Lesson 2: The Nervous and Endocrine Systems PDF

Lesson 2: The Nervous and Endocrine Systems Prepared by: Livien U. Ciabal,PhD, RGC, RPm  The Nervous and Endocrine Systems A. The Nervous System B. The Endocrine System Intended Learning Objectives 1. Describe the functions o...

Lesson 2: The Nervous and Endocrine Systems Prepared by: Livien U. Ciabal,PhD, RGC, RPm  The Nervous and Endocrine Systems A. The Nervous System B. The Endocrine System Intended Learning Objectives 1. Describe the functions of the nervous system’s main divisions, and identify the three main types of neurons. 2. Describe the nature and functions of the endocrine system and its interaction with the nervous system.  The Nervous Systems Nervous System the body’s speedy, electrochemical communication network, consisting of all the nerve cells of the peripheral and central nervous systems. Central Nervous System (CNS) the brain and spinal cord. Peripheral Nervous System (PNS) the sensory and motor neurons that connect the central nervous system (CNS) to the rest of the body. Nerves bundled axons that form neural “cables” connecting the central nervous system with muscles, glands, and sense organs. The Nervous System  The Nervous System Information travels in the nervous system through three types of neurons. Sensory neurons Motor neurons Interneurons. The Peripheral Nervous System  The Peripheral Nervous System Somatic Nervous System(SNS) Autonomic Nervous System (ANS) The Peripheral Nervous System Somatic Nervous System(SNS) enables voluntary control of our skeletal muscles. The term "somatic nervous system" is drawn from the Greek word soma, which means "body," which is appropriate considering it is this system that transmits the information to and from the CNS to the rest of the body. The Peripheral Nervous System Somatic Nervous System(SNS): contains two major types of neurons: – Sensory neurons, also known as afferent neurons, are responsible for carrying information from the nerves to the CNS. – Motor neurons, also known as efferent neurons, are responsible for carrying information from the brain and spinal cord to muscle fibers throughout the body. The Peripheral Nervous System Autonomic Nervous System (ANS) controls our glands and the muscles of our internal organs, influencing such functions as glandular activity, heartbeat, and digestion. Like an automatic pilot, this system may be consciously overridden, but usually operates on its own (autonomously). The Peripheral Nervous System Autonomic Nervous System(ANS) is the part of the nervous system that supplies the internal organs, including the blood vessels, stomach, intestine, liver, kidneys, bladder, genitals, lungs, pupils, heart, and sweat, salivary, and digestive glands. serves two important, basic functions or divided into two main divisions : The sympathetic nervous system arouses and expends energy. The fight or flight response The parasympathetic nervous system will produce the opposite effects, conserving energy as it calms you by decreasing your heartbeat, lowering your blood sugar, and so forth. rouses and expends energy. The Peripheral Nervous System Autonomic Nervous System(ANS) The sympathetic nervous system : Prepares the body for stressful or emergency situations— fight or flight Thus, the sympathetic division increases heart rate and the force of heart contractions and widens (dilates) the airways to make breathing easier. It causes the body to release stored energy. Muscular strength is increased. The Peripheral Nervous System Autonomic Nervous System(ANS) The parasympathetic nervous system: Controls body process during ordinary situations. Generally, the parasympathetic division conserves and restores. It slows the heart rate and decreases blood pressure. The Peripheral Nervous System The Peripheral Nervous System The sympathetic and parasympathetic nervous systems The sympathetic and make an opponent process system. parasympathetic nervous systems together make an opponent process system.  The Central Nervous Systems The central nervous system (CNS) controls most functions of the body and mind. It consists of two parts: - the brain and - the spinal cord.  The Central Nervous Systems The CNS consists of the brain and spinal cord. The brain can be divided into four main lobes: temporal, parietal, occipital and frontal. The Central Nervous Systems The Brain The brain’s neurons cluster into work groups called neural networks. * As in FIGURE 3, each layer’s cells connect with various cells in the neural network’s next layer. The Central Nervous Systems The Central Nervous Systems The Spinal Cord The spinal cord, is a two-way information highway connecting the peripheral nervous system and the brain. Ascending neural fibers send up sensory information, and descending fibers send back motor - control information. * The Central Nervous Systems The Spinal Cord The spinal cord is attached to the underside of the medulla oblongata, and is organized to serve four distinct tasks: 1. to convey (mainly sensory) information to the brain; 2. to carry information generated in the brain to peripheral targets like skeletal muscles; 3. to control nearby organs via the autonomic nervous system; 4. to enable sensorimotor functions to control posture and other fundamental movements.  Sensory neurons connect to the spinal cord dorsally, or in your back. Motor neurons connect in the anterior of the spinal cord, or in the front.  The dendrites of neurons contribute significantly to the complexity of the neural network. The neural chain, also known as the reflex arc, can be described graphically Figure 4 The Central Nervous Systems  The Endocrine Systems The endocrine system is responsible for regulating a range of bodily functions through the release of hormones.  The Endocrine Systems Hormones are secreted by the glands of the endocrine system, traveling through the bloodstream to various organs and tissues in the body. The hormones then tell these organs and tissues what to do or how to function.  The Endocrine Systems Some examples of bodily functions that are controlled by the endocrine system include: metabolism growth and development sexual function and reproduction heart rate blood pressure appetite sleeping and waking cycles body temperature  The Endocrine Systems Figure 5.  The Endocrine Systems Endocrine system organs The endocrine system is made up of a complex network of glands, which are organs that secrete substances.  The Endocrine Systems The glands of the endocrine system include: ▪ Hypothalamus ▪ Pituitary ▪ Pineal ▪ Thyroid ▪ Parathyroid ▪ Thymus ▪ Adrenal ▪ Pancreas  The Endocrine Systems Hypothalamus. While some people don’t consider it a gland, the hypothalamus produces multiple sleep-wake cycles body temperature, and appetite. also regulate the function of other endocrine glands.  The Endocrine Systems Pituitary. The pituitary gland is located below the hypothalamus. The hormones it produces affect growth and reproduction. They can also control the function of other endocrine glands.  The Endocrine Systems Pituitary. The pituitary releases certain hormones. One is a growth hormone that stimulates physical development. Another, oxytocin, enables contractions associated with birthing, milk flow during nursing, and orgasm. Oxytocin also promotes pair bonding, group cohesion, and social trust The Endocrine Systems Pineal. This gland is found in the middle of your brain. It’s important for your sleep-wake cycles. The Endocrine Systems Thyroid. The thyroid gland is located in the front part of your neck. It’s very important for metabolism. The Endocrine Systems Parathyroid. Also located in the front of your neck important for maintaining control of calcium levels in your bones and blood. The Endocrine Systems Thymus. Located in the upper torso, the thymus is active until puberty and produces hormones important for the development of a type of white blood cell called a T cell. The Endocrine Systems Adrenal. One adrenal gland can be found on top of each kidney. These glands produce hormones important for regulating functions such as blood pressure, heart rate, and stress response. The Endocrine Systems Pancreas. The pancreas is located in your abdomen behind your stomach. Its endocrine function involves controlling blood sugar levels.  The Endocrine Systems Some endocrine glands also have non- endocrine functions. For example, the ovaries and testes produce hormones, but they also have the non-endocrine function of producing eggs and sperm, respectively. ▪ Ovaries secrete estrogen, promoting ovulation and female sex characteristics. ▪ Testes release androgens, promoting sperm production and male sex characteristics. The Endocrine Systems and nervous system The endocrine system and nervous system are therefore close relatives: Both produce molecules that act on receptors elsewhere. Like many relatives, they also differ. The speedy nervous system zips messages from eyes to brain to hand in a fraction of a second. Endocrine System Endocrine system hormones Hormones are the chemicals the endocrine system uses to send messages to organs and tissue throughout the body. Once released into the bloodstream, they travel to their target organ or tissue, which has receptors that recognize and react to the hormone. Below are some examples of hormones that are produced by the endocrine system. Below are some examples of hormones that are produced by the endocrine system. Below are some examples of hormones that are produced by the endocrine system. Conditions that can affect the endocrine system Hyperthyroidism Hyperthyroidism happens when your thyroid gland makes more thyroid hormone than necessary. This can be caused by a range of things, including autoimmune conditions. Some common symptoms of hyperthyroidism include: ▪ fatigue ▪ nervousness ▪ weight loss ▪ diarrhea ▪ issues tolerating heat ▪ fast heart rate ▪ trouble sleeping Conditions that can affect the endocrine system Treatment depends on how severe the condition is, as well as its underlying cause. Options include medications, radioiodine therapy, or surgery. Graves disease is an autoimmune disorder and common form of hyperthyroidism. In people with Graves disease, the immune system attacks the thyroid, which causes it to produce more thyroid hormone than normal. Hypothyroidism Conditions that can affect the endocrine system Hypothyroidism Hypothyroidism occurs when your thyroid doesn’t produce enough thyroid hormone. Like hyperthyroidism, it has many potential causes. Some common symptoms of hypothyroidism include: ▪ fatigue ▪ weight gain ▪ constipation ▪ issues tolerating the cold ▪ dry skin and hair ▪ slow heart rate ▪ irregular periods ▪ fertility issues Conditions that can affect the endocrine system Hypothyroidism Treatment of hypothyroidism involves supplementing your thyroid hormone with medication. Conditions that can affect the endocrine system Cushing syndrome Cushing syndrome happens due to high levels of the hormone cortisol. Common symptoms of Cushing syndrome include: ▪ weight gain ▪ fatty deposits in the face, midsection, or shoulders ▪ stretch marks, particularly on the arms, thighs, and abdomen ▪ slow healing of cuts, scrapes, and insect bites ▪ thin skin that bruises easily ▪ irregular periods ▪ decreased sex drive and fertility in males Treatment depends on the cause of the condition and can include medications, radiation therapy, or surgery. Conditions that can affect the endocrine system Addison disease Addison disease happens when your adrenal glands don’t produce enough cortisol or aldosterone. Some symptoms of Addison disease include: ▪ fatigue ▪ weight loss ▪ abdominal pain ▪ low blood sugar ▪ nausea or vomiting ▪ diarrhea ▪ irritability ▪ a craving for salt or salty foods ▪ irregular periods Treatment of Addison disease involves taking medications that help to replace the hormones that your body isn’t producing enough of. Conditions that can affect the endocrine system Diabetes Diabetes refers to a condition in which your blood sugar levels aren’t regulated properly. People with diabetes have too much glucose in their blood (high blood sugar). There are two types of diabetes: type 1 diabetes and type 2 diabetes. Some common symptoms of diabetes include: ▪ fatigue ▪ weight loss ▪ increased hunger or thirst ▪ frequent urge to urinate ▪ irritability ▪ frequent infections Treatment for diabetes can include blood sugar monitoring, insulin therapy, and medications. Lifestyle changes, such as getting regular exercise and eating a balanced diet, can also help. Learning Engagement #2 Learning engagement #4 Learning engagement #2 Have students research disorders of the endocrine system, including diabetes, abnormal growth, and hypo- and hyperthyroidism. Focus on the following questions: What physical problems do these disorders cause? What emotional problems do these disorders cause? What treatments are available for these disorders?  End