Chapter 1 Study Guide Answers PDF

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Chapter 1: An Introduction to the Human Body 1. Define the terms anatomy and physiology. Anatomy: The science of body structures and the relationships among them. Physiology: The science of body functions – how the body parts work Dissection: 2. Define the following levels of structural organization: chemical, cellular, tissue, organ, system and organism. Chemical: The very basic level. Includes atoms, the smallest units of matter that participate in chemical reactions, and molecules (two or more atoms joined together). Cellular: Molecules combine to form cells, the basic structural and functional units of an organism that are composed of chemicals. Examples include: muscle cell, nerve cell, epithelial cell Tissue: groups of cells and materials surround them that work together to perform a particular function. Four basic types of tissue:    

Epithelial Tissue: covers body surfaces, lines hollow organs and cavities, and forms glands. Connective Tissue: connects, supports, and protects body organs while distributing blood vessels to other tissues. Muscular Tissues: Contracts to make body parts move and generates heat. Nervous Tissue: carries information from one part of the body to another through nerve impulses

Organ: Different types of tissues are joined together. Organs are the structures that are composed of two or more different types of tissues; they have specific functions and usually have recognizable shapes. System: Consists of related organs with a common function. Sometimes an organ is part of more than one system (e.g. pancreas is part of both the digestive system and the endocrine system)

Organism: Any living individual. All the parts of the human body functioning together constitute the total organism. 3. Identify the 11 systems of the human body, list representative organs of each system, and describe the major functions of each system. Integumentary System  

Components: Skin and associated structures such as hair, fingernails and toenails, sweat glands, and oil glands Function: protects body; helps regulate body temperature; eliminates some wastes; helps make vitamin D; detects sensations such as touch, pain, warmth, and cold; stores fat and provides insulation

Skeletal System  

Components: Bones and joints of the body and their associated cartilages Function: Support and protects the body; provides surface area for muscle attachments; aids body movements; houses cells that produce blood cells; stores minerals and lipids

Muscular System  

Components: skeletal and muscle tissue – muscle usually attached to bones (other muscle tissues include smooth and cardiac) Function: Participates in body movements, such as walking; maintains posture; produces heat

Nervous System  

Components: Brian, spinal cord, nerves, and special sense organs such as eyes and ears Functions: Generates action potentials (nerve impulses) to regulate body activities; detects changes in bodies internal and external environments, interprets changes and responds by causing muscular contractions or glandular secretions.

Endocrine System

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Components: Hormone- producing glands (pineal gland, hypothalamus, pituitary gland, thymus, thyroid gland, parathyroid gland, adrenal glands, pancreas, ovaries, and testes) and hormone-producing cells in several other organs Functions: regulates body activities by releasing hormones (chemical messengers transported in blood from endocrine gland or tissue to target organ)

Digestive System 

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Components: Organs of gastrointestinal tract, a long tube that includes the mouth, pharynx (throat), esophagus (food tube), stomach, small and large intestines, and anus; also includes accessory organs that assist in digestive processes, such as salivary glands, liver, gallbladder, and pancreas. Function: Achieves physical and chemical breakdown of food; absorbs nutrients; eliminates solid wastes

Lymphatic System 

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Components: Lymphatic fluid and vessels; spleen, thymus, lymph nodes, and tonsils; cells that carry out immune responses (Bcells, T cells, and others) Functions: returns proteins and fluid to blood; carries lipids from gastrointestinal tract to blood; contains sites of maturation and proliferation of B cells and T cells that protect against disease-causing microbes.

Urinary System  

Components: Kidney, ureters, urinary bladder, and urethra Functions: Produces, stores, and eliminates urine; eliminates wastes and regulates volume and chemical composition of blood; helps maintain the acid-base balance of body fluids; maintains body’s mineral balance; helps regulate production of red blood cells.

Cardiovascular System 

Components: Blood, heart, and blood vessels

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Functions: Heart pumps blood through blood vessels; blood carries oxygen and nutrients to cells and carbon dioxide and wastes away from cells and helps regulate acid-base balance, temperature, and water content of body fluids; blood components help defence against disease and repair damaged blood vessels

Respiratory System 

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Components: Lungs and air passageways such as the pharynx (throat), larynx (voice box), trachea (windpipe), and bronchial tubes leading into and out of lungs. Functions: Transfers oxygen from inhaled air to blood and carbon dioxide from blood to inhaled air; helps regulate acid base balance of body fluids; air flowing out of lungs through vocal cords produces sounds

Reproductive System 

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Components: Gonads (testes in males, ovaries in females) and associated organs (uterine tubes or fallopian tubes, uterus, vagina, and mammary glands in females and epididymis, ductus or vas deferens, seminal vesicles, prostate, and penis in males) Functions: Gonads produce gametes (sperm or oocytes) that unite to form a new organism; gonads also release hormones that regulate reproduction and other body processes; associated organs transport and store gametes; mammary glands produce milk.

4. Identify the basic life processes of the human body. a. Metabolism: is the sum of all chemical processes that occur in the body i. Catabolism – a phase of metabolism. The breakdown of complex chemical substances into simpler components ii. Anabolism – a phase of metabolism. The building up of complex chemical substances from smaller, simpler components Example: Digestive processes catabolize (split) proteins in food into amino acids. These amino acids are then used to anabolize (build) new proteins that make up body structures such as muscles and bones.

b. Responsiveness: the bodies ability to detect and respond to changes. (e.g., temperature, squealing noise). Different cells in the body respond to environmental changes in characteristic ways (muscle cells, nerve cells) c. Movement: includes motion of the whole body, individual organs, single cells and even tiny structures inside cells. d. Growth: is an increase in body size that results from an increase in the size of existing cells, an increase in the number of cells, or both. In addition, a tissue sometimes increases in size because the amount of material between cells increases. e. Differentiation: the development of a cell from an unspecialized to a specialized state. i. Stem cells: precursor cells that can divide and give rise to cells that undergo differentiations. (e.g. RBC and WBC arise from the same unspecialized precursor cell in red bone marrow) f. Reproduction: refers either to (1) the formation of new cells for tissue growth, repair, or replacement, or (2) the production of a new individual. The formation of new cells occurs through cell division. The production of a new individual occurs through the fertilization of an ovum by a sperm cell to form a zygote, followed by repeated cell divisions and the differentiation of these cells g. Autopsy: examination of the body and dissection of its internal organs to confirm or determine cause of death. Can uncover disease not detected during life, determine the extent of injuries, and explain how injuries may have contributed to ones death. i. Necropsy: post-mortem (after death)

5. Define the term homeostasis, and explain the effects of stress on homeostasis. a. Homeostasis: is the condition of equilibrium (balance) in the body’s internal environment because of constant interaction of the bodies many regulatory process’ i. If homeostatic imbalance is moderate, disorder or disease can occur and even death if it severe ii. Disruptions of homeostasis come from external and internal stimuli and psychological stresses. When disruption of homeostasis is mild and temporary, responses of body cells

quickly restore balance in the internal environment. If disruption is extreme regulation of homeostasis may fail. b. Body fluids: dilute, water solution that have chemicals that are found inside cells and the area around them. i. Intracellular fluid (ICF): fluid inside of the cells ii. Extracellular fluid (ECF): fluid outside of the cell. I.

Interstitial fluid = internal environment. Fills space between tissue cells – because it surrounds all body cells, it is called the bodys internal environment II. Blood plasma: within blood III. Lymph: within lymphatic vessels IV. Cerebrospinal fluid: around the brain and spinal cord V. Synovial fluid: in joints VI. Aqueous humour: fluid in the eye VII. Vitreous body: fluid in eye 6. Describe the components of a feedback system: is a cycle of events in which the body’s condition is monitored, evaluated, changed, re-monitored, and reevaluated.  Controlled conditions: There are different monitored variables like temperature, BP, sugar  Feedback systems include three components: (Feedback loop) o Receptors monitor changes in a controlled condition and send input to a control center (afferent pathway) o The control center sets the value (set point) at which a controlled condition should be maintained, evaluates the input it receives from receptors (efferent pathway), and generates output commands when needed. o Effectors receive output from the control center and produce a response (effect) that alters the controlled condition.  Receptor o Monitor changes in the controlled condition and send input to a control center. The pathway the impulse travels is called afferent (toward) since the information is taken towards the control center.  Control Center

o Sets the range values within which a controlled condition should be maintained, evaluates input received from receptors and produces a command when needed. o Usually the output occurs as nerve impulses or hormones. This pathway is called efferent pathway (away from) the control center o Ex. Brain and skin  Effector o Body structure that receives output from the control center and produced a response of effect, in the end changes the controlled condition. o Ex. When temperature drops, your brain (control center) sends impulse (output) to muscles (effectors). This results in shivering which generates heat and increases body temperature. a. Control of homeostasis; nerve impulses and hormones i. The nervous and endocrine systems acting together or separately regulate homeostasis. The nervous system detects body changes and sends nerve impulses to counteract changes in controlled conditions. The endocrine system regulates homeostasis by secreting hormones 7. Compare the operation of negative and positive feedback systems.  Positive feedback system: If a response enhances the original stimulus. Tends to strengthen or reinforce changes in one of the bodies-controlled conditions o Still provides commands to an effector, but effector produces response that add or reinforce the initial change in controlled condition. o Ex. Birth of a baby: labour  the cervix of the uterus is stretched (stimulus), and stretch-sensitive nerve cells in the cervix (receptors) send nerve impulses (input) to the brain (control center). The brain responds by releasing oxytocin (output), which stimulates the uterus (effector) to contract more forcefully (response). Movement of the fetus further stretches the cervix, more oxytocin is released and even more forceful contractions occur. The cycle is broken with the birth of the baby/placenta. o Ex. When severe blood loss occurs – BP falls  heart pumps slow

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Negative feedback system: Response reverses the original stimulus. The response stops when a controlled condition returns to its normal state. o Ex. Regulation of BP: If a stimulus causes BP (controlled condition) to rise, baroreceptors (pressure-sensitive nerve cells – receptors) in blood vessels send impulses (input) to the brain (controlled center). The brain sends impulses (output) to the heart (effector). As a result, heart rate decreases (response) and blood pressure decreases to normal (restoration of homeostasis). 8. Explain the relationship between homeostasis and disease. Disruptions of homeostasis – homeostatic imbalances – can lead to disorders, diseases, and even death. A disorder is a general term for any abnormality of structure or function. A disease is an illness with a definite set of signs and symptoms. 9. Describe the anatomical position, and compare common and anatomical terms used to describe various regions of the human body. Anatomical position = stands erect facing the observer with the head level and eyes facing forward. Lower limbs are parallel and the feet are flat on the floor and directed forward – palms facing forward.  

Prone: lying face down Supine: lying face up

Regional names:     

Head: Skull [encloses brain] + Face [Front Portion] Neck: Supports Head and Attaches to Trunk Trunk: Chest + abdomen + pelvis U-Limbs: attaches to trunk – arms L-Limbs: attaches to trunk – Legs + Butt

Directional terms: words that describe position in relation to another    

Superior/Cephalic/Cranial – toward head Inferior/Caudal – away from head Anterior/Ventral – toward front Posterior/Dorsal – toward back

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Medial – toward midline Lateral - away from midline Intermediate – between two structures Ipsilateral – same side of body as another structure Contralateral – opposite side of body from another structure Proximal – near attachment of a limb to trunk Distal – away from attachment of a limb to trunk Superficial/External – toward surface Deep/Internal – away from surface

10. Define the terms describing directions and anatomical planes used in association with the human body. Planes and Sections (pg. 16) Planes: imaginary flat surfaces that pass through body      

Sagittal – Vertical, divides body into L/R Midsagittal/Median – Through midline of body or organ (equal L/R) Parasagittal – divide body in unequal L and R Midline – Separates body into equal L and R Frontal/Coronal – divides body into anterior and posterior Transverse/Cross-sectional/Horizontal – divides body into superior (upper) and inferior (lower)

11. List, by name and location, the principal body cavities and the organs contained within them. Section: Cut of a body or organ along one of the above planes Body Cavities (pg. 17,18) a. Cranial Cavity - cranial bones + brain b. Vertebral Canal - vertebral column = spinal cord + beginnings of spinal nerves c. Thoracic Cavity - chest cavity; pleural cavity + pericardial cavity + mediastinum i. Pleural cavity – potential space between the layers of the pleura that surrounds the lung ii. Pericardial cavity – potential space between the layers of the pericardium that surrounds the heart iii. Mediastinum - central position thoracic cavity between the lungs; extends from sternum to vertebral column and from first rib to diaphragm; contains heart, thymus, esophagus, trachea, and several large blood vessels d. Abdominopelvic cavity – abdominal + pelvic cavity i. Abdominal cavity – stomach + spleen + liver + gallbladder + small intestine + most of large intestine; the serous membrane of the abdominal cavity is the peritoneum ii. Pelvic cavity – urinary bladder + portions of the large intestine + internal organs of reproduction.

Meninges: 3x protective tissues + shock absorbing fluid Diaphragm: Separates thoracic from abdominopelvic cavity Viscera: Organs inside thoracic & abdominopelvic cavities Nasal Cavity: Mary cavity, synovial cavity & orbital cavity (eyes) Medical Imaging (pg. 21-24) 1.

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Radiography: X-ray = white picture indicates density = structural image a. Mammography: breast tissue examination b. Bone densitometry: bone density examination c. Angiography: blood vessels [can show blockage] d. Intravenous urogram: kidney examination e. Barium Contrast X-Ray: Colon examination MRI: High magnetic field, causes protons to arrange themselves = shows cellular chemistry [done for soft tissues to detect tumors Computed Tomography [CT]: X-ray for section of body as a transverse section = differentiates tissues based on densities = accurate structure Ultrasound Scanning: High frequency waves that reflect off of structures to give an image Coronary [Cardiac] Computed Tomography Angiography Scan [CCTA]: Iodine-medium is injected, then x-rays trace its movement = gives image

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Positron Emission Tomography [PET]: Positron injected in blood, taken up by tissues as it collides with electrons = produces gamma rays = shows activity of body 7. Endoscopy: Visual examination vis camera 8. Radionuclide Scanning: radioactive substance injected and carried to tissues = emits gamma rays = intense colours shows MORE activity 9. Single Photon-Emission CT scanning [SPECT]: Specialized type of radionuclide scanning especially for brain, heart, lungs and liver....