Study Guide Power Point The following power point is split into the these topics: • Endocrine/Nervous System • Immune System • Breakdown in immune system Nervous System - Endocrine System - Hormones Sending Signals • What are the primary agents that the brain or a gland uses to communicate with other cells? • Hormones • Neurotransmitters (Nerve chemicals) Terminology • Secrete (verb): to produce and then release a substance • Gland (noun): a cell or organ in the body that synthesizes a substance and then releases it for use by our body • In order for your body to cool off, the sweat glands secrete water. • Target cell (noun): any cell that contains receptor molecules to bind hormones • Receptor molecule (noun): molecules, proteins, found on the outside of the cell that receive chemical signals (hormones) from other cells Hormone and Receptor molecule must fit in order to work Gland Receptor molecule Hormone Hormones • Signals released by glands so cells can communicate • Hormone has to fit on receptor molecule of the target cell Failure of hormone to work means either the 1. Receptor molecule is the wrong shape 2. The hormone is the wrong shape 1. The diagram below shows a biological process. Explain why the hormones attach to the target cell and not to other cells in the diagram The target cell has the receptor molecule with the specific shape that the hormone will fit Hormone and receptor molecules • Remember that these molecules are proteins. • An improper shape means a incorrect Amino Acid sequence Amino Acids Immune System Ms. Blalock, Ms. Hartsell, Mr. Luckman Immune System ● When first exposed to disease, organisms make specific antibodies to mark the foreign invaders so the white blood cells know what to destroy. ● If exposed to the same pathogen again, the immune system has a memory and can quickly make similar antibodies that will match the SAME antigens as the sickness from the previous time. ● REMEMBER: since Antigens and Antibodies are proteins that specific shape that match. SHAPE DETERMINES FUNCTION Illness and Germs Pathogens is the term that refers to all germs and microbes that can cause illness in an organism? Bacteria ● Bacteria are single-celled organisms. ● They are alive because they can carry out the characteristics of life without needing the help for another organism Activity # 2 – Specific Immune Response • What does “specific” mean anyways? – “Specific” is someone or something that is specially suited for a purpose or need. – An example of “specific” is someone saying exactly which jacket they want someone to grab for them. Activity # 2 – Specific Immune Response • A specific immune response involves… – Antigens antibodies and • In daily life we might speak of viruses, bacteria, and toxins. However, when reading about the immune system you’ll often come across the words antigen and pathogen. • An antigen is a foreign substance that triggers a reaction from the immune system. Antigens are often found on the surfaces of bacteria and viruses. • A pathogen is a microscopic organism that causes sickness. Hostile bacteria and viruses are examples of pathogens. • Some white blood cells make a specific protein, called an antibody, that will respond to an antigen. Antibodies are released from the white blood cells so that they can seek out intruders and help destroy them. White blood cells produce antibodies at an amazing rate and can release tens of thousands of antibodies per second. • When the Y-shaped antibody finds a matching antigen, it attaches to it. The attached antibodies serve as an appetizing coating for eater cells such as the macrophage (a white blood cell that eats pathogens). • Antibodies also neutralize toxins and viruses, preventing them from infecting new cells. Each branch of the Y-shaped antibody can bind to a specific antigen, so while one branch binds to an antigen on one pathogen cell, the other branch could bind to another cell - in this way pathogens are gathered into larger groups that are easier for macrophages to eat. Characteristics of Life ● Repair injury ● Reproduce ● Communicate ● Digestion/Excretion Viruses ● Viruses are non-cellular (not a cell) ● They are dead because they cannot performs] the characteristics of life without having a host. ● The infects to cause illness and death. Cures and Treatment ● Diseases caused by a bacteria can be cured because the bacteria can be killed. ● Doctors inject a person with antibiotics to kill the bacteria ● Viruses cannot be killed because they are NOT alive so there is NO cured for them ● Vaccines can PREVENT viruses from infecting organisms Bacterial infections • How are bacterial infections treated or cured? • They are treated with antibiotics prescribed by a Doctor Vaccines Vaccinations use dead or weakened microbes (virus) to stimulate the first production of antibodies They are not as strong as the disease so the person does not get sick Helps organisms build a memory of antibodies. Vaccine Process ● A dead or weaken virus is injected into an organism ● The immune systems recognizes the virus and synthesizes antibodies ● The immune system makes a memory of the virus so when the real virus (not a dead or weak one) comes it can use the antibodies to stop it immediately. Breakdown in Immune System Organ transplant When an organ is replaced with an organ from another person. The organ can sometimes be seen as a “foreign invader” from the immune system Cell surface proteins Transplanted organs have different or foreign antigens on their cells. This is similar to how the immune system sees a virus or bacteria cell Different cell proteins Donor cell proteins Receiver’s cell proteins These cells are not a match for an organ transplant Organ transplant rejection • Organ transplant will reject if proteins do not match • Immune system will trigger white blood cells to attack the transplanted organ Immunosuppressants Immuno - immune system suppressants - lower Immunosuppressants are drugs that lower the immune systems response to transplanted organs. Activity # 2 – Specific Immune Response • What does “specific” mean anyways? – “Specific” is someone or something that is specially suited for a purpose or need. – An example of “specific” is someone saying exactly which jacket they want someone to grab for them. Activity # 2 – Specific Immune Response • A specific immune response involves… – Antigens antibodies and • In daily life we might speak of viruses, bacteria, and toxins. However, when reading about the immune system you’ll often come across the words antigen and pathogen. • An antigen is a foreign substance that triggers a reaction from the immune system. Antigens are often found on the surfaces of bacteria and viruses. • A pathogen is a microscopic organism that causes sickness. Hostile bacteria and viruses are examples of pathogens. • Some white blood cells make a specific protein, called an antibody, that will respond to an antigen. Antibodies are released from the white blood cells so that they can seek out intruders and help destroy them. White blood cells produce antibodies at an amazing rate and can release tens of thousands of antibodies per second. • When the Y-shaped antibody finds a matching antigen, it attaches to it. The attached antibodies serve as an appetizing coating for eater cells such as the macrophage (a white blood cell that eats pathogens). • Antibodies also neutralize toxins and viruses, preventing them from infecting new cells. Each branch of the Y-shaped antibody can bind to a specific antigen, so while one branch binds to an antigen on one pathogen cell, the other branch could bind to another cell - in this way pathogens are gathered into larger groups that are easier for macrophages to eat.