Question 1

Which of the following results from cell fragmentation?

Accepted Answer

Platelets are the cells found in blood which helps in the clotting of the blood. The formation of platelets takes place in bone marrow from large bone marrow cells known as megakaryocytes. These cells after becoming mature enough, undergo the process of cell fragmentation to produce platelet cells. The hormone that help in platelet production is thrombopoietin. So, the correct answer is D.

Question 2

A matured mammalian RBC is unusual because:

Accepted Answer

Mammalian erythrocytes are unique among the vertebrates as they are non-nucleated cells in their mature form. These cells have nuclei during early phases of erythropoiesis, but extrude them during development, as they mature in order to provide more space for haemoglobin.Thus, the correct answer is option C.

Question 3

................. manufactures antibodies.

Accepted Answer

WBCs or the white blood cells are the types of blood cells that are main cells of the immune system. The immune system responds to a particular pathogen to give you active or acquired immunity. The surface of every cell is covered with molecules that give it a unique set of characteristics. These molecules are called antigens. Antigens are generally fragments of protein or carbohydrate molecules. There are millions of different antigens and each one has a unique shape that can be recognized by the white blood cells of your immune system. The white blood cells then produce antibodies to match the shape of the antigens. Thus, option B is correct.

Question 4

Certain compounds released by the WBCs, raise the body temperature. These compounds are known as:

Accepted Answer

Pyrogens are substances that induce fever. These can be internal (endogenous) or external (exogenous) to the body. The bacterial substance, lipopolysaccharide or LPS, present in the cell wall of some bacteria is an example of an exogenous pyrogen.Histamine is an organic nitrogenous compound involved in local immune responses.Toxins are compounds producing toxins. These toxins interfere with the metabolism and make the cell wall porous.Pathogens are infectious agents that activate the immune response. So, the correct answer is option A.

Question 5

Which of the following is not a function of lymph node?

Accepted Answer

Lymph is a watery, clear fluid because it lacks red blood cells (erythrocytes). It consists of plasma and white blood cells (leucocytes) only. Lymph nodes contain numerous lymphocytes which produce antibodies to trap the foreign particles. This main function is to destroy foreign particles and provide immunity to the body.So, the correct answer is option 'Store RBC'.

Question 6

The principle function of the lymph node in human body is:

Accepted Answer

Lymph nodes contain numerous lymphocytes which produce antibodies to destroy the foreign pathogens. Thus, the main function of lymph nodes is to destroy the foreign pathogens and provide immunity to the body.So, the correct answer is option C.

Question 7

The lymphatic system serves to:

Accepted Answer

The lymphatic system returns excess interstitial fluid to the blood. Of the fluid that leaves the capillary, about 90 percent is returned. The 10 percent that does not return becomes part of the interstitial fluid that surrounds the tissue cells. Thus, the fluid volume in the interstitial compartment is kept constant.

Question 8

Fats and lipids are absorbed in:

Accepted Answer

Fatty acids and glycerol being insoluble, cannot be absorbed into the blood. They are reformed into very small protein-coated fat globules called the chylomicrons, which are transported into the lymph vessels (lacteals) in the villi. These lymph vessels ultimately release the absorbed substances into the bloodstream.

Question 9

Mixing up of arterial and venous blood does not take place in a___________ heart.

Accepted Answer

A heart with four chambers has two atria and two ventricles.Here the right ventricle pumps the oxygen-poor blood to the lungs and the left atrium receives oxygen-rich blood from the lungs and pumps it to the left ventricle. The left ventricle pumps oxygen-rich blood to the body.The right side of the heart is separated from the left side due to the presence of the septum.Hence, option  B is correct.

Question 10

In a normal human, the amount of blood pumped by the heart per minute is approximately:

Accepted Answer

In a normal human, the amount of blood pumped by the heart per minute is 5 litres. It can be calculated based on the heart rate which is defined as heartbeats per minute (72 beats a minute) and a stroke volume which is defined as the volume of blood pumped by one ventricle with each heartbeat (which is 70 ml per beat). Therefore, the average amount of blood pumped by the heart = 70*72 ml =~5 litres. Thus, the correct answer is option B.

Question 11

The atrial wall is ________, while the ventricular wall is _______.

Accepted Answer

Our heart has four chambers, two relatively small thin-walled upper chambers called atria. These receive oxygenated blood (left atrium) and deoxygenated blood (right atrium). These are the 'receiving chambers'.The atria pour the blood received by them into the respective ventricle. Ventricles are thick-walled as they have to pump blood. The right ventricle pumps blood into the pulmonary artery while the left ventricle pumps blood into the aorta. So, the correct answer is 'thin, thick'.

Question 12

In the heart of mammals, the bicuspid valve is situated between:

Accepted Answer

The bicuspid valve is also known as the mitral valve. It is situated between the left atrium and left ventricle. It prevents the backflow of the blood from the left ventricle to the left atrium. It has 2 flaps. Hence, known as bicuspid.

Question 13

Choose the correct alternative in the following statements.Pulmonary vein carries:

Accepted Answer

The pulmonary vein carries oxygenated blood from the lungs back to the left atrium of the heart. It is the part of the pulmonary circulation.Hence, the correct answer is 'Oxygenated blood'.

Question 14

For reaching left side of the heart from the right side, blood must pass through:

Accepted Answer

Deoxygenated blood reaches the right side of the heart from the systemic circulation.From there it is carried to the lungs for oxygenation. The oxygenated blood is carried from the lungs to the left side of the heart via pulmonary veins. From the left side of the heart, the oxygenated blood is pumped into the systemic circulation again.

Question 15

The blood vascular system of mammals is known as the double vascular system because:

Accepted Answer

Double circulation in a four-chambered heart means that two circulations are acting together in the cardio-respiratory system simultaneously. One circulation is from the right ventricle to the lungs and back to the left atrium after oxygenation of the blood.The other circulation is from the left ventricle to the entire systemic circulation and back to the right atrium (oxygenated blood). In normal cases, the oxygenated and the de-oxygenated systems never mix.So, the correct answer is option D.

Question 16

All arteries carry oxygenated blood except:

Accepted Answer

All arteries carry oxygenated blood except pulmonary artery.The pulmonary artery is the artery that carries blood from the heart to the lungs. It carries deoxygenated blood from the heart to the lungs where it gets oxygenated.So, the correct answer is 'Pulmonary'.

Question 17

Purkinje fibres are special types of:

Accepted Answer

Purkinje fibres are specialized muscle fibres located in the inner ventricular walls of the heart. They help in the spread of impulses from the Bundle of His to the ventricles of the heart.

Question 18

Bundle of His is a network of:

Accepted Answer

Solution&#10;&#10;Correct answer is option C.Explanation for correct&#10;option:'Bundle of His' is a&#10;network of muscle fibres, found in the walls of ventricles. They originate from&#10;AV node and further give rise to Purkinje fibres.The bundle of His is a&#10;part of the electrical system of the heart. It is a collection of&#10;cells that carry electrical signals from the AV node to the bundle branches.&#10;&#10;&#10;&#10;&#10;&#10;&#10;&#10;

Question 19

The nerve impulse travels to bundle of His from:

Accepted Answer

The bundle of His arises from AV node and transmits the electrical impulses from AV node to the ventricles of the heart via Purkinje fibres. So, the correct answer is option B.

Question 20

Impulse originating from SA node is transmitted to:

Accepted Answer

B. AV nodeReason: The SA node (sinoatrial node) generates the impulse for the heartbeat.&#10;This impulse is then conducted to the atrioventricular node. The path followed by the impulse is from the SA node to the AV node to  Bundle of His to the Purkinje system.

Question 21

In an amphibian, the heart has:

Accepted Answer

In the amphibian heart, there are 2 atria and one ventricle. The right atrium receives deoxygenated blood and the left atrium receives oxygenated blood. When the atria contract, the left and right atrium empty their blood into the ventricle. Next the ventricle contracts and pumps the blood into one large blood vessel, which divides into smaller blood vessels in the amphibian's body. Some of the blood mixes together.

Question 22

The heart of a crocodile consists of:

Accepted Answer

Crocodile has a four-chambered heart. Two atria, two ventricles, and left and right aorta, which are connected by a hole called the Foramen of Panizza.

Question 23

Which of the following has a 3-chambered heart?

Accepted Answer

Vertebrates have evolved a muscular heart to pump blood to body parts. Fishes have a two-chambered heart. Birds and mammals have four-chambered hearts, having two atria and two ventricles. Reptiles, except crocodile, have a three-chambered heart. Crocodiles have a four-chambered heart. Thus Dolphin being a mammal has a four-chambered heart. Salamander being an amphibian has a three-chambered heart.

Question 24

Single heart circuit occurs in:

Accepted Answer

All vertebrates possess a muscular chambered heart. Fishes have a 2-chambered heart with an atrium and a ventricle. Amphibians and the reptiles (except crocodiles) have a 3-chambered heart with two atria and a single ventricle, whereas crocodiles, birds and mammals possess a 4-chambered heart with two atria and two ventricles. In fishes, the heart pumps out deoxygenated blood, which is oxygenated by the gills and supplied to the body parts from where deoxygenated blood is returned to the heart (single circulation).

Question 25

An ECG gives information of:

Accepted Answer

Electrocardiogram (ECG) is a test that records the heart's electrical activity. ECG is used to detect and study many heart problems, such as heart attacks, arrhythmias and heart failure along with other disorders that affect heart function.

Question 26

The condition which cannot be detected by ECG is:

Accepted Answer

As each wave of contraction spreads through the heart, electric currents flow into the tissues surrounding the heart and onto the body surface. By placing electrodes on the body surface on opposite sides of the heart, a physician can amplify and record the electrical activity. The graph produced is called an electrocardiogram (EKG or ECG). Abnormalities in the EKG indicate disorders in the heart or its rhythm. For example, in heart block, impulse transmission is delayed or blocked at some point in the conduction system. Artificial pacemakers can help patients with severe heart block. The pacemaker is implanted beneath the skin and its electrodes connected to the heart. This device provides continuous rhythmic impulses that avoid the block and drive the heartbeat. Angina (pain in chest) and defects in heart valve can also be detected through an abnormal ECG. Ulcers in stomach or Gastric ulcers cannot be detected by an ECG.

Question 27

ECG depicts the depolarisation and repolarisation processes during the cardiac cycle. In the ECG of a normal healthy individual one of the following waves is not represented.

Accepted Answer

Correct option: B Explanation:The P  wave in ECG complex indicates atrial depolarization and the QRS is responsible for ventricular depolarization. In ECG T wave is showing ventricular repolarization. In ECG repolarization of atria didn't showing by any wave.

Question 28

The first negative wave in ECG is:

Accepted Answer

The waves represent the flow of energy between two electrodes. Depending on which lead the ECG is viewed, it will determine whether the wave is negative or positive. The first deflection is the P wave associated with right and left atrial depolarization. It is a very minimal deflection from the baseline which is hardly detected.The first negative deflection is the Q wave. Normal Q waves represent septal depolarization. The first positive deflection is termed an R wave. The R wave represents depolarization of the left ventricular myocardium. T wave represents repolarization of ventricles. It is a positive deflection.So, the correct answer is 'Q'.

Question 29

Angina pectoris is a major symptom of:

Accepted Answer

Myocardial infarction is the technical term for heart attack.The main symptoms of angina pectoris are chest pain, which feels like a heart attack with pressure or squeezing in the chest. Therefore, angina pectoris is a symptom of myocardial infarction.So, the correct answer will be option A.

Question 30

Congenital heart disease is:

Accepted Answer

Congenital heart disease refers to the problem in the structure of the heart that is present at birth. It can be related to the wall of the heart, the valves of the heart and the arteries and veins associated with the heart. The presence of Foramen Ovale is an example of congenital heart disease in which the septal wall between the right and the left atrium is not formed.Hence, the correct answer is 'a problem in the structure of the heart that is present at birth'.

Question 31

Thickening of arteries due to cholesterol deposition is known as:

Accepted Answer

Atherosclerosis refers to the buildup of fats, cholesterol and other substances in and on your artery walls (plaques), which can restrict blood flow. Arteriosclerosis occurs when the blood vessels that carry oxygen and nutrients from your heart to the rest of your body (arteries) become thick and stiff, sometimes restricting blood flow to your organs and tissues. Healthy arteries are flexible and elastic but over time, the walls in your arteries can harden, a condition commonly called as hardening of the arteries.

Question 32

Myocardial infarction is caused by _______________.

Accepted Answer

A heart attack occurs when one of the heart's coronary arteries is blocked suddenly or has extremely slow blood flow. A heart attack also is called a myocardial infarction. The usual cause of sudden blockage in a coronary artery is the formation of a blood clot.So, the correct answer is clot may occur in the lumen of coronary artery.

Body Fluids And Circulation