Histology of Cardiac Muscle & Heart Wall Quiz PDF

Okay, here is a 30-MCQ quiz based on the second lecture: Histology of Cardiac Muscle & Heart Wall Quiz (30 MCQs) Part One: Simple MCQs (10) 1. What is the approximate length of a cardiac muscle cell? a) 10 μm b) 100 μm c) 1000 μm d) 10000 μm 2. Where are T-tubules located in cardiac muscle cells?...

Okay, here is a 30-MCQ quiz based on the second lecture: Histology of Cardiac Muscle & Heart Wall Quiz (30 MCQs) Part One: Simple MCQs (10) 1. What is the approximate length of a cardiac muscle cell? a) 10 μm b) 100 μm c) 1000 μm d) 10000 μm 2. Where are T-tubules located in cardiac muscle cells? a) A-I junction b) Z-line c) M-line d) H-zone 3. What is the primary fuel source for cardiac muscle cells? a) Glucose b) Amino acids c) Fatty acids d) Ketone bodies 4. What type of junction is found in the longitudinal part of an intercalated disc? a) Desmosome b) Gap junction c) Tight junction d) Adherens junction 5. Which layer of the heart wall contains Purkinje fibers? a) Epicardium b) Myocardium c) Endocardium d) Pericardium 6. What is the main function of atrial natriuretic factor (ANF)? a) Increase blood pressure b) Decrease blood pressure c) Increase heart rate d) Decrease heart rate 7. Which layer of the heart wall is the thickest? a) Epicardium b) Myocardium c) Endocardium d) Pericardium 8. What type of epithelium lines the endocardium? a) Simple squamous b) Simple cuboidal c) Simple columnar d) Stratified squamous 9. Which part of the intercalated disc is responsible for the strong adhesion of cardiac muscle cells? a) Transverse part b) Longitudinal part c) Both a and b d) Neither a nor b 10. Which structure is more abundant in cardiac muscle compared to skeletal muscle? a) T-tubules b) Sarcoplasmic reticulum c) Myofibrils d) Nuclei Part Two: Complex MCQs (20) 11. Why are striations less distinct in cardiac muscle compared to skeletal muscle? a) Absence of myofibrils b) Irregular branching of cells c) Lack of actin and myosin filaments d) Central location of the nucleus 12. What is the functional significance of the abundance of mitochondria in cardiac muscle cells? a) Protein synthesis b) Lipid storage c) High energy demand d) Glycogenolysis 13. A histological slide shows a cardiac muscle fiber with a diad located at the Z-line. What does this diad consist of? a) One T-tubule and one sarcoplasmic reticulum cisterna b) Two T-tubules and one sarcoplasmic reticulum cisterna c) One T-tubule and two sarcoplasmic reticulum cisternae d) Two T-tubules and two sarcoplasmic reticulum cisternae 14. Which component of the intercalated disc allows for the rapid spread of electrical signals between cardiac muscle cells? a) Desmosomes b) Gap junctions c) Tight junctions d) Adherens junctions 15. Which layer of the heart wall is responsible for the heart's pumping action? a) Epicardium b) Myocardium c) Endocardium d) Pericardium 16. Which hormone has an antagonistic effect to ANF? a) Insulin b) Glucagon c) Aldosterone d) Epinephrine 17. Which feature distinguishes Purkinje fibers from ordinary cardiac muscle fibers? a) Smaller size b) Darker staining c) Abundant myofibrils d) High glycogen content 18. Which layer of the heart wall is continuous with the lining of blood vessels? a) Epicardium b) Myocardium c) Endocardium d) Pericardium 19. Which structure is found in the subendocardial layer and is responsible for transmitting electrical signals to the ventricular muscle? a) Purkinje fibers b) Atrioventricular node c) Sinoatrial node d) Internodal pathways 20. Which cell type is responsible for the endocrine function of the heart? a) Contractile cells of the ventricle b) Contractile cells of the atrium c) Purkinje fibers d) Endothelial cells 21. Which structure is a unique feature of cardiac muscle and plays a crucial role in synchronized contraction? a) T-tubules b) Sarcoplasmic reticulum c) Intercalated discs d) Myofibrils 22. Which structure is responsible for the structural integrity of the heart wall and prevents overdistension? a) Epicardium b) Myocardium c) Endocardium d) Pericardium 23. Which component of the intercalated disc contributes to the mechanical coupling of cardiac muscle cells? a) Desmosomes b) Gap junctions c) Tight junctions d) Adherens junctions 24. Which layer of the heart wall is composed of simple squamous mesothelium and loose connective tissue? a) Epicardium b) Myocardium c) Endocardium d) Pericardium 25. Which structure is responsible for the electrical insulation between atria and ventricles? a) Purkinje fibers b) Atrioventricular node c) Sinoatrial node d) Internodal pathways 26. Which feature allows for the efficient diffusion of nutrients and oxygen in cardiac muscle tissue? a) Rich capillary network in the endomysium b) Abundant lipid droplets in the sarcoplasm c) Presence of lipofuscin pigments d) Peripheral location of myofibrils in Purkinje fibers 27. Which structure is responsible for the initiation of the heartbeat? a) Purkinje fibers b) Atrioventricular node c) Sinoatrial node d) Internodal pathways 28. Which feature contributes to the rhythmic contraction of the heart? a) Presence of intercalated discs b) Abundance of mitochondria c) High glycogen content in Purkinje fibers d) Endocrine function of atrial muscle cells 29. Which structure is responsible for the rapid conduction of electrical impulses throughout the ventricles? a) Purkinje fibers b) Atrioventricular node c) Sinoatrial node d) Internodal pathways 30. Which feature allows for the coordinated contraction of cardiac muscle cells within a fiber? a) Branching of fibers b) Presence of intercalated discs c) Central location of the nucleus d) Abundance of mitochondria Answer Guide 1. b 2. b 3. c 4. b 5. c 6. b 7. b 8. a 9. a 10. a 11. b 12. c 13. a 14. b 15. b 16. c 17. d 18. c 19. a 20. b 21. c 22. b 23. a 24. a 25. b 26. a 27. c 28. a 29. a 30. b Done