Biology Answers Note #3

Question 1 what are fibrous septa in the liver - surrounding fine nodules Answer Fibrous septa are thin layers of connective tissue that surround fine nodules in the liver. The liver is a vital organ responsible for detoxification, metabolism, and storage of nutrients. It is also the largest internal organ in the human body and is constantly exposed to various toxins and diseases. The formation of fibrous septa in the liver is a common response to chronic liver diseases, such as cirrhosis, and can have significant implications for the overall function of the liver. One of the main functions of the liver is to filter blood from the digestive tract before it is circulated to the rest of the body. This process involves the liver cells, also known as hepatocytes, being arranged in lobules with a network of blood vessels and bile ducts. However, when the liver is exposed to chronic injury or inflammation, the hepatocytes can be damaged and replaced by scar tissue, which results in the formation of nodules. These nodules are surrounded by fibrous septa, which serve as a structural support for the liver. Fibrous septa are composed of collagen fibers and other proteins, which form a dense network around the nodules. This network of fibers can limit the blood flow to the affected areas, leading to reduced liver function. In addition, the nodules can also obstruct the flow of bile, which can further damage the liver and lead to the development of complications. Question 2 11.This structure temporarily shunts blood from the pulmonary trunk into the aorta in a fetus. A.Fossa ovalis B.Foramen ovale C.Trabeculae carnae D.Descending aorta E.Ductus arteriosus 12.As each ventricle contracts, where does blood move? A.Into an artery B.Into the apex C.Into a vein D.Through an atrioventricular valve E.Through the apex 13.As each atrium contracts, where does blood move? A.Into an auricle B.Into an artery C.Into a vein D.Through an atrioventricular valve E.Through a semilunar valve 14.Which of the below structures prevents blood from flowing back from the lungs? A.Tricuspid valve B.Bicuspid valve C.Pulmonary valve D.Aortic valve E.Pulmonary vein 15.In this disorder, the aortic valve is narrowed. A.Aortic insufficiency B.Rheumatic fever C.Mitral valve prolapse D.Aortic stenosis E.Aortic regurgitation 16.This vessel distributes oxygenated blood to the myocardium. A.Coronary artery B.Coronary vein C.Right ventricle D.Left auricle E.Myocardial vein 17.Cardiac muscle fibers electrically connect to neighboring fibers by A.Desmosomes B.Intermediate discs C.Gap junctions D.Contractile fibres E.Chordae tendinae 18.Which of the following contains the largest amount of mitochondria? A.Smooth muscle B.Skeletal muscle C.Cardiac muscle D.Hepatocytes E.Leukocytes 19.This is a network of specialized cardiac muscle fibers that provide a path for each cycle of cardiac excitation to progress through the heart. A.Pacemaker B.Sinoatrial node C.Purkinje fibres D.Conduction system E.Bundle of His 20.By comparison, cardiac muscle cells have _____________________ contraction plateau time than skeletal muscle cells. A.A shorter B.A longer C.No difference in 21.This is the volume of blood ejected from the left ventricle into the aorta each minute. A.Cardiac output B.Cardiac input C.Stroke volume D.Heart rate E.Auscultation 22.This term refers to the period during a cardiac cycle when contraction occurs and blood pressure rises. A.Filling B.Systole C.Repolarization D.Diastole E.Fibrillation 23.Which of the following heart chamber has thickest muscle layer? A.Right atrium B.Right ventricle C.Left ventricle D.Left atrium 24.Epicardium is closely attached with? A. Fibrous layer of pericardium B. Endocardium C. Parietal pericardium D. Visceral pericardium 25.Mitral valve is also known as? A.Aortic valve B.Bicuspid valve C.Pulmonic valve D.Tricuspid valve 26.What is the approximate weight of the heart of an adult person? A.550 g B.250 g C.325 g D.750 g 27.A groove or slight depression seen on external surface of the heart is known as? A.Atrio septal groove B.Cristae terminalis C.Sulcus terminalis D.Septum 28.How many papillary muscles are there in right side of the heart? A.1 B.3 C.2 D.5 29.Pericardial fluid is lubricating fluid seen in between? A.Parietal pericardium and fibrous pericardium B.endocardium and myocardium C.visceral pericardium and parietal pericardium D.myocardium and epicardium 30.Which boarder of the heart is known as diaphragmatic surface of the heart? A.Posterior boarder B.Left boarder C.Inferior boarder D.Right boarder Answer The correct answer is: B. Foramen ovale. This structure is a natural opening in the atrial septum of a fetus that allows blood to bypass the lungs and flow directly from the right atrium into the left atrium, and then to the aorta. This is necessary because the fetal lungs are not yet functioning and the blood needs to be oxygenated by the placenta. This shunting of blood is a temporary measure that is no longer necessary after birth, when the lungs begin to function and the foramen ovale closes. Throughout the cardiac cycle, the ventricles alternate between a state of relaxation (diastole) and contraction (systole). During systole, blood is ejected from the ventricles and moves out of the heart through the pulmonary artery from the right ventricle and the aorta from the left ventricle. Therefore, the correct answer is: A. Into an artery. During atrial contraction or systole, blood is forced into the ventricles through the atrioventricular (AV) valves. Therefore, the correct answer is: D. Through an atrioventricular valve. The correct answer is: C. Pulmonary valve. This valve is located at the entrance of the pulmonary artery and prevents the backflow of blood from the lungs into the right ventricle. This ensures that oxygenated blood from the lungs can flow out Question 3 Can you explain morphologically, how the stratified squamous epithelium is different from the respiratory epithelium Answer Morphologically, the stratified squamous epithelium is composed of multiple layers of flattened cells, while the respiratory epithelium is made up of a single layer of specialized cells called ciliated columnar cells. The stratified squamous epithelium is found in areas of the body that require protection, such as the skin and the lining of the mouth, while the respiratory epithelium is found in the respiratory tract. The main difference between these two epithelia is the presence of cilia in the respiratory epithelium, which helps in the movement of mucus and foreign particles out of the respiratory tract. Additionally, the respiratory epithelium also contains goblet cells, which secrete mucus to trap particles and keep the respiratory tract moist. Question 4 1.This is the layer that protects the heart. A.Epicardium B.Parietal layer C.Myocardial tissue D.Mediastinum E.Endocardium 2.Which of the following consists of inelastic dense irregular connective tissue? A.Parietal layer of pericardium B.Serous pericardium C.Fibrous pericardium D.Epicardium E.Pericardial cavity 3.This is used to reduce the friction between the membranes of the heart. A.Epicardium B.Endocardium layer C.Pericardium D.Pericardial (serous) fluid E.Pericardial cavity 4.This consists of mesothelium and connective tissue. A.Epicardium B.Myocardium C.Endocardium D.Pericardial cavity E.Fibrous pericardium 5.This is used to increase the capacity of the atrium. A.Ventricle B.Coronary sulcus C.Fossa ovalis D.Interatrial septum E.Auricle 6.Which layer consists of cardiac muscle tissue? A.Epicardium B.Pericardium C.Myocardium D.Endocardium E.Hypocardium 7.This marks the boundary between the ventricles. A.Coronary sulcus B.Anterior interventricular sulcus C.Posterior interventricular sulcus D.Coronary sulcus and posterior interventricular sulcus E.Anterior and posterior interventricular sulcus 8.These extend into the auricle. A.Pectinate muscles B.Interatrial septum C.Coronary sulcus D.Ventricle E.Chordae tendinae 9.Through which structure does blood pass from the right atrium to the right ventricle? A.Bicuspid valve B.Interventricular septum C.Tricuspid valve D.Mitral valve E.Ascending aorta 10.What types of tissue comprise the valves of the heart? A.Dense regular connective tissue B.Dense irregular connective tissue C.Areolar connective tissue D.Hyaline cartilage E.Cardiac muscle tissue 11.This structure temporarily shunts blood from the pulmonary trunk into the aorta in a fetus. A.Fossa ovalis B.Foramen ovale C.Trabeculae carnae D.Descending aorta E.Ductus arteriosus 12.As each ventricle contracts, where does blood move? A.Into an artery B.Into the apex C.Into a vein D.Through an atrioventricular valve E.Through the apex 13.As each atrium contracts, where does blood move? A.Into an auricle B.Into an artery C.Into a vein D.Through an atrioventricular valve E.Through a semilunar valve 14.Which of the below structures prevents blood from flowing back from the lungs? A.Tricuspid valve B.Bicuspid valve C.Pulmonary valve D.Aortic valve E.Pulmonary vein 15.In this disorder, the aortic valve is narrowed. A.Aortic insufficiency B.Rheumatic fever C.Mitral valve prolapse D.Aortic stenosis E.Aortic regurgitation 16.This vessel distributes oxygenated blood to the myocardium. A.Coronary artery B.Coronary vein C.Right ventricle D.Left auricle E.Myocardial vein 17.Cardiac muscle fibers electrically connect to neighboring fibers by A.Desmosomes B.Intermediate discs C.Gap junctions D.Contractile fibres E.Chordae tendinae 18.Which of the following contains the largest amount of mitochondria? A.Smooth muscle B.Skeletal muscle C.Cardiac muscle D.Hepatocytes E.Leukocytes 19.This is a network of specialized cardiac muscle fibers that provide a path for each cycle of cardiac excitation to progress through the heart. A.Pacemaker B.Sinoatrial node C.Purkinje fibres D.Conduction system E.Bundle of His 20.By comparison, cardiac muscle cells have _____________________ contraction plateau time than skeletal muscle cells. A.A shorter B.A longer C.No difference in 21.This is the volume of blood ejected from the left ventricle into the aorta each minute. A.Cardiac output B.Cardiac input C.Stroke volume D.Heart rate E.Auscultation 22.This term refers to the period during a cardiac cycle when contraction occurs and blood pressure rises. A.Filling B.Systole C.Repolarization D.Diastole E.Fibrillation 23.Which of the following heart chamber has thickest muscle layer? A.Right atrium B.Right ventricle C.Left ventricle D.Left atrium 24.Epicardium is closely attached with? A. Fibrous layer of pericardium B. Endocardium C. Parietal pericardium D. Visceral pericardium 25.Mitral valve is also known as? A.Aortic valve B.Bicuspid valve C.Pulmonic valve D.Tricuspid valve 26.What is the approximate weight of the heart of an adult person? A.550 g B.250 g C.325 g D.750 g 27.A groove or slight depression seen on external surface of the heart is known as? A.Atrio septal groove B.Cristae terminalis C.Sulcus terminalis D.Septum 28.How many papillary muscles are there in right side of the heart? A.1 B.3 C.2 D.5 29.Pericardial fluid is lubricating fluid seen in between? A.Parietal pericardium and fibrous pericardium B.endocardium and myocardium C.visceral pericardium and parietal pericardium D.myocardium and epicardium 30.Which boarder of the heart is known as diaphragmatic surface of the heart? A.Posterior boarder B.Left boarder C.Inferior boarder D.Right boarder Answer 1. The correct answer is A. Epicardium. It is the outermost layer of the heart and provides protection and support for the heart. 2. The correct answer is C. Fibrous pericardium. It is composed of dense irregular connective tissue and forms the tough outermost layer of the pericardium. 3. The correct answer is D. Pericardial (serous) fluid. This fluid is secreted by the serous pericardium and acts as a lubricant, reducing friction between the layers of the heart. 4. The correct answer is A. Epicardium. It is the outermost layer of the heart and is composed of mesothelial cells and connective tissue. 5. The correct answer is E. Auricle. The auricle is an extension of the atrium and helps to increase its capacity. 6. The correct answer is C. Myocardium. This layer is composed of cardiac muscle tissue and is responsible for the contraction of the heart. 7. The correct answer is C. Posterior interventricular sulcus. This sulcus marks the boundary between the ventricles on the back surface of the heart. 8. The correct answer is A. Pectinate muscles. These are muscular ridges that are found in the atria and extend into the auricles. 9. The correct answer is C. Tricuspid valve. This valve is located between the right atrium and right ventricle and allows blood to flow from the atrium to the ventricle. 10. The correct answer is C. Areolar connective tissue. This type of tissue makes up the valves of the heart. 11. The correct answer is B. Foramen ovale. This opening connects the right and left atria in a fetus and allows blood to bypass the lungs. 12. The correct answer is B. Into the apex. The apex is the pointed end of the heart and is where blood is ejected from the ventricles. 13. The correct answer is A. Into an auricle. The auricles are extensions of the atria and help to direct blood flow into the ventricles. 14. The correct answer is C. Pulmonary valve. This valve is located between the right ventricle and pulmonary trunk and prevents blood from flowing back into the right ventricle. 15. The correct answer is D. Aortic stenosis. In this disorder, the aortic valve becomes narrow and restricts blood flow. 16. The correct answer is A. Coronary artery. These are the vessels that supply oxygenated blood to the heart muscle. 17. The correct answer is C. Gap junctions. These are specialized connections between cardiac muscle cells that allow for rapid electrical signal transmission. 18. The correct answer is C. Cardiac muscle. Cardiac muscle cells have a high demand for energy and therefore contain a large amount of mitochondria. 19. The correct answer is D. Conduction system. This specialized network is responsible for coordinating the electrical signals that regulate the contractions of the heart. 20. The correct answer is B. A longer. The contraction plateau time in cardiac muscle is longer than that of skeletal muscle due to the sustained contraction needed to maintain blood flow. 21. The correct answer is A. Cardiac output. This is the volume of blood ejected from the left ventricle into the a Question 5 Where do you locate the stratified squamous epithelium: non-keratinized in the human body? Answer The stratified squamous epithelium: non-keratinized can be found in multiple locations throughout the human body, serving a variety of functions. It is commonly found lining the oral cavity, esophagus, vagina, and anal canal, as well as in the anterior surface of the eye. In the oral cavity, it serves as a protective barrier against mechanical stress and chemical irritants. In the esophagus, it helps with the movement of food through the digestive tract. In the vagina and anal canal, it provides protection against abrasion and infection. In the anterior surface of the eye, it plays a role in maintaining the integrity of the cornea. Question 6 8.These extend into the auricle. A.Pectinate muscles B.Interatrial septum C.Coronary sulcus D.Ventricle E.Chordae tendinae 9.Through which structure does blood pass from the right atrium to the right ventricle? A.Bicuspid valve B.Interventricular septum C.Tricuspid valve D.Mitral valve E.Ascending aorta 10.What types of tissue comprise the valves of the heart? A.Dense regular connective tissue B.Dense irregular connective tissue C.Areolar connective tissue D.Hyaline cartilage E.Cardiac muscle tissue 11.This structure temporarily shunts blood from the pulmonary trunk into the aorta in a fetus. A.Fossa ovalis B.Foramen ovale C.Trabeculae carnae D.Descending aorta E.Ductus arteriosus 12.As each ventricle contracts, where does blood move? A.Into an artery B.Into the apex C.Into a vein D.Through an atrioventricular valve E.Through the apex 13.As each atrium contracts, where does blood move? A.Into an auricle B.Into an artery C.Into a vein D.Through an atrioventricular valve E.Through a semilunar valve 14.Which of the below structures prevents blood from flowing back from the lungs? A.Tricuspid valve B.Bicuspid valve C.Pulmonary valve D.Aortic valve E.Pulmonary vein 15.In this disorder, the aortic valve is narrowed. A.Aortic insufficiency B.Rheumatic fever C.Mitral valve prolapse D.Aortic stenosis E.Aortic regurgitation 16.This vessel distributes oxygenated blood to the myocardium. A.Coronary artery B.Coronary vein C.Right ventricle D.Left auricle E.Myocardial vein 17.Cardiac muscle fibers electrically connect to neighboring fibers by A.Desmosomes B.Intermediate discs C.Gap junctions D.Contractile fibres E.Chordae tendinae 18.Which of the following contains the largest amount of mitochondria? A.Smooth muscle B.Skeletal muscle C.Cardiac muscle D.Hepatocytes E.Leukocytes 19.This is a network of specialized cardiac muscle fibers that provide a path for each cycle of cardiac excitation to progress through the heart. A.Pacemaker B.Sinoatrial node C.Purkinje fibres D.Conduction system E.Bundle of His 20.By comparison, cardiac muscle cells have _____________________ contraction plateau time than skeletal muscle cells. A.A shorter B.A longer C.No difference in 21.This is the volume of blood ejected from the left ventricle into the aorta each minute. A.Cardiac output B.Cardiac input C.Stroke volume D.Heart rate E.Auscultation 22.This term refers to the period during a cardiac cycle when contraction occurs and blood pressure rises. A.Filling B.Systole C.Repolarization D.Diastole E.Fibrillation 23.Which of the following heart chamber has thickest muscle layer? A.Right atrium B.Right ventricle C.Left ventricle D.Left atrium 24.Epicardium is closely attached with? A. Fibrous layer of pericardium B. Endocardium C. Parietal pericardium D. Visceral pericardium 25.Mitral valve is also known as? A.Aortic valve B.Bicuspid valve C.Pulmonic valve D.Tricuspid valve 26.What is the approximate weight of the heart of an adult person? A.550 g B.250 g C.325 g D.750 g 27.A groove or slight depression seen on external surface of the heart is known as? A.Atrio septal groove B.Cristae terminalis C.Sulcus terminalis D.Septum 28.How many papillary muscles are there in right side of the heart? A.1 B.3 C.2 D.5 29.Pericardial fluid is lubricating fluid seen in between? A.Parietal pericardium and fibrous pericardium B.endocardium and myocardium C.visceral pericardium and parietal pericardium D.myocardium and epicardium 30.Which boarder of the heart is known as diaphragmatic surface of the heart? A.Posterior boarder B.Left boarder C.Inferior boarder D.Right boarder Answer 8. The extend into the auricle is known as A. Pectinate muscles. This intricate and mesh-like muscle structure can be found lining the inner wall of the right and left atria, extending into the auricles. These muscles help to increase surface area in the atria, allowing for more effective contraction and blood flow. 9. The structure through which blood passes from the right atrium to the right ventricle is the C. Tricuspid valve. This valve has three cusps, or flaps, which allow blood to flow from the right atrium into the right ventricle, but prevent backflow into the atrium. 10. The valves of the heart are comprised of A. Dense regular connective tissue. This type of tissue is known for its strength and ability to withstand tension, making it well-suited for the constant opening and closing of the heart valves. In addition to connective tissue, the valves also contain a layer of endothelium, a specialized epithelial tissue that provides a smooth surface for blood flow. 11. The structure that temporarily shunts blood from the pulmonary trunk into the aorta in a fetus is the E. Ductus arteriosus. This structure is a connection between the pulmonary trunk and the aorta, allowing oxygenated blood from the mother to bypass the lungs and circulate to the rest of the body. After birth, the ductus arteriosus typically closes, becoming a ligament. 12. As each ventricle contracts, blood moves B. Into the apex. The apex, or pointed end, of the heart is where the ventricles are located. As they contract, blood is pushed out of the ventricles and into the corresponding arteries, which then distribute blood to the rest of the body. 13. As each atrium contracts, blood moves D. Through an atrioventricular valve. The atria contract to push blood into the ventricles, but before it can do so, it must pass through the atrioventricular valves, which separate the atria from the ventricles. 14. The structure that prevents blood from flowing back from the lungs is the C. Pulmonary valve. This valve is located between the right ventricle and the pulmonary trunk, and helps to ensure that blood only flows in one direction - from the right ventricle to the lungs.