What is the name of the blood vessel that carries deoxygenated blood from the body to the heart in a frog?
A.
Pulmonary vein
B.
Vena cava
C.
Aorta
D.
Pulmonary artery
Correct Answer: B
Explanation:
Frog's heart is a muscular structure with three chambers. It receives deoxygenated blood from body parts through the major veins called vena cava. Vena cava carries deoxygenated blood. Aorta and pulmonary vein carries oxygenated blood. Whereas, pulmonary artery will carry deoxygenated blood towards the lungs.
A person with blood group ARh– can receive the blood transfusion from which of the following types?
A. BRh$^–$
B. ABRh$^–$
C. ORh$^–$
D. ARh$^–$
E. ARh$^+$
Choose the correct answer from the options given below :
A.
D and E only
B.
D only
C.
A and B only
D.
C and D only
Correct Answer: D
Explanation:
The blood group of a person determines which antigens are present on the surface of their red blood cells and which antibodies are present in their plasma. In this case, ARh$^-$ implies that the person has A antigens on the surface of the red blood cells and does not have the Rh antigen (Rh-negative). Therefore, the person with ARh$^-$ blood can only receive blood from donors whose blood does not contain any antigens that their immune system would recognize as foreign and mount a response against.
For a person with ARh$^-$ blood, suitable donors would have:
1. A antigen (to match the recipient's A antigen) and be Rh-negative.
2. O blood group (which has no A/B antigens) and be Rh-negative.
Let's go through the options:
BRh$^-$: This blood group has B antigens, which would be recognized as foreign by the immune system of an A blood group recipient, hence it is not suitable.
ABRh$^-$: This blood group has both A and B antigens, which would also be recognized as foreign due to the presence of the B antigen, making it unsuitable.
ORh$^-$: This blood group has no A/B antigens, making it a universal donor for all ABO blood types and thus it is suitable for ARh$^-$ recipients.
ARh$^-$: This blood group matches perfectly with the recipient since it has the same A antigen and is Rh-negative.
ARh$^+$: This blood group has the A antigen but also has the Rh antigen (Rh-positive). The Rh antigen can trigger an immune response in someone who is Rh-negative, making this option unsuitable.
Renin from JG cell via switching off the osmoreceptors
B.
ANF from atria of the heart
C.
Aldosterone from adrenal medulla
D.
Vasopressin from Neurohypophysis
Correct Answer: D
Explanation:
The correct answer is Option D: Vasopressin from Neurohypophysis. Here's why:
Diuresis refers to increased urine production. Let's break down how each option affects urine production:
Option A: Renin from JG cells via switching off the osmoreceptors
Renin, released from the juxtaglomerular (JG) cells, is part of the renin-angiotensin-aldosterone system (RAAS). RAAS primarily affects blood pressure and volume by:
Increasing sodium reabsorption: This leads to water retention, thus increasing blood volume.
Constricting blood vessels: This raises blood pressure.
While RAAS can indirectly influence urine production, it doesn't directly prevent diuresis. Also, osmoreceptors are stimulated by increased blood osmolarity, not switched off by renin.
Option B: ANF from atria of the heart
Atrial natriuretic factor (ANF) is a hormone released from the heart's atria in response to high blood pressure. ANF acts to:
Decrease sodium reabsorption: This leads to increased urine output (diuresis) and lowers blood volume.
Dilate blood vessels: This lowers blood pressure.
Therefore, ANF actually promotes diuresis, not prevents it.
Option C: Aldosterone from adrenal medulla
Aldosterone is a hormone secreted by the adrenal cortex, not the medulla. Its primary function is to increase sodium reabsorption in the kidneys, leading to water retention and increased blood volume. This effect is opposite to diuresis.
Option D: Vasopressin from Neurohypophysis
Vasopressin, also known as antidiuretic hormone (ADH), is released from the posterior pituitary gland (neurohypophysis). Vasopressin plays a crucial role in regulating water balance by:
Increasing water reabsorption in the kidneys: This leads to concentrated urine and decreased urine output, preventing diuresis.
Vasopressin's action is the direct opposite of diuresis, making it the most effective in preventing excessive urine production.
In summary: Vasopressin (ADH) is the primary hormone responsible for preventing diuresis by increasing water reabsorption in the kidneys.
The correct answer is Option D: closure of the tricuspid and bicuspid valves. Here's why:
The "lub" sound of the heartbeat, known as the first heart sound (S1), is produced by the closure of the atrioventricular (AV) valves. These valves are the tricuspid valve (between the right atrium and right ventricle) and the bicuspid (mitral) valve (between the left atrium and left ventricle).
Here's a breakdown of the heart sounds and the events causing them:
S1 (Lub): Closure of the AV valves (tricuspid and bicuspid). This occurs at the beginning of ventricular contraction (systole) when the ventricles are pushing blood out.
S2 (Dub): Closure of the semilunar valves (pulmonary and aortic). This happens at the end of ventricular contraction when the ventricles are relaxing and filling with blood.
Let's look at why the other options are incorrect:
Option A: closure of the semilunar valves: This causes the "dub" sound, not the "lub" sound.
Option B: opening of tricuspid and bicuspid valves: This occurs during diastole (ventricular relaxation) and doesn't produce a significant heart sound.
Option C: opening of the semilunar valves: This happens at the beginning of ventricular contraction and is silent.
In summary, the "lub" sound of the heart is generated by the closure of the tricuspid and bicuspid valves as the ventricles contract and push blood into the aorta and pulmonary arteries.
Following are the stages of pathway for conduction of an action potential through the heart
A. AV bundle
B. Purkinje fibres
C. AV node
D. Bundle branches
E. SA node
Choose the correct sequence of pathway from the options given below
A.
E-C-A-D-B
B.
A-E-C-B-D
C.
B-D-E-C-A
D.
E-A-D-B-C
Correct Answer: A
Explanation:
The electrical pathway for the conduction of an action potential through the heart is a precisely coordinated process, essential for maintaining the heart's rhythmic beating. To understand this conduction pathway, it’s important to know the roles of the specific components involved:
SA node (Sinoatrial node): Often referred to as the pacemaker of the heart. It initiates the electrical impulse, causing the atria to contract.
AV node (Atrioventricular node): Receives the impulse from the SA node and provides a slight delay, allowing the ventricles time to fill with blood before they contract.
AV bundle (Bundle of His): Transfers the electrical impulse from the AV node to the bundle branches.
Bundle branches: Conducts the impulses through the interventricular septum.
Purkinje fibers: Distribute the electrical impulse throughout the ventricles, stimulating them to contract uniformly and powerfully.
The correct sequence for the pathway of an action potential through the heart follows a route designed to efficiently coordinate the heartbeat starting from the initiation of the action potential to the consequential contraction of the heart muscles. The sequence is:
SA node (E): The pacemaker where the electrical activity originates.
AV node (C): Where the impulse is delayed slightly.
AV bundle (A): Conducts the impulse from the AV node to the bundle branches.
Bundle branches (D): Leads the impulse to the Purkinje fibers.
Purkinje fibers (B): Distributes the impulse throughout the ventricles.
By examining the options provided with the above understanding:
Option A: E-C-A-D-B
Option B: A-E-C-B-D
Option C: B-D-E-C-A
Option D: E-A-D-B-C
Option A (E-C-A-D-B) correctly reflects the order in which the electrical impulse travels through the cardiac conduction system, beginning with the SA node and ending in the Purkinje fibers. Hence, Option A is the correct answer.
Choose the correct answer from the options given
below :
A.
A-(IV), B-(I), C-(III), D-(II)
B.
A-(I), B-(IV), C-(III), D-(II)
C.
A-(IV), B-(III), C-(I), D-(II)
D.
A-(III), B-(I), C-(IV), D-(II)
Correct Answer: D
Explanation:
An ECG (Electrocardiogram) is a test that measures the electrical activities of the heart. Each wave in an ECG represents a certain part of the heart's electrical activity:
P wave : This wave occurs prior to the contraction of the atria (atrial contraction). It represents the depolarization of the atria.
QRS complex : This is a series of three graph deflections seen on a typical electrocardiogram. It corresponds to the depolarization of the ventricles, which initiates the ventricular contraction.
T wave : The T wave represents the repolarization (or recovery) of the ventricles.
By matching these descriptions with the options provided :
(A) P-wave - Depolarisation of atria (III)
(B) QRS complex - Depolarisation of ventricles (I)
(C) T wave - Repolarisation of ventricles (IV)
(D) End of T wave - End of systole (II)
So, the correct answer seems to be Option D : A-(III), B-(I), C-(IV), D-(II)
Choose the correct answer from the options given
below :
A.
A-(IV), B-(I), C-(II), D-(III)
B.
A-(IV), B-(I), C-(III), D-(II)
C.
A-(II), B-(III), C-(IV), D-(I)
D.
A-(II), B-(III), C-(I), D-(IV)
Correct Answer: C
Explanation:
This question asks to match types of white blood cells (List I) with their usual proportion in the blood (List II). The correct matchings are :
Eosinophils (A) - typically make up 1-6% of white blood cells, so the best match is (I) 6 - 8%
Lymphocytes (B) - typically make up 20-40% of white blood cells, but none of the options are in this range. However, since the other cells have more fitting matches, the remaining percentage (III) 20 - 25% would be the best fit.
Neutrophils (C) - these are the most common type of white blood cells, making up 50-70% of all white blood cells, so the best match is (IV) 60 - 65%
Monocytes (D) - typically make up 2-8% of white blood cells, so the best match is (II) 2 - 3%
So, the correct answer is Option C : A-(I), B-(III), C-(IV), D-(II)
A. Basophils are most abundant cells of the total WBCs
B. Basophils secrete histamine, serotonin and heparin
C. Basophils are involved in inflammatory response
D. Basophils have kidney shaped nucleus
E. Basophils are agranulocytes
Choose the correct answer from the options given below:
A.
C and E only
B.
B and C only
C.
A and B only
D.
D and E only
Correct Answer: B
Explanation:
The correct answer is Option B : B and C only.
Statement A is incorrect. Basophils are actually the least abundant cells of the total white blood cells (WBCs), not the most abundant.
Statement B is correct. Basophils do secrete histamine, serotonin, and heparin. Histamine and serotonin are involved in inflammatory response, while heparin is an anticoagulant.
Statement C is also correct. Basophils are involved in the inflammatory response. They release chemicals such as histamine and serotonin that dilate blood vessels and attract other white blood cells to the site of inflammation.
Statement D is incorrect. Basophils do not have a kidney-shaped nucleus. That description is more appropriate for monocytes, another type of white blood cell.
Statement E is incorrect. Basophils are not agranulocytes. They are granulocytes, a category of white blood cells characterized by the presence of granules in their cytoplasm. Agranulocytes, which lack visible cytoplasmic granules, include lymphocytes and monocytes.
Neutrophils form 60-65 percent of the total WBCs, monocytes form 6-8 percent of the total WBCs and
eosinophils form 2-3 percent of the total WBCs. The total WBCs are approximately 6000-8000 mm–3 of blood.
Thus, the formed elements in the decreasing order of their abundance in blood in humans: -
The atrio-ventricular node (AVN) generates an action potential to stimulate atrial contraction
B.
The tricuspid and the bicuspid valves open due to the pressure exerted by the simultaneous contraction of the atria
C.
Blood moves freely from atrium to the ventricle during joint diastole.
D.
Increased ventricular pressure causes closing of the semilunar valves.
Correct Answer: C
Explanation:
Option (c) is the correct answer because during joint diastole, blood moves freely from atrium to ventricle as atrioventricular valve remain open during joint diastole.
Option (d) is incorrect because decrease in ventricular pressure, during ventricular diastole closes semilunar valves to produce 'dub' heart sound.
Option (a) is incorrect because SA node generates action potential to stimulate atrial contraction.
Option (b) is incorrect because bicuspid and tricuspid valves open due to pressure exerted by blood present in atria and decrease in pressure in ventricles during ventricular diastole.
Persons with 'AB' blood group are called as "Universal recipients". This is due to :
A.
Absence of antibodies, anti-A and anti-B, in plasma
B.
Absence of antigens A and B on the surface of RBCs
C.
Absence of antigens A and B in plasma
D.
Presence of antibodies, anti-A and anti-B, on RBCs
Correct Answer: A
Explanation:
Option (a) is correct because persons with 'AB' blood group contain antigens 'A' and 'B' but lack antibodies anti-A and anti-B in plasma. So, persons with 'AB' blood group can accept blood from persons with AB as well as the other groups of blood due to lack of antibodies in their blood. Therefore, such persons are called "Universal recipients".
Eosinophils are associated with allergic
reactions and release histaminase, Basophils
secrete histamine, serotonin, heparin etc.
and are involved in inflammatory reactions,
Neutrophils are phagocytic cells; Both B and
T lymphocytes are responsible for immune
responses of the body.
The QRS complex represents the
depolarisation of the ventricles, which initiates
the ventricular contraction. The contraction
starts shortly after Q and marks the beginning
of the systole.
What would be the heart rate of a person if the cardiac output is 5L, blood volume in the ventricles at the end
of diastole is 100 mL and at the end of ventricular systole is 50 mL ?
A.
100 beats per minute
B.
125 beats per minute
C.
50 beats per minute
D.
75 beats per minute
Correct Answer: A
Explanation:
Cardiac output = Stroke volume $ \times $ Heart rate
Where stroke volume = End diastolic volume – End systolic volume
= 100 ml – 50 ml
= 50 ml
Match the items given in column I with those in
column II and select the correct option given
below.
Column I
Column II
A. Tricuspid valve
(i) Between left
atrium and left
ventricle
B. Bicuspid valve
(ii) Between right
ventricle and
pulmonary artery
C. Semilunar valve
(iii) Between right
atrium and right
ventricle
A.
A $ \to $ (i), B $ \to $ (ii), C $ \to $ (iii)
B.
A $ \to $ (iii), B $ \to $ (i), C $ \to $ (ii)
C.
A $ \to $ (i), B $ \to $ (iii), C $ \to $ (ii)
D.
A $ \to $ (ii), B $ \to $ (i), C $ \to $ (iii)
Correct Answer: B
Explanation:
The opening between the right atrium and the right ventricle is guarded by a valve formed of three muscular flaps or cusps, the tricuspid valve, whereas a bicuspid or mitral valve guards the opening between the left atrium and the left ventricle.
Adult human RBCs are enucleate. Which of the following statement(s) is/are most appropriate explanation for this feature?
(1) They do not need to reproduce.
(2) They are somatic cells.
(3) They do not metabolise.
(4) All their internal space is available for oxygen transport.
A.
Only (1)
B.
(1), (3) and (4)
C.
(2) and (3)
D.
Only (4)
Correct Answer: D
Explanation:
Red blood cells of adult humans do not have
cell organelles including nucleus, Golgi bodies,
mitochondria, ribosomes, etc. It increases the surface
area of RBCs and enables them to contain more
haemoglobin (the oxygen carrying pigment).
Serum is the fluid that separates from blood
plasma on centrifugation. Serum is essentially similar
in composition to plasma but lacks fibrinogen and other
substances that are used in the coagulation process.
Name the blood cells, whose reduction in number can cause clotting disorder, leading to excessive loss of blood from the body.
A.
Erythrocytes
B.
Leucocytes
C.
Neutrophils
D.
Thrombocytes
Correct Answer: D
Explanation:
Thrombocytes are called blood platelets.
They are minute disc-shaped cell fragments in
mammalian blood. They are formed as fragments of
larger cells found in red bone marrow; they have no
nucleus. They play an important role in blood clotting
and release thromboxane A2
, serotonin and other
chemicals, which cause a chain of events leading to
the formation of a plug at the site of the damage, thus
preventing further blood loss. A reduction in their
number can lead to clotting factors which will lead
to excessive loss of blood from the body.
In mammals, which blood vessel would normally carry largest amount of urea?
A.
Hepatic Vein
B.
Hepatic Portal Vein
C.
Renal Vein
D.
Dorsal Aorta
Correct Answer: A
Explanation:
Hepatic Vein, because the liver produces
urea and other waste materials and then it
pours it all in the right ventricle of the heart
for oxygenation. The heart distributes the
blood to various parts of the body from here.
So the impure blood brought by the Hepatic
Vein and other blood vessels get distributed
through the aorta. This will automatically
imply that the Renal Artery will contain lesser
impure blood than the Hepatic Vein.
Which one of the following animals has two separate circulatory pathways?
A.
Whale
B.
Shark
C.
Frog
D.
Lizard
Correct Answer: A
Explanation:
Whale is a mammal and in mammals, two
separate circulatory pathways are found — systemic
circulation and pulmonary circulation. Oxygenated
and deoxygenated bloods received by the left and right
atria respectively pass on to the left and right
ventricles. Thus, oxygenated and deoxygenated
bloods are not mixed. This is referred to as double
circulation.
iCON Education HYD, 79930 92826, 73309 72826AIPMT 2015 Cancelled Paper
Erythropoiesis starts in
A.
spleen
B.
red bone marrow
C.
kidney
D.
liver
Correct Answer: B
Explanation:
Erythropoiesis is the process of formation
of R.B.C. In the first month of pregnancy,
yolk sac is the haemopoietic tissue. After 5
weeks, it is followed by the liver. Red bone
marrow from 6 months onwards becomes the
principal site of erythropoiesis.
2015
NEET
MCQ
iCON Education HYD, 79930 92826, 73309 72826AIPMT 2015 Cancelled Paper
Blood pressure in the mammalian aorta is maximum during
A.
systole of the left ventricle
B.
diastole of the right atrium
C.
systole of the left atrium
D.
diastole of the right ventricle.
Correct Answer: A
Explanation:
The temporary rise in blood pressure during
the contraction of the heart is called systolic pressure
and the temporary fall in blood pressure during
relaxation of the heart is called diastolic pressure.
Blood pressure is expressed as the ratio of the systolic
pressure over the diastolic pressure. For a healthy
resting adult person, the average systolic/diastolic
pressures are 120/80 mmHg. Aorta is directly supplied
by left ventricle thus, the blood pressure in aorta is
highest during systole of left ventricle. During it, left
ventricle contracts and pushes blood into aorta.
How do parasympathetic neutral signals affect the working of the heart?
A.
Reduce both heart rate and cardiac output.
B.
Heart rate is increased without affecting the cardiac output.
C.
Both heart rate and cardiac output increase.
D.
Heart rate decreases but cardiac output increases.
Correct Answer: A
Explanation:
Control of Heart Beat by Nervous
System: Medulla oblongata has two
regulatory centre:
(i) Accelerator centre - It functions through
sympathetic nervous system (SNS) and
increases heart beat by the secretion of
epinephrine or adrenaline.
(ii) Depressor centre - It functions through
parasympathetic nervous system (PSNS)
by the secretion of acetylcholine. It
decreases heart beat, speed of conduction
of action potential and thereby the
cardiac output.
Person with blood group AB is considered as universal recipient because he has
A.
both A and B antigens on RBC but no antibodies in the plasma
B.
both A and B antibodies in the plasma
C.
no antigen on RBC and no antibody in the plasma
D.
both A and B antigens in the plasma but no antibodies.
Correct Answer: A
Explanation:
Individuals with AB blood group have both
antigen A and B on their RBCs, and no antibodies
for either of the antigen in their plasma. Type O
individuals are without A and B antigens on their
RBCs, but have antibodies for both these antigens in
their plasma. Individuals with blood group AB can
receive blood of A, B or O group, while those with
blood group O can donate blood to anyone.
The figure shows blood circulation in humans with
labels A to D. Select the option which gives correct
identification of label and functions of the part.
A.
A - Artery-Thick walled and blood flows
evenly
B.
C - Vein-Thin walled and blood flows in
jerks/spurts
C.
D - Pulmonary vein-Takes oxygenated
blood to heart, pO2
= 95 mmHg
D.
B - Capillary-Thin without muscle layer and
wall two cell layers thick
Correct Answer: C
Explanation:
A- Artery : Carries blood from heart to
different body parts. It is thick-walled and elastic. The
flow of blood in it is intermittent.
B - Capillary : Nutrients, hormones, gases etc. can
diffuse into tissue cells through capillaries and vice
versa. It is thin-walled, and only one layer thick resting
on basement membrane.
C - Vein : Brings blood from different body parts to
the heart. It is thin-walled and acts as low-resistance
conduct for blood flow.
D - Pulmonary vein : Two pulmonary veins from each
lung transport the oxygenated blood to the left atrium.
Basophils have nucleus which is three-lobed
and have less number of coarse granules. Their
granules take basic stain and release heparin,
histamine and serotonin.
The diagram given here is the standard ECG of a normal person. The P-wave represents the
A.
beginning of the systole
B.
end of systole
C.
contraction of both the atria
D.
initiation of the ventricular contraction.
Correct Answer: C
Explanation:
The P-wave represents the electrical
excitation (or depolarisation) of the atria,
which leads to the contraction of both the
atria. The QRS complex represents the
depolarisation of the ventricles, which
initiates the ventricular contraction. The
contraction starts shortly after Q and marks
the beginning of the systole.
The given figure shows schematic plan of blood
circulation in humans with labels A to D.
Identify the label and give its functions?
A.
A - Pulmonary vein - takes impure blood
from body parts, pO2
= 60 mm Hg
B.
B - Pulmonary artery - takes blood from
heart to lungs, pO2
= 90 mm Hg
C.
C - Vena cava - takes blood from body parts
to right auricle, pCO2
= 45 mm Hg
D.
D - Dorsal aorta - takes blood from heart to
body parts, pO2
= 95 mm Hg
Correct Answer: C
Explanation:
In the given figure: A is pulmonary vein
which brings pure blood from lungs to left atrium, B
is dorsal aorta which carries blood from heart to body
parts, C is vena cava which carries impure blood from
body parts to right auricle, and D is pulmonary artery
which takes impure blood from heart to lungs.
Which one of the following human organs is often called the ''graveyard'' of RBCs?
A.
Gall blader
B.
Kidney
C.
Spleen
D.
Liver
Correct Answer: C
Explanation:
Spleen is an organ of the lymphatic
system located in the left side of the
abdominal cavity under the diaphragm, the
muscular partition between the abdomen and the chest. It is called graveyard of RBC
because fragment of red blood cells, old and
dead cells are constantly being removed from
the blood streams by it.
A certain road accident patient with unknown blood group needs immediate blood transfusion. His one doctor friend at once offers his blood. What was the blood group of the donar?
Given below is the ECG of a normal human. Which one of its components is correctly interpreted below?
A.
Complex QRX - one complete pulse
B.
Peak T - initiation of total cardiac contraction
C.
Peak P and peak R together - systolic and diastolic blood pressures
D.
Peak P- initiation of left atrial contraction only
Correct Answer: A
Explanation:
By counting the number of QRS complexes
that occur in a given time period, one can determine
the heart beat rate (pulse) of an individual. The QRS
complex represents the depolarisation of the
ventricles, which initiates the ventricular contraction.
Which one of the following plasma proteins is involved in the coagulation of blood?
A.
Albumin
B.
Serum amylase
C.
Globulin
D.
Fibrinogen
Correct Answer: D
Explanation:
Blood plasma is a faint yellow, slightly
alkaline and somewhat viscous fluid. The plasma
contains a number of proteins: serum albumin, serum
globulins, properdin, prothrombin and fibrinogen.
Prothrombin and fibrinogen play a role in blood clotting.
A person with unknown blood group under ABO system, has suffered much blood loss in an accident and needs immediate blood transfusion. His friend who has valid certificate of his own blood type, offers for blood donation without delay. What would have been the type of blood group of the donar friend?
A.
Type B
B.
Type AB
C.
Type O
D.
Type A
Correct Answer: C
Explanation:
The ABO blood system classifies human blood into four types based on the presence or absence of certain antigens on the surface of red blood cells. These types are A, B, AB, and O. For a safe blood transfusion, it's crucial that the donor's blood type is compatible with the recipient's. Compatibility is determined by antigens on the red blood cells and antibodies in the plasma. Here's how the compatibility works:
Type A: Has A antigens on the red blood cells and anti-B antibodies in the plasma.
Type B: Has B antigens on the red blood cells and anti-A antibodies in the plasma.
Type AB: Has both A and B antigens on the red blood cells but does not have anti-A or anti-B antibodies in the plasma. People with AB blood are universal recipients for ABO transfusions because they do not have anti-A or anti-B antibodies.
Type O: Has no antigens on the red blood cells but has both anti-A and anti-B antibodies in the plasma. People with O blood are universal donors for ABO transfusions because they have no A or B antigens on their red blood cells.
Given the scenario where the recipient's blood type is unknown, the safest option for blood transfusion would be Type O blood. This is because Type O blood has no A or B antigens on the red blood cells, making it compatible with any recipient regardless of their ABO blood type. Thus, regardless of the recipient's unknown ABO blood group, a friend with Type O blood could donate without causing a harmful reaction due to ABO incompatibility.
Fastest distribution of some injectible material/medicine and with no risk of any kind can be achieved by injecting it into the
A.
muscles
B.
arteries
C.
veins
D.
lymph vessels.
Correct Answer: C
Explanation:
The fastest distribution of an injectable material or medicine, with minimal risk, is achieved by injecting it into the veins, making Option C the correct answer. Here’s why:
Veins: When medicine is injected into the venous system (intravenously), it is quickly carried throughout the body by the bloodstream. The advantage of venous injection (IV injection) is the rapid onset of effects as the medicine is directly entered into the circulatory system, bypassing the need for absorption. This method also allows for precise control over the dosage and is used for substances that might be irritants or not effective if administered by other routes.
Arteries: Injecting a substance directly into an artery is far more dangerous and is rarely done outside of specialized medical procedures. The arterial system is under much higher pressure than the venous system, which increases the risk of complications, including arterial damage and the potential for creating embolisms that could cause strokes or other serious issues.
Muscles: Intramuscular injections are absorbed more slowly than intravenous injections because the blood flow to muscle tissues is less than to veins. This method is used for certain types of medication that need to be absorbed over a longer period. It's safer than arterial injection but slower in effect compared to venous injection.
Lymph Vessels: The lymphatic system is not designed for the fast distribution of substances throughout the body. It has a much slower flow than the circulatory system and is involved in managing the immune response and transporting waste and other materials out of the bodily tissues. Injection into the lymphatic system is not a common practice for administering medications for systemic effect.
In summary, intravenous injection (Option C) is the preferred route for the immediate and safest distribution of injectable substances throughout the body.
Given below are four statements (i-iv) regarding human blood circulatory system.
(i) Arteries are thick-walled and have narrow lumen as compared to veins.
(ii) Angina is acute chest pain when the blood circulation to the brain is reduced.
(iii) Persons with blood group AB can donate blood to any person with any blood group under ABO system.
(iv) Calcium ions play a very important role in blood clotting.
Which two of the above statements are correct?
A.
(i) and (iv)
B.
(i) and (ii)
C.
(ii) and (iii)
D.
(iii) and (iv)
Correct Answer: A
Explanation:
The term angina means chest pain. In this
disease enough oxygen does not reach the heart
muscles. The patient experiences heart pain usually
in front of the chest.
AB blood group person have both antigens A and B,
but do not have antibodies in the plasma. Due to the
presence of both the antigens, AB blood group person
cannot donate blood to anyone. However, the person
can receive blood from any blood group as it has no
antibodies. Thus, AB blood group is a universal
recepient.
The haemoglobin content per 100 ml of blood of a normal healthy human adult is
A.
5 - 11 mg
B.
25 - 30 mg
C.
17 - 20 mg
D.
12 - 16 mg.
Correct Answer: D
Explanation:
The haemoglobin content per 100 ml of blood in a normal healthy human adult is actually found in the range of 12 - 16 grams. Therefore, the correct answer is Option D: 12 - 16 mg. However, it's important to note that there seems to be a mistake in the unit provided in the options. The correct unit should be grams (g) and not milligrams (mg), as haemoglobin content in blood is measured in grams per deciliter (g/dL). So, the correct expression reflecting normal haemoglobin levels should be 12 - 16 g/dL, not mg.
In general, average ranges for haemoglobin levels vary by age and sex, typically:
For men: 13.8 to 17.2 grams per deciliter
For women: 12.1 to 15.1 grams per deciliter
These levels can be affected by various factors including diet, physical activity, and medical conditions. It's essential for individuals to have their haemoglobin levels within the normal range as it's crucial for effectively transporting oxygen throughout the body. Deviations from the normal range can indicate different medical conditions that may require further investigation.
