Lesson 1: Coordinated Functions of the Nervous, Endocrine, and Reproductive Systems PDF

As you go through this chapter, you will be able to: 1. Identify the parts and functions of the nervous, endocrine, and reproductive systems, 2. Perform an activity that demonstrates the reflex arc, 3. And explain how the positive and the negative feedback mechanisms occur in the nervous a...

As you go through this chapter, you will be able to: 1. Identify the parts and functions of the nervous, endocrine, and reproductive systems, 2. Perform an activity that demonstrates the reflex arc, 3. And explain how the positive and the negative feedback mechanisms occur in the nervous and endocrine systems to maintain homeostasis. THE NERVOUS SYSTEM The Nervous System controls and coordinates all the body functions. This system monitors internal and external stimuli such as touch, smell, sound, blood pressure, and body position. The nervous system is very important in helping to maintain the homeostasis (balance) of the human body. A series of sensory receptors work with the nervous system to provide information about changes in both the internal and external environments. THE CELL OF THE NERVOUS SYSTEM Parts of a Neuron 1. Neuron A neuron is a nerve cell that is the basic building block of the nervous system. Neurons are similar to other cells in the human body in a number of ways, but there is one key difference between neurons and other cells. Neurons are specialized to transmit information throughout the body. 2. Neuroglia The Neuroglia are a group of supportive cells for the neurons. Further, they maintain the myelin sheath, provide nutrient support. Moreover, they also retain homeostasis. It is within the CNS and PNS. Types of the Glial Cells Astrocyte Oligodendrocyte Microglia Ependymal cell Satellite cell and Schwann cell TWO MAJOR PARTS OF NERVOUS SYSTEM 1. Central Nervous System (CNS) 2. Peripheral Nervous System (PNS) TWO MAJOR PARTS OF NERVOUS SYSTEM FLOW CHART The Central Nervous System The central nervous system (CNS) consists of the brain and spinal cord. This body system is responsible for integrating and coordinating the activities of the entire body. Through these physical structures, thought, emotion, and sensation are experienced, and body movements are coordinated. The Brain The brain is an organ that’s made up of a large mass of nerve tissue that’s protected within the skull. It plays a role in just about every major body system. Some of its main functions include: processing sensory information regulating blood pressure and breathing releasing hormones Parts of the Brain according to its position: Forebrain (front) Midbrain (middle) Hindbrain (at the back) The Four Lobes of the Brain Frontal Lobe Temporal Lobe Parietal Lobe Occipital Lobe The Midbrain The midbrain is a portion of the The Major Parts of the Brain brainstem, positioned above the pons, at the very top of the brainstem, directly underneath the cerebellum. This is one of the most important components of the central nervous system (CNS), as all neuronal transmissions that pass through the body, throughout the peripheral nervous system (PNS) to the CNS are relayed must at some point – to and/or from the brain – pass through the midbrain. The Peripheral Nervous System The peripheral nervous system consists of all neurons that exist outside the brain and spinal cord. This includes long nerve fibers as well as ganglia made of neural cell bodies. The peripheral nervous system connects the central nervous system (CNS) to various parts of the body. sensory and motor cranial nerves from the brain sensory and motor nerves from the spinal cord They are categorized as; Cervical (C) Thoracic (T) Lumbar (L) Sacral (S) Coccygeal (C) Two Major Division of Peripheral nervous System The Somatic Nervous System Autonomic Nervous System The Somatic Nervous System The somatic nervous system is the part of the peripheral nervous system that is responsible for carrying motor and sensory information both to and from the central nervous system (CNS). The somatic nervous system contains two major types of neurons: Sensory neurons, also known as afferent neurons, are responsible for carrying information from the body 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 Autonomic Nervous System Autonomic nervous system lies almost entirely outside of the central nervous system and involves two main parts: the craniosacral part (parasympathetic), and the thoracolumbar part (sympathetic). These are sometimes thought of as being opposite to each other, ultimately striking a balance within the body. The parasympathetic is associated with relaxation, digestion, and generally taking it easy. The sympathetic is responsible for the "fight or flight" response. Two Divisions of Autonomic Nervous System Sympathetic Nervous System Parasympathetic Nervous System