Endocrine System 1. What are hormones and what is their function in the body? Hormones are chemical messengers transported in the bloodstream that stimulate physiological responses in target cells or organs. 2. Types of hormones Endocrine System 1. What are hormones and what is their function in the body? Hormones are chemical messengers transported in the bloodstream that stimulate physiological responses in target cells or organs. 2. Types of hormones based on chemical composition and how they enter target cells: • Steroid hormones: Lipid-soluble, diffuse through cell membrane (e.g., cortisol). • Protein/Peptide hormones: Water-soluble, bind to surface receptors (e.g., insulin). • Biogenic/Monoamines: Derived from amino acids (e.g., T3/T4), may need carriers or membrane receptors. 3. Know all 6 hormones secreted by the anterior pituitary gland and their functions: • TSH: Stimulates thyroid to release T3 and T4. • ACTH: Stimulates adrenal cortex to release cortisol. • GH: Stimulates tissue growth and protein synthesis. • PRL: Stimulates milk production. • FSH: Stimulates egg maturation/sperm production. • LH: Triggers ovulation and testosterone production. 4. What is thymosin? Which gland secretes it? What is its function? Thymosin is secreted by the thymus and helps in the development and maturation of T-cells. 5. Know thyroid gland hormones, the cells that secrete them, and their functions: • T3 & T4 (follicular cells): Increase metabolism and regulate appetite. • Calcitonin (C cells): Lowers blood calcium levels. 6. Know the hormones secreted by the adrenal gland and their specific functions: • Cortex: • Aldosterone: Retains Na⁺, excretes K⁺, raises blood pressure. • Cortisol: Increases glucose, metabolism of fat/protein. • Androgens: Precursor to sex hormones. • Medulla: • Epinephrine/Norepinephrine: Increase heart rate, blood flow, and alertness. 7. Function of glucagon and insulin in maintaining homeostasis: • Insulin (beta cells): Lowers blood glucose. • Glucagon (alpha cells): Raises blood glucose. • Antagonistic: They have opposing effects to balance blood sugar levels. 8. Which cells are involved in spermatogenesis? Where does sperm production occur? • Sertoli (Sustentacular) cells support spermatogenesis. • Leydig (Interstitial) cells produce testosterone. • Occurs in the seminiferous tubules of the testes. 9. Know the hormones secreted by the testes and their functions: • Testosterone: Stimulates male development and sperm production. • Inhibin: Inhibits FSH to regulate sperm production. 10. What causes diabetes insipidus? How is it different from diabetes mellitus? • Diabetes insipidus: ADH deficiency → excessive urination. • Diabetes mellitus: Insulin issues → high blood glucose. 11. Know the 3 “P’s” of diabetes: • Polyuria: Excessive urination. • Polydipsia: Excessive thirst. • Polyphagia: Excessive hunger. 12. How are oxytocin and prolactin different? • Oxytocin: Stimulates uterine contractions and milk letdown. • Prolactin: Stimulates milk production. 13. Name the ovarian hormones and their functions: • Estrogen/Progesterone: Regulate cycle, pregnancy, and secondary sex characteristics. • Inhibin: Inhibits FSH secretion. ⸻ Muscle Physiology 14. Know 3 muscle types, their locations, and function: • Skeletal: Attached to bones; movement; voluntary. • Cardiac: Heart; pumps blood; involuntary. • Smooth: Organs/vessels; propels substances; involuntary. 15. Know the layers surrounding muscle: • Epimysium: Surrounds entire muscle. • Perimysium: Surrounds fascicle (bundle). • Endomysium: Surrounds individual fiber. 16. What is a fascicle? A bundle of muscle fibers. 17. What is a sarcomere? Name its regions: Smallest contractile unit (Z-disc to Z-disc). • Z-band, A-band (dark), I-band (light), H-zone. 18. What are actin and myosin? • Actin: Thin filament. • Myosin: Thick filament that pulls actin during contraction. 19. What is troponin and tropomyosin? • Tropomyosin blocks binding sites on actin. • Troponin binds Ca²⁺ to move tropomyosin and expose sites. 20. What is a motor unit? A motor neuron and all muscle fibers it controls. 21. Role of T-Tubule, SR, Terminal Cisternae: • T-Tubule: Conducts AP into cell. • SR: Stores calcium. • Terminal cisternae: Release calcium. 22. Which neurotransmitter is released at the neuromuscular junction? Acetylcholine (ACh). 23. What role does Ca²⁺ play in muscle physiology? Binds troponin, moves tropomyosin, exposes actin sites. 24. What happens to Ca²⁺ after action potential ends? Reabsorbed into SR by Ca²⁺ ATPase pump. 25. What is the function of ATP in muscle physiology? Powers myosin movement, detachment, and Ca²⁺ reuptake. 26. What is sliding filament theory? Myosin pulls actin filaments → sarcomere shortens → contraction. 27. What are DHP and Ryanodine receptors and their roles? • DHP: Voltage sensor in T-tubule. • Ryanodine: Releases Ca²⁺ from SR. 28. What is the function of AChE? Breaks down ACh to stop stimulation and contraction. 29. Difference between isotonic and isometric contractions: • Isotonic: Muscle changes length (shortens/lengthens). • Isometric: Muscle length stays same; tension builds. ⸻ Respiratory Physiology 30. Difference between conductive and respiratory divisions: • Conductive: Air passageways (nose to bronchioles). • Respiratory: Gas exchange (alveoli). 31. Type I & II alveolar cells and functions: • Type I: Gas exchange. • Type II: Secretes surfactant, repairs alveoli. 32. Dust cells and their functions: Alveolar macrophages that clean up particles/debris. 33. Muscles in relaxed vs. forced respiration: • Relaxed inhale: Diaphragm, external intercostals. • Forced inhale: Accessory neck muscles. • Forced exhale: Internal intercostals, abdominals. 34. What happens to pressure and volume when inhaling/exhaling? • Inhale: Volume ↑, pressure ↓. • Exhale: Volume ↓, pressure ↑. 35. Difference between systemic and pulmonary exchange: • Systemic: Gas exchange at tissues. • Pulmonary: Gas exchange in lungs. 36. What cells are involved in carrying gases? Red blood cells (RBCs). 37. Which enzyme converts CO₂ + H₂O → H₂CO₃? Carbonic anhydrase. 38. What does carbonic acid break into? H⁺ + HCO₃⁻ (bicarbonate ion). 39. What happens in hypoxia (low oxygen)? • ↓O₂, ↑CO₂, ↓pH (acidosis). 40. What happens in hypercapnia (high CO₂)? • ↑CO₂, ↓O₂, ↓pH (acidosis). 41. Receptors for blood pH and their locations: • Central (CSF pH): Medulla oblongata. • Peripheral (O₂, CO₂, pH): Carotid & aortic bodies. 42. CO₂ loading & O₂ unloading at tissues: • CO₂ enters blood → forms HCO₃⁻. • O₂ released to tissues. 43. CO₂ unloading & O₂ loading at alveoli: • CO₂ released from blood to lungs. • O₂ binds to hemoglobin. 44. Brain part for unconscious breathing: Medulla oblongata. 45. Obstructive vs. restrictive disorders + example: • Obstructive: Narrowed airways (asthma). • Restrictive: Reduced lung expansion (fibrosis). 46. Know spirometry volumes (not numbers): • Tidal volume, • Inspiratory/Expiratory reserve volume, • Residual volume, • Vital capacity, • Total lung capacity, • Inspiratory capacity, • Functional residual capacity. 47. Define eupnea, dyspnea, tachypnea, apnea, Kussmaul respiration: • Eupnea: Normal breathing. • Dyspnea: Labored breathing. • Tachypnea: Rapid, shallow breathing. • Apnea: No breathing. • Kussmaul: Deep, rapid (from acidosis Endocrine System 1. What are hormones and what is their function in the body? Hormones are chemical messengers transported in the bloodstream that stimulate physiological responses in target cells or organs. 2. Types of hormones based on chemical composition and how they enter target cells: • Steroid hormones: Lipid-soluble, diffuse through cell membrane (e.g., cortisol). • Protein/Peptide hormones: Water-soluble, bind to surface receptors (e.g., insulin). • Biogenic/Monoamines: Derived from amino acids (e.g., T3/T4), may need carriers or membrane receptors. 3. Know all 6 hormones secreted by the anterior pituitary gland and their functions: • TSH: Stimulates thyroid to release T3 and T4. • ACTH: Stimulates adrenal cortex to release cortisol. • GH: Stimulates tissue growth and protein synthesis. • PRL: Stimulates milk production. • FSH: Stimulates egg maturation/sperm production. • LH: Triggers ovulation and testosterone production. 4. What is thymosin? Which gland secretes it? What is its function? Thymosin is secreted by the thymus and helps in the development and maturation of T-cells. 5. Know thyroid gland hormones, the cells that secrete them, and their functions: • T3 & T4 (follicular cells): Increase metabolism and regulate appetite. • Calcitonin (C cells): Lowers blood calcium levels. 6. Know the hormones secreted by the adrenal gland and their specific functions: • Cortex: • Aldosterone: Retains Na⁺, excretes K⁺, raises blood pressure. • Cortisol: Increases glucose, metabolism of fat/protein. • Androgens: Precursor to sex hormones. • Medulla: • Epinephrine/Norepinephrine: Increase heart rate, blood flow, and alertness. 7. Function of glucagon and insulin in maintaining homeostasis: • Insulin (beta cells): Lowers blood glucose. • Glucagon (alpha cells): Raises blood glucose. • Antagonistic: They have opposing effects to balance blood sugar levels. 8. Which cells are involved in spermatogenesis? Where does sperm production occur? • Sertoli (Sustentacular) cells support spermatogenesis. • Leydig (Interstitial) cells produce testosterone. • Occurs in the seminiferous tubules of the testes. 9. Know the hormones secreted by the testes and their functions: • Testosterone: Stimulates male development and sperm production. • Inhibin: Inhibits FSH to regulate sperm production. 10. What causes diabetes insipidus? How is it different from diabetes mellitus? • Diabetes insipidus: ADH deficiency → excessive urination. • Diabetes mellitus: Insulin issues → high blood glucose. 11. Know the 3 “P’s” of diabetes: • Polyuria: Excessive urination. • Polydipsia: Excessive thirst. • Polyphagia: Excessive hunger. 12. How are oxytocin and prolactin different? • Oxytocin: Stimulates uterine contractions and milk letdown. • Prolactin: Stimulates milk production. 13. Name the ovarian hormones and their functions: • Estrogen/Progesterone: Regulate cycle, pregnancy, and secondary sex characteristics. • Inhibin: Inhibits FSH secretion. ⸻ Muscle Physiology 14. Know 3 muscle types, their locations, and function: • Skeletal: Attached to bones; movement; voluntary. • Cardiac: Heart; pumps blood; involuntary. • Smooth: Organs/vessels; propels substances; involuntary. 15. Know the layers surrounding muscle: • Epimysium: Surrounds entire muscle. • Perimysium: Surrounds fascicle (bundle). • Endomysium: Surrounds individual fiber. 16. What is a fascicle? A bundle of muscle fibers. 17. What is a sarcomere? Name its regions: Smallest contractile unit (Z-disc to Z-disc). • Z-band, A-band (dark), I-band (light), H-zone. 18. What are actin and myosin? • Actin: Thin filament. • Myosin: Thick filament that pulls actin during contraction. 19. What is troponin and tropomyosin? • Tropomyosin blocks binding sites on actin. • Troponin binds Ca²⁺ to move tropomyosin and expose sites. 20. What is a motor unit? A motor neuron and all muscle fibers it controls. 21. Role of T-Tubule, SR, Terminal Cisternae: • T-Tubule: Conducts AP into cell. • SR: Stores calcium. • Terminal cisternae: Release calcium. 22. Which neurotransmitter is released at the neuromuscular junction? Acetylcholine (ACh). 23. What role does Ca²⁺ play in muscle physiology? Binds troponin, moves tropomyosin, exposes actin sites. 24. What happens to Ca²⁺ after action potential ends? Reabsorbed into SR by Ca²⁺ ATPase pump. 25. What is the function of ATP in muscle physiology? Powers myosin movement, detachment, and Ca²⁺ reuptake. 26. What is sliding filament theory? Myosin pulls actin filaments → sarcomere shortens → contraction. 27. What are DHP and Ryanodine receptors and their roles? • DHP: Voltage sensor in T-tubule. • Ryanodine: Releases Ca²⁺ from SR. 28. What is the function of AChE? Breaks down ACh to stop stimulation and contraction. 29. Difference between isotonic and isometric contractions: • Isotonic: Muscle changes length (shortens/lengthens). • Isometric: Muscle length stays same; tension builds. ⸻ Respiratory Physiology 30. Difference between conductive and respiratory divisions: • Conductive: Air passageways (nose to bronchioles). • Respiratory: Gas exchange (alveoli). 31. Type I & II alveolar cells and functions: • Type I: Gas exchange. • Type II: Secretes surfactant, repairs alveoli. 32. Dust cells and their functions: Alveolar macrophages that clean up particles/debris. 33. Muscles in relaxed vs. forced respiration: • Relaxed inhale: Diaphragm, external intercostals. • Forced inhale: Accessory neck muscles. • Forced exhale: Internal intercostals, abdominals. 34. What happens to pressure and volume when inhaling/exhaling? • Inhale: Volume ↑, pressure ↓. • Exhale: Volume ↓, pressure ↑. 35. Difference between systemic and pulmonary exchange: • Systemic: Gas exchange at tissues. • Pulmonary: Gas exchange in lungs. 36. What cells are involved in carrying gases? Red blood cells (RBCs). 37. Which enzyme converts CO₂ + H₂O → H₂CO₃? Carbonic anhydrase. 38. What does carbonic acid break into? H⁺ + HCO₃⁻ (bicarbonate ion). 39. What happens in hypoxia (low oxygen)? • ↓O₂, ↑CO₂, ↓pH (acidosis). 40. What happens in hypercapnia (high CO₂)? • ↑CO₂, ↓O₂, ↓pH (acidosis). 41. Receptors for blood pH and their locations: • Central (CSF pH): Medulla oblongata. • Peripheral (O₂, CO₂, pH): Carotid & aortic bodies. 42. CO₂ loading & O₂ unloading at tissues: • CO₂ enters blood → forms HCO₃⁻. • O₂ released to tissues. 43. CO₂ unloading & O₂ loading at alveoli: • CO₂ released from blood to lungs. • O₂ binds to hemoglobin. 44. Brain part for unconscious breathing: Medulla oblongata. 45. Obstructive vs. restrictive disorders + example: • Obstructive: Narrowed airways (asthma). • Restrictive: Reduced lung expansion (fibrosis). 46. Know spirometry volumes (not numbers): • Tidal volume, • Inspiratory/Expiratory reserve volume, • Residual volume, • Vital capacity, • Total lung capacity, • Inspiratory capacity, • Functional residual capacity. 47. Define eupnea, dyspnea, tachypnea, apnea, Kussmaul respiration: • Eupnea: Normal breathing. • Dyspnea: Labored breathing. • Tachypnea: Rapid, shallow breathing. • Apnea: No breathing. • Kussmaul: Deep, rapid (from acidosis Endocrine System 1. What are hormones and what is their function in the body? Hormones are chemical messengers transported in the bloodstream that stimulate physiological responses in target cells or organs. 2. Types of hormones based on chemical composition and how they enter target cells: • Steroid hormones: Lipid-soluble, diffuse through cell membrane (e.g., cortisol). • Protein/Peptide hormones: Water-soluble, bind to surface receptors (e.g., insulin). • Biogenic/Monoamines: Derived from amino acids (e.g., T3/T4), may need carriers or membrane receptors. 3. Know all 6 hormones secreted by the anterior pituitary gland and their functions: • TSH: Stimulates thyroid to release T3 and T4. • ACTH: Stimulates adrenal cortex to release cortisol. • GH: Stimulates tissue growth and protein synthesis. • PRL: Stimulates milk production. • FSH: Stimulates egg maturation/sperm production. • LH: Triggers ovulation and testosterone production. 4. What is thymosin? Which gland secretes it? What is its function? Thymosin is secreted by the thymus and helps in the development and maturation of T-cells. 5. Know thyroid gland hormones, the cells that secrete them, and their functions: • T3 & T4 (follicular cells): Increase metabolism and regulate appetite. • Calcitonin (C cells): Lowers blood calcium levels. 6. Know the hormones secreted by the adrenal gland and their specific functions: • Cortex: • Aldosterone: Retains Na⁺, excretes K⁺, raises blood pressure. • Cortisol: Increases glucose, metabolism of fat/protein. • Androgens: Precursor to sex hormones. • Medulla: • Epinephrine/Norepinephrine: Increase heart rate, blood flow, and alertness. 7. Function of glucagon and insulin in maintaining homeostasis: • Insulin (beta cells): Lowers blood glucose. • Glucagon (alpha cells): Raises blood glucose. • Antagonistic: They have opposing effects to balance blood sugar levels. 8. Which cells are involved in spermatogenesis? Where does sperm production occur? • Sertoli (Sustentacular) cells support spermatogenesis. • Leydig (Interstitial) cells produce testosterone. • Occurs in the seminiferous tubules of the testes. 9. Know the hormones secreted by the testes and their functions: • Testosterone: Stimulates male development and sperm production. • Inhibin: Inhibits FSH to regulate sperm production. 10. What causes diabetes insipidus? How is it different from diabetes mellitus? • Diabetes insipidus: ADH deficiency → excessive urination. • Diabetes mellitus: Insulin issues → high blood glucose. 11. Know the 3 “P’s” of diabetes: • Polyuria: Excessive urination. • Polydipsia: Excessive thirst. • Polyphagia: Excessive hunger. 12. How are oxytocin and prolactin different? • Oxytocin: Stimulates uterine contractions and milk letdown. • Prolactin: Stimulates milk production. 13. Name the ovarian hormones and their functions: • Estrogen/Progesterone: Regulate cycle, pregnancy, and secondary sex characteristics. • Inhibin: Inhibits FSH secretion. ⸻ Muscle Physiology 14. Know 3 muscle types, their locations, and function: • Skeletal: Attached to bones; movement; voluntary. • Cardiac: Heart; pumps blood; involuntary. • Smooth: Organs/vessels; propels substances; involuntary. 15. Know the layers surrounding muscle: • Epimysium: Surrounds entire muscle. • Perimysium: Surrounds fascicle (bundle). • Endomysium: Surrounds individual fiber. 16. What is a fascicle? A bundle of muscle fibers. 17. What is a sarcomere? Name its regions: Smallest contractile unit (Z-disc to Z-disc). • Z-band, A-band (dark), I-band (light), H-zone. 18. What are actin and myosin? • Actin: Thin filament. • Myosin: Thick filament that pulls actin during contraction. 19. What is troponin and tropomyosin? • Tropomyosin blocks binding sites on actin. • Troponin binds Ca²⁺ to move tropomyosin and expose sites. 20. What is a motor unit? A motor neuron and all muscle fibers it controls. 21. Role of T-Tubule, SR, Terminal Cisternae: • T-Tubule: Conducts AP into cell. • SR: Stores calcium. • Terminal cisternae: Release calcium. 22. Which neurotransmitter is released at the neuromuscular junction? Acetylcholine (ACh). 23. What role does Ca²⁺ play in muscle physiology? Binds troponin, moves tropomyosin, exposes actin sites. 24. What happens to Ca²⁺ after action potential ends? Reabsorbed into SR by Ca²⁺ ATPase pump. 25. What is the function of ATP in muscle physiology? Powers myosin movement, detachment, and Ca²⁺ reuptake. 26. What is sliding filament theory? Myosin pulls actin filaments → sarcomere shortens → contraction. 27. What are DHP and Ryanodine receptors and their roles? • DHP: Voltage sensor in T-tubule. • Ryanodine: Releases Ca²⁺ from SR. 28. What is the function of AChE? Breaks down ACh to stop stimulation and contraction. 29. Difference between isotonic and isometric contractions: • Isotonic: Muscle changes length (shortens/lengthens). • Isometric: Muscle length stays same; tension builds. ⸻ Respiratory Physiology 30. Difference between conductive and respiratory divisions: • Conductive: Air passageways (nose to bronchioles). • Respiratory: Gas exchange (alveoli). 31. Type I & II alveolar cells and functions: • Type I: Gas exchange. • Type II: Secretes surfactant, repairs alveoli. 32. Dust cells and their functions: Alveolar macrophages that clean up particles/debris. 33. Muscles in relaxed vs. forced respiration: • Relaxed inhale: Diaphragm, external intercostals. • Forced inhale: Accessory neck muscles. • Forced exhale: Internal intercostals, abdominals. 34. What happens to pressure and volume when inhaling/exhaling? • Inhale: Volume ↑, pressure ↓. • Exhale: Volume ↓, pressure ↑. 35. Difference between systemic and pulmonary exchange: • Systemic: Gas exchange at tissues. • Pulmonary: Gas exchange in lungs. 36. What cells are involved in carrying gases? Red blood cells (RBCs). 37. Which enzyme converts CO₂ + H₂O → H₂CO₃? Carbonic anhydrase. 38. What does carbonic acid break into? H⁺ + HCO₃⁻ (bicarbonate ion). 39. What happens in hypoxia (low oxygen)? • ↓O₂, ↑CO₂, ↓pH (acidosis). 40. What happens in hypercapnia (high CO₂)? • ↑CO₂, ↓O₂, ↓pH (acidosis). 41. Receptors for blood pH and their locations: • Central (CSF pH): Medulla oblongata. • Peripheral (O₂, CO₂, pH): Carotid & aortic bodies. 42. CO₂ loading & O₂ unloading at tissues: • CO₂ enters blood → forms HCO₃⁻. • O₂ released to tissues. 43. CO₂ unloading & O₂ loading at alveoli: • CO₂ released from blood to lungs. • O₂ binds to hemoglobin. 44. Brain part for unconscious breathing: Medulla oblongata. 45. Obstructive vs. restrictive disorders + example: • Obstructive: Narrowed airways (asthma). • Restrictive: Reduced lung expansion (fibrosis). 46. Know spirometry volumes (not numbers): • Tidal volume, • Inspiratory/Expiratory reserve volume, • Residual volume, • Vital capacity, • Total lung capacity, • Inspiratory capacity, • Functional residual capacity. 47. Define eupnea, dyspnea, tachypnea, apnea, Kussmaul respiration: • Eupnea: Normal breathing. • Dyspnea: Labored breathing. • Tachypnea: Rapid, shallow breathing. • Apnea: No breathing. • Kussmaul: Deep, rapid (from acidosis based on chemical composition and how they enter target cells: • Steroid hormones: Lipid-soluble, diffuse through cell membrane (e.g., cortisol). • Protein/Peptide hormones: Water-soluble, bind to surface receptors (e.g., insulin). • Biogenic/Monoamines: Derived from amino acids (e.g., T3/T4), may need carriers or membrane receptors. 3. Know all 6 hormones secreted by the anterior pituitary gland and their functions: • TSH: Stimulates thyroid to release T3 and T4. • ACTH: Stimulates adrenal cortex to release cortisol. • GH: Stimulates tissue growth and protein synthesis. • PRL: Stimulates milk production. • FSH: Stimulates egg maturation/sperm production. • LH: Triggers ovulation and testosterone production. 4. What is thymosin? Which gland secretes it? What is its function? Thymosin is secreted by the thymus and helps in the development and maturation of T-cells. 5. Know thyroid gland hormones, the cells that secrete them, and their functions: • T3 & T4 (follicular cells): Increase metabolism and regulate appetite. • Calcitonin (C cells): Lowers blood calcium levels. 6. Know the hormones secreted by the adrenal gland and their specific functions: • Cortex: • Aldosterone: Retains Na⁺, excretes K⁺, raises blood pressure. • Cortisol: Increases glucose, metabolism of fat/protein. • Androgens: Precursor to sex hormones. • Medulla: • Epinephrine/Norepinephrine: Increase heart rate, blood flow, and alertness. 7. Function of glucagon and insulin in maintaining homeostasis: • Insulin (beta cells): Lowers blood glucose. • Glucagon (alpha cells): Raises blood glucose. • Antagonistic: They have opposing effects to balance blood sugar levels. 8. Which cells are involved in spermatogenesis? Where does sperm production occur? • Sertoli (Sustentacular) cells support spermatogenesis. • Leydig (Interstitial) cells produce testosterone. • Occurs in the seminiferous tubules of the testes. 9. Know the hormones secreted by the testes and their functions: • Testosterone: Stimulates male development and sperm production. • Inhibin: Inhibits FSH to regulate sperm production. 10. What causes diabetes insipidus? How is it different from diabetes mellitus? • Diabetes insipidus: ADH deficiency → excessive urination. • Diabetes mellitus: Insulin issues → high blood glucose. 11. Know the 3 “P’s” of diabetes: • Polyuria: Excessive urination. • Polydipsia: Excessive thirst. • Polyphagia: Excessive hunger. 12. How are oxytocin and prolactin different? • Oxytocin: Stimulates uterine contractions and milk letdown. • Prolactin: Stimulates milk production. 13. Name the ovarian hormones and their functions: • Estrogen/Progesterone: Regulate cycle, pregnancy, and secondary sex characteristics. • Inhibin: Inhibits FSH secretion. ⸻ Muscle Physiology 14. Know 3 muscle types, their locations, and function: • Skeletal: Attached to bones; movement; voluntary. • Cardiac: Heart; pumps blood; involuntary. • Smooth: Organs/vessels; propels substances; involuntary. 15. Know the layers surrounding muscle: • Epimysium: Surrounds entire muscle. • Perimysium: Surrounds fascicle (bundle). • Endomysium: Surrounds individual fiber. 16. What is a fascicle? A bundle of muscle fibers. 17. What is a sarcomere? Name its regions: Smallest contractile unit (Z-disc to Z-disc). • Z-band, A-band (dark), I-band (light), H-zone. 18. What are actin and myosin? • Actin: Thin filament. • Myosin: Thick filament that pulls actin during contraction. 19. What is troponin and tropomyosin? • Tropomyosin blocks binding sites on actin. • Troponin binds Ca²⁺ to move tropomyosin and expose sites. 20. What is a motor unit? A motor neuron and all muscle fibers it controls. 21. Role of T-Tubule, SR, Terminal Cisternae: • T-Tubule: Conducts AP into cell. • SR: Stores calcium. • Terminal cisternae: Release calcium. 22. Which neurotransmitter is released at the neuromuscular junction? Acetylcholine (ACh). 23. What role does Ca²⁺ play in muscle physiology? Binds troponin, moves tropomyosin, exposes actin sites. 24. What happens to Ca²⁺ after action potential ends? Reabsorbed into SR by Ca²⁺ ATPase pump. 25. What is the function of ATP in muscle physiology? Powers myosin movement, detachment, and Ca²⁺ reuptake. 26. What is sliding filament theory? Myosin pulls actin filaments → sarcomere shortens → contraction. 27. What are DHP and Ryanodine receptors and their roles? • DHP: Voltage sensor in T-tubule. • Ryanodine: Releases Ca²⁺ from SR. 28. What is the function of AChE? Breaks down ACh to stop stimulation and contraction. 29. Difference between isotonic and isometric contractions: • Isotonic: Muscle changes length (shortens/lengthens). • Isometric: Muscle length stays same; tension builds. ⸻ Respiratory Physiology 30. Difference between conductive and respiratory divisions: • Conductive: Air passageways (nose to bronchioles). • Respiratory: Gas exchange (alveoli). 31. Type I & II alveolar cells and functions: • Type I: Gas exchange. • Type II: Secretes surfactant, repairs alveoli. 32. Dust cells and their functions: Alveolar macrophages that clean up particles/debris. 33. Muscles in relaxed vs. forced respiration: • Relaxed inhale: Diaphragm, external intercostals. • Forced inhale: Accessory neck muscles. • Forced exhale: Internal intercostals, abdominals. 34. What happens to pressure and volume when inhaling/exhaling? • Inhale: Volume ↑, pressure ↓. • Exhale: Volume ↓, pressure ↑. 35. Difference between systemic and pulmonary exchange: • Systemic: Gas exchange at tissues. • Pulmonary: Gas exchange in lungs. 36. What cells are involved in carrying gases? Red blood cells (RBCs). 37. Which enzyme converts CO₂ + H₂O → H₂CO₃? Carbonic anhydrase. 38. What does carbonic acid break into? H⁺ + HCO₃⁻ (bicarbonate ion). 39. What happens in hypoxia (low oxygen)? • ↓O₂, ↑CO₂, ↓pH (acidosis). 40. What happens in hypercapnia (high CO₂)? • ↑CO₂, ↓O₂, ↓pH (acidosis). 41. Receptors for blood pH and their locations: • Central (CSF pH): Medulla oblongata. • Peripheral (O₂, CO₂, pH): Carotid & aortic bodies. 42. CO₂ loading & O₂ unloading at tissues: • CO₂ enters blood → forms HCO₃⁻. • O₂ released to tissues. 43. CO₂ unloading & O₂ loading at alveoli: • CO₂ released from blood to lungs. • O₂ binds to hemoglobin. 44. Brain part for unconscious breathing: Medulla oblongata. 45. Obstructive vs. restrictive disorders + example: • Obstructive: Narrowed airways (asthma). • Restrictive: Reduced lung expansion (fibrosis). 46. Know spirometry volumes (not numbers): • Tidal volume, • Inspiratory/Expiratory reserve volume, • Residual volume, • Vital capacity, • Total lung capacity, • Inspiratory capacity, • Functional residual capacity. 47. Define eupnea, dyspnea, tachypnea, apnea, Kussmaul respiration: • Eupnea: Normal breathing. • Dyspnea: Labored breathing. • Tachypnea: Rapid, shallow breathing. • Apnea: No breathing

Silk Road

A vast network of trade routes established during the Han Dynasty that connected the East to the West.

Han Dynasty

The dynasty in China during which the Silk Road was established.

Silk

The most valuable commodity traded along the Silk Road.

Commodities

Goods that can be traded, such as silk, spices, tea, porcelain, and precious metals.

Trade Routes

Paths followed by traders to facilitate the exchange of goods.

Spices

One of the goods exchanged on the Silk Road, highly valued for flavoring and preserving food.

Tea

A beverage that was one of the commodities traded along the Silk Road.

Porcelain

A ceramic material that was valued and traded via the Silk Road.

Precious Metals

Valued metals like gold and silver that were part of the trade on the Silk Road.

East to West

The direction of trade connection established by the Silk Road.

Traders

Individuals who participate in the exchange of goods along the Silk Road.