrophages and dendritic cells can also participate in antigen presentation, a process in which a phagocyte moves parts of the ingested material back to its surface. This material is then displayed to other cells of the immune system. Some phagocytes then travel to the body's lymph nodes and display the material to white blood cells called lymphocytes. This process is important in building immunity. Lymphocytes are specialized cells of the immune system that help the body recognize and fight off foreign substances, such as bacteria and viruses. In conclusion, phagocytosis and lymphocytes play an important role in immunity and protecting the body from foreign substances. It is important to understand how these processes work and how they can be disrupted by illness or infection..

[Audio] Good morning/afternoon/evening everyone, and welcome to lesson 11.3 of Topic 11: Immunity. We will be discussing the role of white blood cells, specifically phagocytes and lymphocytes, in our immune system. Phagocytes are a type of white blood cell that play an essential role in our immune system. These cells are responsible for engulfing and digesting pathogens in our body. Phagocytes include neutrophils, monocytes, and macrophages. Lymphocytes, on the other hand, are a type of white blood cell that play a crucial role in our immune system. These cells are responsible for recognizing and destroying foreign antigens in our body. Lymphocytes include B cells and T cells. In our immune system, the M-H-C proteins play a crucial role in identifying and presenting antigens to our T cells. These proteins are released from the vesicle and travel to the outer surface of the cell membrane, where they bind with the T cell receptor. This binding allows the T cell to recognize and attack the antigen, which is carried by the M-H-C protein. The dendritic cell is an important antigen-presenting cell that plays an essential role in our immune system. When a pathogen is engulfed by a dendritic cell, the antigen is placed into a vesicle and released to the outer surface of the cell membrane. This allows the T cell to recognize and attack the antigen, which is presented by the M-H-C proteins. In summary, phagocytes and lymphocytes are both important types of white blood cells that play an essential role in our immune system. The M-H-C proteins are released from the vesicle and travel to the outer surface of the cell membrane, where they bind with the T cell receptor. The dendritic cell is an important antigen-presenting cell that plays an essential role in our immune system. Thank you for listening, and I hope you have found this lesson informative..

[Audio] We are now on slide 9 out of 15 in our presentation on Topic 11: Immune. In this lesson, we will be discussing the different types of white blood cells, specifically focusing on neutrophils. Neutrophils are the most abundant type of phagocyte in the bloodstream, constituting 50% to 60% of the total circulating white blood cells. These cells are ferocious eaters and rapidly engulf invaders coated with antibodies and complement, and damaged cells or cellular debris. We hope that this information has been helpful in understanding the role of neutrophils in the immune system. Thank you for listening..

[Audio] Our immune system is made up of two main types of cells, phagocytes and lymphocytes. These cells play a crucial role in protecting our bodies from foreign substances and infection. Phagocytes, also known as white blood cells, are responsible for removing cellular debris and bacteria, while lymphocytes are responsible for identifying and eliminating foreign substances. There are two main classes of phagocytes: neutrophils and eosinophils, and fixed and free macrophages. Lymphocytes come in two main types: B cells and T cells. By understanding the different types of white blood cells and their functions, we can maintain a healthy immune system..

[Audio] We have reached slide 11 of our presentation on Topic 11: Immunity. Today, we will be discussing Lymphocytes. Lymphocytes are a subtype of white blood cells in a vertebrate's immune system. There are three types of lymphocytes: natural killer cells (NK cells), T cells, and B cells. NK cells are responsible for the cell-mediated, cytotoxic innate immunity, T cells are responsible for the cell-mediated, cytotoxic adaptive immunity, and B cells are responsible for the humoral, antibody-driven adaptive immunity. These cells are primarily found in lymph, which is why they are referred to as lymphocytes..

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[Audio] We present lesson 11.3 of our comprehensive presentation on Topic 11: Immunity. In this lesson, we delve into the major cellular components of the adaptive immune response, specifically T cells and B cells. T cells, commonly known as thymus cells, play a critical role in cell-mediated immunity by directly attacking and destroying infected cells. B cells, on the other hand, are primarily responsible for humoral immunity, which entails the production of antibodies to neutralize pathogens. Both T cells and B cells are essential in your body's ability to recognize and eliminate foreign antigens. The process of antigen presentation is highly intricate, but it involves the identification of specific non-self antigens by T cells and B cells. Once an invader has been identified, the cells generate specific responses tailored to maximally eliminate specific pathogens or pathogen-infected cells. In this way, T cells and B cells work together to safeguard your body and promote overall health. Thank you for your attention, and we look forward to discussing this topic further in the next lesson..

[Audio] We are excited to present Lesson 11.3 of our immunity presentation. Today, we will discuss the crucial role of white blood cells in the immune response. We will focus on phagocytes and lymphocytes. Phagocytes are white blood cells that engulf foreign particles, break them down, and remove them from the body. Lymphocytes recognize and neutralize specific pathogens. We will discuss the two main types of lymphocytes: T helper cells and cytotoxic T cells. T helper cells produce cytokines that direct the immune response, while cytotoxic T cells produce toxic granules that induce the death of pathogen-infected cells. We will also discuss how white blood cells leave a lasting legacy of the antigens they have encountered in the form of memory cells. These memory cells are able to mount a strong and rapid response if the antigen is detected again. In summary, white blood cells play a crucial role in the immune response by engulfing and destroying foreign objects, recognizing and neutralizing specific pathogens, and leaving a lasting legacy of the antigens they have encountered. Thank you for joining us..

[Audio] We discussed the concept of white blood cells and specifically phagocytes and lymphocytes. We learned that white blood cells are an important part of the immune system and play a critical role in protecting the body from infections and other harmful substances. We reviewed what we've learned and addressed questions related to antibodies and antibiotics. We hope that you've gained a better understanding of the importance of the immune system in protecting the body from infections and other harmful substances..