Biol1593 sw6 Module 1 TRU BIOL 1593 PDF

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BIOL 1593: Anatomy and Physiology I M1-Module 1: An Introduction to the Human BodyIntroductionThe human body is a complex single structure made up of billions of smaller structures that work together to accomplish specific functions necessary to sustain life. The purpose of this module is to introdu...

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BIOL 1593: Anatomy and Physiology I

M1-17

Module 1: An Introduction to the Human Body Introduction The human body is a complex single structure made up of billions of smaller structures that work together to accomplish specific functions necessary to sustain life. The purpose of this module is to introduce two scientific disciplines that study the human body (anatomy and physiology); examine how the body constantly regulates its internal environment; consider the interactions between individual body systems; and establish a basic, scientifically acknowledged vocabulary for understanding the human body.

Objectives Overview 1. Define anatomy and physiology. 2. Describe the different levels of organization in the human body. 3. List and describe the major body systems, and state the general function of each. 4. List and describe the major characteristics of life (life processes). 5. Define homeostasis, and explain its importance to survival. 6. Define a feedback system, and list the component parts of a feedback loop. 7. Define, explain, and give examples of positive and negative feedback loops. 8. Define disease, symptom, and sign, and relate each to homeostatic imbalance. 9. Describe the anatomical position by using the descriptive and directional terms that refer to body structures, surfaces, and regions. 10. Identify the planes of reference used to depict the structural arrangement of the human body. 11. Identify the body cavities, and list the organs found within each. 12. List the regions of the body and the localized areas within each region. To accomplish these objectives, in your textbook Introduction to the Human Body (11th ed.), read carefully through Chapter 1: “Organization of the Human Body.” After you finish, read the explanatory material in this module, complete the self-test, and grade yourself. Do not send your grade to your Open Learning Faculty Member for evaluation; instead, use it to identify any areas you may need to review, or to determine whether to ask your Open Learning Faculty Member for assistance.

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Module 1: An Introduction to the Human Body

Important Note: In the following “Objective” sections, the page, figure, and table numbers refer to pages, figures, and tables in your textbook.

Objective 1: Define anatomy and physiology. See Page 1 Anatomy is defined as the study of structure and the relationships among structures. Physiology is the study of how body structures function.

Objective 2: Describe the different levels of organization in the human body. See Pages 1–3; Fig. 1.1 The chemical level includes atoms—the smallest units of matter that participate in chemical reactions—and molecules, which are two or more atoms joined together. Cells are the basic structural and functional units of an organism. Tissues consist of groups of similarly specialized cells and the substances surrounding them that usually arise from a common ancestor and perform certain special functions. Organs are structures of definite form that have specific functions, and are composed of two or more different tissues. Systems consist of related organs that have a common function. The human organism is a collection of structurally and functionally integrated systems.

Objective 3: List and describe the major body systems, and state the general function of each. See Table 1.1 The systems of the human body are the integumentary, skeletal, muscular, nervous, endocrine, cardiovascular, lymphatic, respiratory, digestive, urinary, and reproductive.

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BIOL 1593: Anatomy and Physiology I

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Objective 4: List and describe the major characteristics of life (life processes) See Page 6 All living things have certain characteristics that distinguish them from nonliving things. The life processes of humans include metabolism, responsiveness, movement, growth, differentiation, and reproduction. Metabolism is the sum of all chemical processes that occur in the body, including catabolism and anabolism. Responsiveness is the ability to detect and respond to changes in the external or internal environment. Movement includes the motion of the whole body, individual organs, single cells, or even organelles inside the cells. Growth refers to an increase in size and complexity due to an increase in the number of cells, size of cells, or both. Differentiation is the change in a cell from an unspecialized state to a specialized state. Reproduction refers either to the formation of new cells for growth, repair, or replacement; or the production of a new individual.

Objective 5: Define homeostasis, and explain its importance to survival. See Page 7 Homeostasis is a condition of equilibrium in the body’s internal environment, which is produced by the ceaseless interplay of all the body’s regulatory processes. Homeostasis is regulated by the nervous system and endocrine system, acting together or independently. The nervous system detects changes and sends nerve impulses to counteract a disruption. The endocrine system regulates homeostasis by secreting hormones. Nerve impulses cause rapid changes, whereas hormones usually work more slowly.

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Module 1: An Introduction to the Human Body

Objective 6: Define a feedback system, and list the component parts of a feedback loop. See Pages 7–8; Fig. 1.2 A feedback system is a cycle of events through which information about the status of a condition is continually monitored and fed back (reported) to a central control region. Any disruption that changes a controlled condition is called a stimulus. A feedback system consists of the three following basic components: 1. A receptor that monitors changes in a controlled condition and sends input as nerve impulses or chemical signals to a control centre 2. The control centre that sets the range of values for the maintenance of a controlled condition, evaluates the input received from the receptors, and generates output commands when needed 3. An effector (a body structure) that receives output from the control centre and produces a response or effect that changes the controlled condition

Objective 7: Define, explain, and give examples of positive and negative feedback loops. See Pages 8–9; Figs. 1.3, 1.4 If a response reverses the original stimulus, the system is a negative feedback system, for example, the homeostasis of blood pressure (BP). If a response enhances the original stimulus, the system is a positive feedback system, for example, normal childbirth.

Objective 8: Define disease, symptom, and sign, and relate each to homeostatic imbalance. See Page 9 A disruption of homeostasis can lead to disease and death. Disorder is a general term for any abnormality of function. Disease is a more specific term for an illness characterized by a recognizable set of signs and symptoms. Symptoms are subjective changes in body functions that are not apparent to an observer, for example, headache or nausea.

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BIOL 1593: Anatomy and Physiology I

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Signs are objective changes that a clinician can observe and measure, for example, fever or rash.

Objective 9: Describe the anatomical position by using the descriptive and directional terms that refer to body structures, surfaces, and regions. See Pages 10–12; Figs. 1.5, 1.6 The anatomical position is a standardized method for observing or imaging the body, which allows precise and consistent anatomical references. In the anatomical position, the subject stands erect facing the observer; her/his upper extremities (arms) are placed at their side; the palms of their hands are turned forward; and their feet are flat on the floor.

Objective 10: Identify the planes of reference used to depict the structural arrangement of the human body. See Pages 12–14; Figs. 1.7, 1.8 Planes are imaginary flat surfaces that are used to divide the body or organs into definite areas. The principal planes include the midsagittal (medial) and parasagittal, frontal (coronal), transverse (cross-sectional or horizontal), and oblique. Sections are the flat surfaces that are created by cutting through body structures. These sections are named according to the plane on which the cut is made, for example, transverse, frontal, and midsagittal. Directional terms are used to precisely locate one part of the body relative to another, and to reduce the length of explanations about these relationships. Commonly used directional terms are dorsal, superior, medial, ventral, inferior, lateral, and proximal.

Objective 11: Identify the body cavities and list the organs found within each. See Pages 15–17; Figs. 1.9, 1.10 Body cavities are spaces within the body that help to protect, separate, and support the internal organs. Dorsal Body Cavity The dorsal body cavity is located near the dorsal surface of the body; it has two subdivisions—the cranial cavity and the vertebral canal.

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Module 1: An Introduction to the Human Body

The cranial cavity is formed by the cranial bones, which surround and protect the brain. The vertebral (spinal) canal is formed by the bones of the vertebral column, which surround and protect the spinal cord. Ventral Body Cavity The diaphragm subdivides the ventral cavity into an upper thoracic cavity and a lower abdominopelvic cavity. The thoracic cavity contains two pleural cavities and the mediastinum, which includes the pericardial cavity. The pleural cavities enclose the lungs, and the pericardial cavity surrounds the heart. The mediastinum is a broad, median partition between the lungs that extends from the sternum to the vertebral column. It contains everything in the thoracic cavity except the lungs. The abdominopelvic cavity is divided into a superior abdominal and an inferior pelvic cavity. Note: The terms dorsal body cavity and ventral body cavity do not appear in your textbook, but they are commonly used.

Objective 12: List the regions of the body and the localized areas within each region. See Pages 17–18; Figs. 1.11, 1.12 To easily describe the location of the organs, the abdominopelvic cavity can be divided into nine regions by drawing four imaginary lines. In clinical studies, to locate the site of an abdominopelvic abnormality, the abdominopelvic cavity can be divided into quadrants by drawing imaginary horizontal and vertical lines through the umbilicus.

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