Cell Bio Neoplasia Past Paper Spring 2025 PDF

Cellular Biology, Injury, Adaptations, and Maladaptive Changes MARY L ATIMER, PHD MNL [email protected] Functional Components of the Cell Membranes Cell membrane ◦ Lipids ◦ Phospholipids (amphipathic) ◦ Cholesterol (hydrophobic) ◦ Proteins (integral and surface) Membranous barriers in organelles ...

Cellular Biology, Injury, Adaptations, and Maladaptive Changes MARY L ATIMER, PHD MNL [email protected] Functional Components of the Cell Membranes Cell membrane ◦ Lipids ◦ Phospholipids (amphipathic) ◦ Cholesterol (hydrophobic) ◦ Proteins (integral and surface) Membranous barriers in organelles Cell Membrane Components Lipid bilayer—the basic fluid structure of the membrane and serves as a semipermeable barrier. ◦ Phospholipids with a hydrophilic head and a hydrophobic tail Integral proteins span the entire lipid bilayer. ◦ Ion channels Peripheral proteins are bound to one or the other side of the membrane. Cell Membrane Function Provides receptors for hormones and other biologically active substances Participates in the electrical events that occur in nerve and muscle cells Aids in the regulation of cell growth and proliferation Question #1 Is the following statement true or false? The cell membrane is made up only of lipids and cholesterol molecules. Answer to Question #1 False Rationale: The membrane is made up of lipids and cholesterol, but it is also composed of proteins. Movement across the cell membrane  Transport Mechanisms #1 Passive transport ◦ Diffusion ◦ Osmosis  Transport Mechanisms #2 Facilitated transport  Transport Mechanisms #3 Active transport Integration of Cell Function Cell Communication  Autocrine Signaling Autocrine signaling occurs when a cell releases a chemical into the extracellular fluid that affects its own activity. COPYRIGHT © 2016 F.A. DAVIS COMPANY  Paracrine Signaling Paracrine signaling acts on nearby cells. COPYRIGHT © 2016 F.A. DAVIS COMPANY  Endocrine Signaling Endocrine signaling relies on hormones carried in the bloodstream to cells throughout the body. COPYRIGHT © 2016 F.A. DAVIS COMPANY  Synaptic Signaling Synaptic signaling occurs in the nervous system, where neurotransmitters act only on adjacent nerve cells. COPYRIGHT © 2016 F.A. DAVIS COMPANY Cell Metabolism and Energy Sources Processes by which fats, proteins, and carbohydrates from the foods we eat are converted into energy in the form of ATP Metabolism ◦ Catabolism consists of breaking down stored nutrients and body tissues to produce energy. ◦ Aerobic and anaerobic production of ATP ◦ Anabolism is a constructive process in which more complex molecules are formed from simpler ones. Respiration Series of metabolic processes that transforms fuel molecules into energy and waste products Aerobic ◦ Produces ATP using oxygen Anaerobic ◦ Produces ATP without using oxygen Body Tissues Organization of Cells into Tissues Cells with similar embryonic origin or function are often organized into larger functional units called tissues. ◦ These tissues associate with other, dissimilar tissues to form organs of the body. Four types of tissue. ◦ Epithelial ◦ Connective ◦ Neural ◦ Muscle Epithelia l Tissue Forms sheets that function to: ◦ Cover the body’s outer surface ◦ Line internal surfaces ◦ Form glandular tissue Attaches to a basement membrane Is avascular Muscle Tissue Contains actin and myosin filaments Contracts and provides: ◦ Locomotion and movement of skeletal structures ◦ Pumping blood through the heart ◦ Contraction of blood vessels and visceral organs Types ◦ Cardiac, smooth, skeletal Question #2 Which of the following tissues contains actin and myosin? A. Epithelial B. Connective C. Muscle D. Neural Answer to Question #2 Which of the following tissues contains actin and myosin? A. Epithelial B. Connective C. Muscle D. Neural Cellular Stress and Injury  Cellular Response to Stress Atrophy Hypertrophy Hyperplasia Metaplasia Dysplasia Ischemia Atrophy = Decreased Cell Size Example: Cerebral Atrophy Cerebral Atrophy Pathophysiology Clinical manifestations  Cerebral Atrophy Pathophysiology #1 Reduction in size of the cells in the cerebrum of the brain Progressive reduction in the size of the neurons Result of ◦Reduced stimulation ◦Injury Cerebral Atrophy Clinical Manifestations Focal ◦Localized to a particular region Global ◦Affecting the entire brain Hypertrophy = Increase in Cell Size Example: Cardiac Hypertrophy Cardiac Hypertrophy Pathophysiology Clinical manifestations  Cardiac Hypertrophy Pathophysiology Increased cardiac muscle mass Etiology ◦Excessive cardiac workload ◦Increased functional demand ◦Inherited genetic trait Cardiac Hypertrophy Pathophysiology Categories Primary ◦Inherited non–sex-linked genetic trait Secondary ◦Due to an underlying condition increasing left ventricular workload ◦Increase in left ventricular muscle mass results from an increase in myocardial cell size Cardiac Hypertrophy Clinical Manifestations Variable ◦Mild to severe Shortness of breath Chest pain Syncope (fainting) Impaired cardiac function Hyperplasia = Increase in the Number of Cells (Increases Tissue Mass) Example: Acromegaly Acromegaly Pathophysiology Clinical manifestations  Acromegaly Pathophysiology Condition of cellular hyperplasia Results from excessive hormonal stimulation ◦ Pituitary growth hormone ◦ Liver insulin-like growth factor 1 (IGF-1) Acromegaly Pathophysiology Leads to excessive growth ◦Bones ◦Cartilage ◦Soft tissues ◦Organs Occurs after epiphyseal plate closure Acromegaly Clinical Manifestations Soft tissue swelling Altered facial features Pain and numbness in hands Voice deepening Snoring Skin changes Altered reproductive function Acromegaly Clinical Manifestations Replaced by Another Type of Cell Dysplasia = disordered cells, cells that have lost normal architectural arrangement Example: Cervical Metaplasia and Dysplasia Cervical Metaplasia and Dysplasia  METAPLASIA  DYSPLASIA Cervical Metaplasia and Dysplasia Pathophysiology Clinical manifestations Cervical Metaplasia and Dysplasia Pathophysiology Cellular adaptation of the squamous and columnar epithelial cells in the transformation zone of the cervix Cervical Metaplasia and Dysplasia Clinical Manifestations No signs and symptoms Risk factors ◦ Early onset sexual activity ◦ Multiple partners (>3) ◦ Exposure to human papillomavirus (HPV) ◦ Smoking Ischemia – loss of oxygen Any tissue that sustains prolonged ischemia is susceptible to infarction, but individual cell types have different tolerance levels. Example: brain 6 minutes Example: heart 20 minutes Example: skeletal muscle many hours Ischemic Stroke Pathophysiology Clinical manifestations Ischemic Stroke Pathophysiology Condition of cellular ischemia in the brain Results from loss of blood flow secondary to ◦ Clot Ischemic Stroke Clinical Manifestations  Cellular Injury and Death Mechanisms of death ◦ Apoptosis ◦ Necrosis Causes of injury ◦ Physical ◦ Mechanical ◦ Thermal ◦ Chemical  Environmental Toxin Injury and Cardiovascular Disease Pathophysiology Clinical manifestations Environmental Toxin Injury and Cardiovascular Disease Pathophysiology Exposure to environmental chemicals leads to cardiovascular cell injury. Airborne particulate matter causes oxidative damage and inflammation in heart and blood vessel cells. Additive factor to cardiovascular disease. Environmental Toxin Injury and Cardiovascular Disease Clinical Manifestations Aortic aneurysm Coronary heart disease Acute myeloid leukemia Periodontitis Cancer Pneumonia Cataract Stroke Chronic lung disease Sudden infant death Question #3 Cardiac Hypertrophy has both primary and secondary causes. An example of a primary cause is which of the following? A) Increased Left Ventricular Work Load B) Increased Left Ventricular Mass (Hypertrophy) C) Inherited Traits COPYRIGHT © 2016 F.A. DAVIS COMPANY Answer to Question #3 Cardiac Hypertrophy has both primary and secondary causes. An example of a primary cause is which of the following? A) Increased Left Ventricular Workload B) Increased Left Ventricular Mass (Hypertrophy) C) Inherited Traits COPYRIGHT © 2016 F.A. DAVIS COMPANY Question #4 Which of the following best describes the cellular adaptation seen in Acromegaly? A. Atrophy B. Hypertrophy C. Hyperplasia D. Metaplasia E. Dysplasia Answer to Question #4 Which of the following best describes the cellular adaptation seen in Acromegaly? A. Atrophy B. Hypertrophy C. Hyperplasia D. Metaplasia E. Dysplasia Cellular Adaptation Benign and Malignant Neoplasms The Impact of Cancer on the Cell Proliferation ◦Generation of new daughter cells divided from progenitor (parent cells) Differentiation ◦Orderly process of cellular maturation to achieve a specific function Stem cells ◦Highly undifferentiated units Altered Cellular Proliferation and Differentiation Cellular proliferation and differentiation is under the control of genes. Neoplastic cells ignore genetic controls resulting in: ◦Excessive cellular proliferation (autonomy) ◦Loss of cellular differentiation (anaplasia) Carcinogenesis Origin and development of cancerous neoplasms Types of gene mutation affecting cell growth and division ◦Inherited (5% of cancers) ◦Acquired (95% of cancers)  Carcinogens Radiation Hormones Chemicals Tobacco Microbes  Initiation–Promotion– Progression Theory Initiation ◦Exposure of cells to a carcinogenic agent Promotion ◦A promoter agent activates oncogenes Progression ◦Independent growth Impact of Cancer on Tissues, Organs, and Organ Systems Autonomy ◦Unregulated proliferation of neoplasm Anaplasia ◦Loss of cell differentiation and function Impact of Cancer on Tissues, Organs, and Organ Systems Benign tumors ◦Remain localized ◦Closely resemble tissue of origin Malignant tumors ◦Are invasive and destructive ◦Proliferate rapidly ◦Spread to other sites (metastasize) ◦Do not resemble tissue of origin Cancer Spread Local spread Metastasis  General Manifestations of Cancer Lymphadenopathy Fever Anorexia Cachexia Palpable mass Loss of tissue function–variable depending on site Application of the Concepts of Altered Cell Proliferation and Differentiation Lung cancer Colon cancer Brain cancer Leukemia Lymphoma Lung Cancer Pathophysiology Clinical manifestations Lung Cancer Pathophysiology Leading cause of cancer deaths worldwide Smoking and industrial exposures often implicated Tumors originate most frequently in the epithelial lining of the bronchi, bronchioles, and alveoli Lung Cancer Clinical Manifestations Persistent cough Hemoptysis Chest pain Shortness of breath Question #5 Which of the following best describes the characteristics of a benign tumor? A. Remain Localized B. Invasive C. Destructive D. Rapidly Proliferation E. Spreads to Other Sites Answer to Question #5 Which of the following best describes the characteristics of a benign tumor? A. Remain Localized B. Invasive C. Destructive D. Rapidly Proliferation E. Spreads to Other Sites Stress and Adaptation  Stages of the General Adaptation Syndrome (Selye) Selye◊: Stress “is a state manifested by a specific syndrome of the body developed in response to any stimuli that made an intense systemic demand on it.” General Adaptation Syndrome (GAS) Alarm Stage – A generalized stimulation of the sympathetic nervous system and the HPA* axis resulting in release of catecholamines and cortisol. (Fight or flight!) Resistance Stage – The body selects the most effective and economic channels of defense. Exhaustion Stage – If resistance continues, resources are depleted and signs of “wear and tear” or systemic damage appears. ◊ Selye was an important guy who did a lot of important work a long time ago! *Hypothalamic-pituitary-adrenal Stressors Events or environmental agents responsible for initiating the stress response Can be endogenous or exogenous or a mix of both Types – Eustress – Mild, brief, and controllable periods of stress – Can be perceived as positive stimuli to emotional and intellectual growth and development. (This is almost like being a student in NUR 318.) – Distress – Severe, protracted, and uncontrolled situation and psychological and physical distress that are disruptive to health. (Do not even begin to think that NUR 318 falls into this category!)  Determining factors in stress response The properties of the stressor The same stressor may affect different people in different ways The conditioning of the person being stressed Internal: genetic predisposition, age, sex External: exposure to environmental agents, life experiences, dietary factors, level of social support Question #6 Henry R. is a performer. He spends night after night on stage doing speaking routines and playing in his band. Due to his schedule, he does not sleep enough and has a very poor diet. Which type of stress is Henry R. putting his body in? A. Eustress B. Distress C. Compress Answer to Question #6 Henry R. is a performer. He spends night after night on stage doing speaking routines and playing in his band. Due to his schedule, he does not sleep enough and has a very poor diet. Which type of stress is Henry R. putting his body in? A. Eustress B. Distress C. Compress Reactions to Acute Stress: FIGHT or FLIGHT Facilitation of neural pathways mediating arousal Alertness Vigilance Cognition Focused attention Appropriate aggression Reactions to Chronic Stress Pathophysiologic changes occur. Altered physiological function – Cardiovascular , gastrointestin al Altered psychological factors Depression , drug abuse, eating disorders  Can we Adapt to stress? Consider how each of these affect adaptation Previous learning and physiologic reserve Time Gradual or sudden onset of stress Genetic endowment Age Effects of young vs mid vs old Health status Nutrition Sleep–wake cycles (circadian rhythms) Hardiness Psychosocial factors Learning and Experience in Stress Reaction Adaptation implies that an individual has successfully created a new balance between the stressor and the ability to deal with stress. Coping mechanisms Emotional Behavioral Social Support and Adaptation to Stress Social support has direct and indirect positive effects on health status. Persons who have social supports or social assets may live longer and have a lower incidence of somatic illness. (This is VERY important in the Nursing School Experience!) Treatment Modalities for Stress Helping people avoid behaviors and situations Providing people with alternative stress- reducing strategies Purposeful priority setting and problem solving Like studying and THEN having fun!  Non-pharmacologic methods of stress  Non-pharmacologic Methods of Stress Reduction Relaxation techniques Guided imagery Music therapy Massage Therapy Biofeedback