Transcript Helper T
Body Systems that Regulate Body Functions Nervous System What is the function of the nervous system? Overview of a vertebrate nervous system Structure of a vertebrate neuron What are the functions of: dendrites, axons, synapses? The main parts of the human brain Homeostasis Thinking, memory, learning “Master Gland” Balance, Movement Heart rate & Breathing REVIEW Create a flow map to explain the series of events that happen from when you hear a loud noise to when you turn your head. Receptors in ear receive sound information Hormones & The Endocrine System What is the function of the endocrine system? Definitions • Hormones – Chemical messages – Regulate activity of other cells – Help maintain homeostasis • Endocrine glands – Secrete hormones Endocrine System Types of Hormones • Protein hormones – Polar – Can they go through the cell membrane? • Steroid hormones – Made from cholesterol – Can they go through the cell membrane? Hormones are Chemical Signals How does a protein hormone regulate a cell? How does a steroid hormone regulate a cell? Selected Hormones & Glands How can hormones maintain homeostasis? Negative Feedback Adrenal Glands & Stress • “Fight or Flight” – Immediate Stress – Epinephrine & Norepinephrine – hormones – Prepare body for emergency action • Increase heart rate • Increase blood glucose level • Long-term Stress – – – – Cortisol & Aldosterone – hormones Makes more energy available to body Suppresses immune system Increases blood pressure Time for a yoga class? Review Create a Thinking Map of your choice to summarize what hormones do and how they work. Immune System What is the function of the immune system? First Line of Defense • Blocking germs from getting inside in the first place – Skin – Mucous membranes – Low pH in stomach Second Line of Defense • Attacks invaders when they get in • Not specific – kills all cells that aren’t supposed to be there Phagocytotic WBC Fever Inflammation Third Line of Defense • Specific – attacks a specific invader (antigen) – Examples – cold, flu, measels • Antigens – cause a specific immune response • Made up of white blood cells (lymphocytes) – B cells – T cells Helper T-Cells 1. 2. 3. 4. A macrophage (phagocytotic WBC) eats an invader It wears surface proteins of the bacteria The Helper T-Cell that can fight this infection recognizes the surface protein The Helper T-Cell organizes B Cells and Cytotoxic T-Cells ** Helper T-Cells are Coordinators ** Cytotoxic T-Cells Kill infected cells by causing them to lyse (pop open) B Cells Make antibodies; Antibodies prevent invader from infecting new cells Lock and key fit (Invader) Memory & Immunity Antibodies and Memory Cells “remember” an infection so you only get sick once. HIV attacks Helper T-Cells Very low Helper T Cell Can’t fight infections Vaccines • Cause immunity without sickness • Cause specific immune response; build up of antibodies • Examples – Killed microbes – Parts of microbes – Weakened microbes Review Think of an analogy to compare and contrast the non-specific and specific immune responses. Create a Thinking Map to summarize the function of the Immune System.