MCQExams
0:0:1
CBSE
JEE
NTSE
NEET
Practice
Homework
×
CBSE Questions for Class 11 Medical Biology Body Fluids And Circulation Quiz 14 - MCQExams.com
CBSE
Class 11 Medical Biology
Body Fluids And Circulation
Quiz 14
Which of the following is responsible for coagulation of blood?
Report Question
0%
RBCs
0%
WBCs
0%
Platelets
0%
Plasma
Explanation
The platelets also called thrombocytes are round in shape and the smallest in size.
The platelets help in clotting of blood which prevents excessive blood loss and direct entry of disease causing germs into the blood through cuts and wounds.
Thus, these are responsible for coagulation of blood. Option C is correct.
Function of WBCs is to
Report Question
0%
Transport oxygen.
0%
Help in the clotting of blood.
0%
Provide immunity.
0%
Provide storage of food.
Explanation
White blood cells helps in providing immunity.
Red blood cells helps in transporting oxygen
Blood platelets help in the clotting of blood.
Fat cells provide storage of food.
Thus, the correct answer is (C).
The most abundant tissue of the adenoid tonsils is
Report Question
0%
Epithelium
0%
Reticular connective tissue
0%
Elastic connective tissue
0%
Plasma
Explanation
The tonsils are small, rounded masses of lymphoid tissue located in the lamina propria of the pharyngeal wall.
Lymphoid tissue of the tonsils is made up of free cells, with a rich framework of reticular type III collagen fibres supporting the cells. These fibres are maintained by reticular cells.
So, the correct answer is option B.
The diagram above shows, how things get to and from the liver. They are labelled as A,B,C,D, E and F. Which one of the following labelled as the correct one?
Report Question
0%
A is the hepatic portal vein and E is the hepatic vein.
0%
C is the intestine and F is the hepatic portal vein.
0%
D is the hepatic portal portal vein and F is the hepatic vein.
0%
B is the pancreatic artery and E is the hepatic artery.
0%
B is the hepatic portal vein and E is the hepatic vein.
Explanation
The hepatic portal vein is a vessel that moves blood from the spleen and gastrointestinal tract to the liver's capillary beds. Its functions are to supply metabolic substrates to the liver and to maintain that ingested substances are first processed by the liver before entering normal circulation. Hepatic veins are blood vessels which transport the liver's deoxygenated blood to the inferior vena cava. The hepatic veins originate in the liver lobule's central vein.
In the centre of each hepatic lobule lies
Report Question
0%
Portal vein
0%
Central vein
0%
Central artery
0%
Bile duct
Explanation
The liver is organized into lobules which take the shape of polygonal prisms. Each lobule is hexagonal in cross section and is centered on a branch of the hepatic vein called the central vein.
So, the correct answer is option B.
The portal system seen in all vertebrates is
Report Question
0%
Hepatic
0%
Renal
0%
Pulmonary
0%
Both A and B
Explanation
The system which directs the blood from the gastrointestinal tract to the liver before entering the heart is known as portal system. It starts and end with the capillaries.
The portal system of liver is known as hepatic portal system.
It carries the nutrient rich blood from the visceral parts to the liver for processing. Liver removes the toxic substances from the blood.
The portal system in the kidney is known as renal portal system. It is formed by the union of femoral and sciatic nerve. It opens into the kidney by capillaries. Kidney removes the metabolic waste from the blood of the portal system.
So, the correct answer is option D.
Which one of the following is a matching pair of a certain body feature and its value/ amount in a normal human adult?
Report Question
0%
Urea- 5-10 mg/l00mL of blood
0%
Blood sugar (fasting)- 70-100 mg/100ml
0%
Total blood volume- 5-6
0%
ESR in Wintrobe method- 9-15 mm in males and 20-34 mm in females
Explanation
The liver produces urea in the urea cycle as a waste product of the digestion of protein. Normal adult blood should contain 6-20 mg of urea nitrogen per 100 ml of blood i.e., 6-20mg/dl per 100 ml of blood. So, option A is correct.
A normal fasting (no food for eight hours) blood sugar level is between 70 - 100 mg/dl. So, option B is correct.
Blood volume is the volume of blood, both RBCs and plasma in the circulatory system of any individual. A typical adult has a blood volume of approximately 4.7-5 liters. So, option C is incorrect.
ESR is erythrocyte sedimentation rate is the rate at which RBC sediment in a period of one hour. That value in men is from 12-19 mm/hour while in females is 18-23 mm/hr. So, option D is also incorrect.
Thus, the correct answer is option (B), 'Blood sugar (fasting) -70-100 mg/100ml'.
Which of the following protein is responsible for spontaneous blood clotting?
Report Question
0%
Factor XII
0%
Factor XI
0%
Factor IX
0%
Factor VIII
Explanation
Factor VIII is an important blood clotting protein, which is also known as anti-haemophilic factor (AHF), encoded by the F$$_{8}$$ gene.
Factor VIII circulates in the bloodstream in an inactive form, bound to another molecule, called Von Willebrand factor, until an injury that damages the blood vessels occurs. When injury occurs, the factor VIII is activated and separates from Von Willebrand factor. The active protein interacts with another coagulation factor, called factor IX. This interaction leads to a chain of additional reactions, that form a blood clot.
Which one of the following mammalian cells is not capable of metabolizing glucose to carbon dioxide aerobically ?
Report Question
0%
Red blood cells
0%
White blood cells
0%
Unstriated muscle cells
0%
Liver cells
Explanation
RBCs of mammalian cells at maturity lose all the organelles and the space is replaced by haemoglobin. So it does not contain mitochondria and the oxidative enzymes of mitochondria to carry out the Krebs cycle. It instead uses EMP and hexose monophosphate shunt to anaerobically breakdown glucose to release ATP
So, the correct answer is '
Red blood cells'
Which of the following blood vessels does not carry any carbon dioxide?
Report Question
0%
Pulmonary artery
0%
Vena cava
0%
Hepatic vein
0%
Pulmonary vein
Explanation
There are two types of blood vessels such as arteries and veins. Arteries carry oxygenated blood from the heart to other body parts except for pulmonary artery that carries deoxygenated blood from the heart to lungs. Veins carry deoxygenated blood from other parts of the body to the heart except for pulmonary vein that carries oxygenated blood from lungs to the heart. Thus, the correct answer is option D.
In the clotting mechanism pathway, thrombin activates factor
Report Question
0%
XI, VIII, V
0%
XI, IX, X
0%
VIII, X, V
0%
IX, VIII, X
Explanation
Thrombin is a serine protease, that in humans is encoded by the F$$_{2}$$ gene. Thrombin is obtained by the proteolytic cleavage of prothrombin in the coagulation cascade which results in reduction of blood loss. Thrombin now acts as a serine protease that converts soluble fibrinogen to insoluble strands of fibrin and also catalyzes many other coagulation related reactions. So, once activated, thrombin acts to convert factor XI to XIa, VIII to VIIIa, fibrinogen to fibrin, V to Va and XIII to XIIIa.
Thus, the correct answer is option (A).
Blood platelets help in the blood coagulation mechanism by liberation of
Report Question
0%
Thromboplastin
0%
Thrombin
0%
Prothrombin
0%
None of the above
Explanation
Thromboplastin is a plasma protein aiding blood coagulation through catalyzing the conversion of prothrombin to thrombin. It is a complex enzyme that is found in brain, lung, and other tissues and especially in blood platelets and that functions in the conversion of prothrombin to thrombin in the clotting of blood, called as thrombokinase.
Blood platelets are formed from:
Report Question
0%
Thrombocytes
0%
Megakaryocytes
0%
Leucocytes
0%
Erythroblasts
Explanation
Circulating blood platelets are specialized cellular fragments, that prevent bleeding and minimize blood vessel injury. Large progenitor cells in the bone marrow, called megakaryocytes are the source of platelets.
In humans, blood passes from the post caval to the diastolic right atrium of heart due to
Report Question
0%
Pushing open of the venous valves
0%
Suction pull only
0%
Stimulation of the sino-auricular node
0%
Pressure difference between the post caval and atrium and suction pull
Explanation
Hemodynamically, venous return (VR) to the heart from the venous vascular beds is determined by a pressure gradient (venous pressure - right atrial pressure) and venous resistance (RV). Therefore, increases in venous pressure or decreases in right atrial pressure or venous resistance will lead to an increase in venous return. In diastole, the pressure in the right atrium decreases than the postcaval vein. Hence, blood flows from post caval into the right atrium through suction pull.
The absence of which clotting factor leads to haemophilia- A?
Report Question
0%
Factor - VII
0%
Factor - VIII
0%
Factor - IX
0%
Factor - X
Explanation
Haemophilia A is an X- linked recessive disorder which is caused by the deficiency of blood plasma clotting factor VIII. It can be genetic or arise due to a mutation.
It is necessary to separate oxygenated blood from the deoxygenated blood in mammals:
Report Question
0%
To maintain the body temperature
0%
To provide more oxygen to cells
0%
Both A and B
0%
To maintain body balance
Explanation
In birds and mammals, it is essential to keep the oxygenated blood separated from the deoxygenated blood.
Birds and mammals are warm-blooded animals. Their energy requirement is high as they need the energy to maintain constant body temperature.
By keeping them separate, only oxygenated blood is sent out to the body's tissues for far more efficient diffusion into the cells of the body, giving them more 'fuel' to run cellular respiration in the mitochondria, to make ATP molecules run the reactions that allow them to maintain body temperature in addition to running all of their metabolic reactions of the body.
If they were not separated, it would probably take much longer to perform simple activities and metabolism would be reduced as a consequence.
So, the correct answer is option C.
A man was infested with germs and was taken to the hospital. On pathological tests, it was found that he had
a. A low number of RBC
b. A high number of WBC and a low number of RBC
c. A low number of WBC
d. A high number of platelets
Which of the following alternative is correct?
Report Question
0%
b only
0%
a and d
0%
c only
0%
d only
Explanation
White blood cells (WBCs) are cells of the immune system involved in defending the body against both infectious diseases and foreign materials. Therefore, an abnormally high of WBC may agree with the suspicion that an infection is present and the doctor will order further tests.
An abnormally low level of RBC may signal to the physician that the patient may be suffering from anemia, which might have caused by any intestinal worm infestation, like Hookworm.
Although total WBC count falls in viral infections, viruses are not considered as germs, which have infected the subject (man).
Bacterial or viral infections are the most common causes of a high white blood cell count. The increase in white blood cells due to infection is caused by a normal response of the immune system triggering the bone marrow to release additional stored white blood cells into the blood to fight off the disease. Low level of RBC may result in reduced immunity.
Hence A is the correct option.
Thromboplastin is secreted by
Report Question
0%
Platelets
0%
Lymphokines
0%
Helper T cells
0%
Mast cells
Explanation
Thromboplastin is secreted by the platelets. It is a plasma protein which aids in blood coagulation through catalyzing the conversion of prothrombin to thrombin. It is a complex enzyme, that is found in brain, lung, and other tissues and especially in blood platelets and that functions in the conversion of prothrombin to thrombin in the clotting of blood. It is also called thrombokinase.
The RBCs of the camel are:
Report Question
0%
Circular, convex and non-nucleated
0%
Circular, convex and nucleated
0%
Oval and non-nucleated
0%
Oval and nucleated
Explanation
The red blood cells of camel are oval-shaped and they also have a nucleus in them, unlike in other mammals, where the RBCs are circular and enucleated. The oval shape helps to facilitate their flow in a dehydrated state. These cells are also more stable in order to withstand high osmotic variation without rupturing when drinking large amounts of water. Thus, the correct answer is option D.
Which of the following statements is related to Starling's law of heart?
Report Question
0%
Greater the stroke volume, greater is the heart rate.
0%
Greater the initial length of the cardiac muscle fibre, more is the force of contraction of heart.
0%
Greater the minute volume, greater is the heart rate
0%
Lesser the length of cardiac muscle fiber greater is the force of contraction of heart.
Explanation
Starling's law of the heart is also called Frank-Starling law or Frank-Starling law of the heart.
It states that the strength of the systolic contraction of the heart is directly proportional to its diastolic expansion. It gives the relationship between stroke volume and diastolic volume.
According to this law, the stroke volume of the heart increases with an increase in the blood volume of ventricles when all the other factors are kept constant.
Hence, the greater the stroke volume, the greater will be the heart rate.
Thus, the correct answer is option A.
EEG represents spontaneous
Report Question
0%
Electrical activity of brain recorded from the scalp
0%
Activity of pace maker
0%
Activity of alimentary canal
0%
None of the above
Explanation
Electroencephalography (EEG) is the recording of electrical activity along the scalp. EEG measures voltage fluctuations resulting from ionic current flows within the neurons of the brain.
Which artery supplies blood to the diaphragm?
Report Question
0%
Phrenic
0%
Splenic
0%
Renal
0%
Caudal
Explanation
The diaphragm is basically innervated by the
phrenic
nerve which is formed from the cervical nerves. The
diaphragm, therefore,
recieves
blood from the branches of the internal thoracic arteries and from the superior
phrenic
arteries.
The inferior phrenic arteries supply from below.
So, the correct answer is option A.
Critical count of platelet is
Report Question
0%
40, 000 / mm$$^3$$
0%
1 lac / mm$$^3$$
0%
2 lac / mm$$^3$$
0%
4 lac / mm$$^3$$
Explanation
Critical count of platelet is 40, 000 / mm$$^{3}$$. Platelets, also called thrombocytes, are blood cells whose function is to stop bleeding. Platelets have no nucleus: they are fragments of cytoplasm, which are derived from the megakaryocytes of the bone marrow, and then enter the circulation. These unactivated platelets are biconvex discoid structures. The normal number of platelets in the blood is 150,000 - 400,000 platelets per microliter (mcL).
A low platelet count is below 150,000. If the platelet count is below 50,000, the risk of bleeding is very high. So, it is called critical platelet count.
The animal cell which does not possess nucleus is
Report Question
0%
Egg of hen
0%
White blood cell
0%
Red blood cell
0%
Nerve cell
Explanation
All cells of egg of hen possess nucleus.
White blood cells possess multi-lobed nucleus at all life stages
Nerve cells has nucleus.
Red blood cell are most common type blood cell, they take up oxygen in the lungs and release it while squeezing through body's capillaries. During maturation, red blood cell loses nucleus. It enables the red blood cell to contain more oxygen carrying haemoglobin. This enables more oxygen to be transported by the red blood cell.
Blood circulation in insects is
Report Question
0%
Flows in arteries and veins
0%
With red blood corpuscles
0%
Open type
0%
Absent
Explanation
The blood circulatory system of insects is the open type where hemolymph flows freely within the body cavity or hemocoel. There are a heart and aorta but no capillaries and veins. The circulatory system consists of a body cavity or sinus, heart, and hemolymph. Thus, option C is correct.
Which one of the following anticoagulants is added in blood during storage?
Report Question
0%
Sodium carbonate
0%
Sodium oxalate
0%
Sodium chloride
0%
Sodium hydroxide
Explanation
Sodium oxalate
is the sodium
salt of oxalic acid
.
Sodium oxalate is
used to remove calcium ions
from blood plasma and prevents blood from clotting because calcium is used as a cofactor of enzymes for activation of clotting factors.
Hence, the correct answer is option B.
Mineral which helps in formation of RBCs is
Report Question
0%
Fe (iron)
0%
Mn (manganese)
0%
Mg (magnesium)
0%
K (potassium)
Explanation
A mineral which helps in the formation of RBCs is iron (Fe) because i
ron makes up the active part of
haemoglobin which
directly binds to and carries oxygen. If we don’t eat enough iron, we cannot produce enough
haemoglobin
to make functional red blood cells. Hence the correct option is A.
The renal portal system of vertebrates is significant for
Report Question
0%
Elimination of excess fats by kidneys
0%
Removing nitrogenous wastes in kidneys
0%
Supplying food to the kidneys
0%
Draining blood from the kidney
Explanation
When the vein of any organ of the body does not open in the caval vein or heart but it divides into capillaries in any other organ and its blood is transported by a vein of that other organ to heart then this type of system is called Portal system. It is of three types- Renal portal system, Hepatic portal system, Hypophysial portal system. The renal portal system comprises of veins which collect blood from posterior parts of body and legs and combines to form a renal portal vein. This vein goes into kidney and divides into capillaries. Kidneys separate nitrogenous wastes from this blood. This partly purified blood is now transported to the heart. This system is present in frog but absent in mammals.
So, the correct answer is option B.
Animal cell lacking nuclei would also lack in
Report Question
0%
Chromosome
0%
Ribosome
0%
Lysosome
0%
Endoplasmic reticulum
Explanation
Nucleus of a non-dividing cell contains chromatin which is uncoiled thread-like material of chromosome. Chromatin contains a DNA molecule and almost equal amount of basic histone proteins. Chromosomes occur during cell division and they are formed due to coiling and folding of chromatin. If any animal cell lacks nucleus then it will lack of chromosomes too.
When heart rate is > 200 beats/min. then which device is used for controlling the rhythm of heart?
Report Question
0%
Endoscopy
0%
Defibrillator
0%
Prosthetic cardiac pacemaker
0%
Oxygenator
Explanation
When the heart rate is > 200 beats/min. then a defibrillator is used for controlling the rhythm of the heart.
Defibrillation is a procedure used to treat life-threatening conditions that affect the rhythm of the heart such as cardiac arrhythmia, ventricular fibrillation, and pulseless ventricular tachycardia.
The procedure involves the delivery of an electric shock to the heart which causes depolarization of the heart muscles and re-establishes normal conduction of the heart’s electrical impulse. The machine used to deliver this therapeutic shock to the heart is called a defibrillator.
Endoscopy is a non-surgical procedure used to examine a person's digestive tract.
The sinoatrial node, known as the SA node is located in the right atrial wall below the opening of the superior vena cava. The SA node initiates the cardiac cycle and sets the basic pace for the heart rate, hence called the pacemaker.
If this normal and natural electrical stimulation of the heart fails, the conduction system is disrupted and heart blocks may result.
In patients with heart block, normal heart rate can be restored and maintained with an Artificial Pace Maker.
An oxygenator is a medical device that is capable of exchanging oxygen and carbon dioxide in the blood of a human patient during surgical procedures.
So, the correct answer is option B.
Tooth extraction in a person causes death due to excessive bleeding. This is because of
Report Question
0%
Absence of prothrombin
0%
Presence of plasma factor that causes haemorrhage
0%
Presence of plasma factor that prevents blood clotting
0%
Absence of plasma factor required for haemorrhage
Explanation
Prothrombin is a glycoprotein occurring in blood plasma and is an essential component of the blood-clotting mechanism. Prothrombin is transformed into thrombin by a clotting factor known as factor X or prothrombinase; thrombin then acts to transform fibrinogen, also present in plasma, into fibrin, which, in combination with platelets from the blood, forms a clot (coagulation). Under normal circumstances, prothrombin is changed into thrombin only when an injury occurs to the tissues or circulatory system or both; therefore, fibrin and blood clots are not formed except in response to bleeding.
Hypoprothrombinemia, a deficiency in prothrombin, is characterized by a tendency to prolonged bleeding. It is usually associated with a lack of vitamin K, which is necessary for the synthesis of prothrombin in the liver cells.
Removal of calcium from freshly collected blood will
Report Question
0%
Prevent clotting
0%
Result in clotting
0%
Prevent oxidation of haemoglobin
0%
Cause haemolysis
Explanation
Clotting requires calcium ions ($$Ca2^+$$), which is why blood banks use a chelating agent to bind the calcium in donated blood, so the blood will not clot in the bag.
Mammals are said to have double circulation, it means
Report Question
0%
Blood vessels are paired
0%
There are two types of blood vessels attached to every organ
0%
There are two systems
0%
The blood circulates twice through the heart
Explanation
Double circulation (double circulatory systems) are circulation systems in which blood flows through the heart twice. In the case of double circulation, pulmonary circulation - i.e., blood flow between the heart and lungs, is separate from systemic circulation - i.e., movement of blood from the heart through the rest of the body (excluding the lungs), then back to the heart. During one complete cycle of flow through the whole body (blood system), blood in a double circulatory system passes through the heart twice.
So, the correct answer is option D.
In a closed circulatory system, blood is completely enclosed with in
Report Question
0%
Sinuses
0%
Vessels
0%
Heart
0%
Skeleton
Explanation
In a closed circulatory system, blood is always contained within vessels - arteries, veins, capillaries.
Sodium oxalate prevents blood clotting due to
Report Question
0%
Blocking of fibrinogen transformation
0%
Covering RBC
0%
Inhibiting activity of clotting factor of plasma
0%
Combining with calcium ions of blood
Explanation
Sodium oxalate, like citrates, can be used to remove calcium ions (Ca$${^2}$$$${^+}$$) from blood plasma. It thus prevents blood from clotting. In the presence of calcium ions and other clotting factors, factor X activates an enzyme called prothrombin activator. This enzyme then converts the plasma protein prothrombin into thrombin. Thrombin is an enzyme that, in turn, converts fibrinogen to fibrin.
A mature human erythrocyte has the typical characteristic of
Report Question
0%
A eukaryotic cell
0%
A prokaryotic cell
0%
Both eukaryotic and prokaryotic cell
0%
Neither eukaryotic nor prokaryotic cell
Explanation
Mature human erythrocytes are eukaryotic cells, which have lost their nucleus and organelles. Initially, the RBCs have nucleus but lose it with maturation. Prokaryotic cells include bacteria and archaea bacteria. Prokaryotes are exclusively unicellular with a naked DNA, while erythrocytes (RBCs) are part of a multicellular organism. All eukaryotic cell has a nucleus, but RBC doesn't. So, they have properties of neither prokaryotes nor eukaryotes.
An open circulatory system occurs in the
Report Question
0%
Reptiles
0%
Birds
0%
Insects
0%
Annelids
Explanation
An open circulatory system describes a system where blood and interstitial fluid (fluid found between cells in the body) are allowed to mix in an organism. Organisms that have an open circulatory system don't have true blood since it is mixed with other fluids. The blood in these organisms is defined as haemolymph. Two of the largest phyla in the world, arthropoda and mollusca, have an open circulatory system. Arthropods include most insects and sea organisms like crabs and lobsters. Molluscs are organisms with two shells that are hinged together. Examples include clams and oysters. However, not all molluscs have an open circulatory system. Two major members of the mollusc family, octopus and squid, have a closed circulatory system.
Bicuspid and tricuspid valves are open during
Report Question
0%
Ventricular systole
0%
Ventricular diastole
0%
Atrial systole
0%
Late joint diastole
Explanation
Atrial systole occurs at the end of ventricular diastole. After the ventricle has pumped its blood, it begins to relax. There is now negative pressure in the ventricle (since it is now empty), and this pressure helps to draw in the blood from the atrium when it enters into systole. So during atrial systole, the bicuspid and tricuspid valves are open, and the pulmonary/aortic semilunar valves are closed. Then during the diastole, the bicuspid and tricuspid valves are closed.
Which statement(s) is/are not correct in context to connective tissues?
(i) Areolar connective tissue is found in bone marrow.
(ii) The ground substance of connective tissue is a mixture of carbohydrates and proteins only.
(iii) Lymph is a type of connective tissue.
(iv) Connective tissue acts as shock absorder around eye balls and kidneys.
Report Question
0%
(i) and (iii)
0%
(i), (ii) and (iii)
0%
Only (ii)
0%
Only (iv)
Explanation
The areolar tissue is a loose connective tissue that can be seen between the skin and muscles; in the bone marrow as well as around the blood vessels and nerves.
Connective tissue is made up of a matrix consisting of living tissue and a non-living substance. This non-living substance is called the ground substance.
The components of the ground substance of connective tissue are an organic substance, that is protein, and an inorganic substance, which is usually water or mineral.
Lymph is a type of fluid connective tissue like blood.
Adipose tissue is a type of connective tissue that keeps visceral organs in position. It forms shock-absorbing cushions around kidneys and eyeballs.
So, the correct answer is option C.
Blood doesn't clot in the absence of vitamin K because it is
Report Question
0%
An essential component of the clot
0%
An essential component of the platelets
0%
Essential for synthesis of prothrombin
0%
Essential for synthesis of fibrinogen
Explanation
Blood clotting factors are needed for blood to clot (coagulation). Prothrombin, or factor II, is one of the clotting factors made by the liver. Vitamin K is needed to make prothrombin and other clotting factors. So, blood does not clot in the absence of Vitamin K because it is essential for the synthesis of prothrombin and not because it is an essential component of the clot, platelets or essential for fibrinogen.
Thus, the correct answer is option C.
Which one is not the use of hepatic portal system?
Report Question
0%
To convert carbohydrate into glycogen.
0%
To separate ammonia.
0%
To kill bacteria.
0%
To convert protein into carbohydrate.
Explanation
The hepatic portal system is the system of blood vessels that connect the gastrointestinal system and the liver. The nutrients digested by the intestines are transported to the liver, where the excess of carbohydrates is converted into glycogen. The amino acids are broken down and ammonia is released, which is soon converted to urea through the Ornithine cycle. The liver has Kupffer cells that kill the bacteria before the nutrients move out to the different organs of the body.
Hence, the correct answer is 'To convert proteins into carbohydrates'
The given diagram shows a section through the human heart.
Identify the correct valve action and vessel through which blood passes to the lungs.
Report Question
0%
b closes 3
0%
b opens 4
0%
a closes 2
0%
a opens 1
Explanation
The tricuspid valve (a) is in the right side of the heart, between the right atrium and the right ventricle. The pulmonary valve is in the right side of the heart, between the right ventricle and the entrance to the pulmonary artery. The artery carries blood from the heart to the lungs. The mitral valve (b) is in the left side of the heart, between the left atrium and the left ventricle. When deoxygenated blood flows from the right ventricle through the pulmonary artery to the lungs, the tricuspid valve closes and the pulmonary valve opens.
So, the correct answer is option C.
Which of the following results from cell fragmentation?
Report Question
0%
RBC
0%
WBC
0%
Plasma
0%
Platelets
Explanation
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.
Which of the following should a heart patient firmly avoid?
Report Question
0%
Cream
0%
Mango
0%
Rice
0%
Milk
Explanation
Heart diseases can be caused due to a number of factors such as age, gender, tobacco use, physical inactivity, excessive consumption of alcohol, unhealthy diet, obesity, family history of cardiovascular disease, hypertension, diabetics, high cholesterol levels , psychosocial factors and pollution, However, a patient with any form of heart disease should avoid cream as intake of dietary trans fat tends to perturb the body's ability to metabolize the essential fatty acids which lead to changes in the phospholipid fatty acid composition of the main artery of the heart. This tends to increase the risk of coronary heart disease.
So, the correct answer is option A.
Life span of blood platelets in mammals is about _______.
Report Question
0%
3 days
0%
8 days
0%
1 month
0%
20 days
Explanation
Platelets are the smallest of the three major types of blood cells. Platelets are anuclear cytoplasmic fragments essential for blood clotting and wound healing. Blood platelets begin their lives as hematocytoblasts, or stem cells. Blood platelets have a life span of 8-10 days, at the end of which they undergo programmed cell death or apoptosis.
Hence, answer is '8 days'.
A schematic representation of the blood circulation is given. Which of the circulatory parts are incorrectly placed in it?
Report Question
0%
Right atrium and right ventricle
0%
Left atrium and left ventricle
0%
Pulmonary artery and pulmonary veins
0%
Aorta and vena cava
Explanation
The correct pathway is: Vena cava $$\rightarrow$$ Right atrium
$$\rightarrow$$
Right ventricle
$$\rightarrow$$
Pulmonary artery
$$\rightarrow$$
Lungs
$$\rightarrow$$
Pulmonary veins
$$\rightarrow$$
Left atrium
$$\rightarrow$$
Left ventricle
$$\rightarrow$$
Aorta
$$\rightarrow$$
Rest of the body.
Aorta is the main artery that carries oxygenated blood from the left ventricle of the heart towards the other parts of the body.
Vena cava collects deoxygenated blood from the body and pours the blood into the right atrium.
So, the correct answer is option D.
One of the factors required for the maturation
of erythrocytes is
Report Question
0%
Vitamin D
0%
Vitamin A
0%
Vitamin B$$_{12}$$
0%
Vitamin C
Explanation
Vitamin B$$_{12}$$
and folic acid (vitamin B$$_9$$) (both are members of the B vitamin complex) are important for the final maturation of RBC. This is because they are both important for the synthesis of DNA and diminished quantity of DNA leads to failure of nuclear maturation and division. The RBCs also become larger than normal (megaloblasts) which are fragile and have a short lifespan (they can carry oxygen normally).
Thus, the correct answer is option C.
Vitamin K is used for
Report Question
0%
Formation of prothrombin.
0%
Activation of prothrombin.
0%
Formation of fibrinogen.
0%
Formation of thromboplastin.
Explanation
Vitamin K is essential for the formation of factor VII, IX, X, and prothrombin. It is synthesized in the intestinal tract by bacteria. Blood coagulation or clotting takes place in 3 essential phases. The first phase is the activation of a prothrombin activator complex. The second phase is the activation of prothrombin. The third stage is clot formation as a result of fibrinogen cleavage by activated thrombin. Thus, its deficiency can result in excessive bleeding.
So, the correct answer is option A.
Number of RBC increases if one lives at higher altitude because
Report Question
0%
There is less oxygen
0%
More heat is required in body for producing body warmth.
0%
There are no germs in mountain air.
0%
There is more oxygen
Explanation
RBC count increases in people living at high altitudes because the atmospheric pressure decreases and the levels of atmospheric oxygen also falls. Hence to carry more amount of oxygen to the cells, more number of red blood cells are required.
Therefore the correct option is A.
One of the factors required for the maturation of erythrocytes is
Report Question
0%
Vitamin D
0%
Vitamin A
0%
Vitamin B$$_{12}$$
0%
Vitamin C
Explanation
Factors essential for the maturation of RBCs are vitamin B$$_{12}$$ (cobalamin) and vitamin B$$_9$$ (folic acid). Vitamin B
$$_{12}$$
works in conjunction with folate in the formation and maturation of red blood cells.
Therefore, the correct answer is option C.
0:0:1
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
0
Answered
0
Not Answered
0
Not Visited
Correct : 0
Incorrect : 0
Report Question
×
What's an issue?
Question is wrong
Answer is wrong
Other Reason
Want to elaborate a bit more? (optional)
Practice Class 11 Medical Biology Quiz Questions and Answers
<
>
Support mcqexams.com by disabling your adblocker.
×
Please disable the adBlock and continue.
Thank you.
Reload page
