Tag: blood in humans

Questions Related to blood in humans

Consider the following statements (A - C) each with one or two blanks.
(A)(1) are the most abundant cells (60-65 per cent) of the total WBCs and (2) are the least (0.5-1 per cent) among them.
(B)Platelets are cell fragments produced from (3).
(C)During clot formation, fibrins are formed by the conversion of inactive (4) in the plasma by the enzyme (5).
Which one of the following options, gives the correct fill ups for the respective blank numbers from (1) to (5) in the statements?

evs transportation in animal and plants blood in humans circulatory system - blood basics of blood and heart

  1. (l)-Neutrophils, (2)-basophiIs, (4)-fibrinogens, (5)-thrombin

  2. (3)-mast cells, (4)-throm bo kinase, (5)prothrombin

  3. (3)-megakaryocytes, (4) prothrombin, (5)thrombin

  4. (1)-Basophils, (2)-neutrophils, (3)-reticulocytes

Show answer
Correct Option: A
Explanation:

Out of all other leucocytes, the neutrophils (60-65%) are most abundant and the least are basophils (0.5-1%). Platelets are cell fragments produced from megakaryocytes. During the blood clotting, the enzyme thrombin converts inactive fibrinogens into active fibrins.. 

Thus, the correct answer is '(l)-Neutrophils, (2)-basophiIs, (4)-fibrinogens, (5)-thrombin).'

One haemoglobin carries how many molecules of $O _{2}$? 

evs transportation in living organisms blood in humans circulatory system - blood basics of blood and heart

  1. 4

  2. 2

  3. 6

  4. 8

Show answer
Correct Option: A
Explanation:

Hb contains a protein portion called globin and a pigment portion called haem. The haem portion consists of four atoms of iron, each capable of combining with a molecule of $O _{2}$. Thus, one Hb carries 4 molecules of $O _{2}$.

Which of the following statements is true about RBCs in humans?

evs transportation in living organisms blood in humans circulatory system - blood basics of blood and heart

  1. They carry about 20-25 per cent of $CO _{2}$.

  2. They transport 99.5 per cent of $O _{2}$.

  3. They transport about 80 per cent oxygen only and the rest 20 per cent of it is transported in dissolved state in blood-plasma.

  4. They do not carry $CO _{2}$ at all.

Show answer
Correct Option: A
Explanation:

Nearly 20-25% of $CO _{2}$ is transported by RBCs whereas 70% of it is carried as bicarbonate in plasma. About 7% of $CO _{2}$ is carried in a dissolved state through plasma. About 97% of $O _{2}$ is carried by RBCs in the blood. About 3% of $O _{2}$ Is transported in a dissolved state through the plasma.

So, the correct answer is 'They carry about 20-25 per cent of 
CO2CO2'

............. in plant cell and ........................ in mannalian cells are non-nucleated in mature stages.

biology transportation in animal and plants blood in humans circulatory system - blood basics of blood and heart

  1. Tracheids, osteocytes

  2. Sieve tubes, RBC

  3. Companion cells, RBC

  4. Parenchyma, bone marrow

Show answer
Correct Option: B
Explanation:

The sieve tubes are supporting cells in the conducting tissue of the plant and are characterised by the absence of a nucleus. 

The RBC in the blood does not have a nucleus so as to carry enough oxygen.
So, the correct option is 'Sieve tubes, RBC'.

Platelets have no nucleus and genetic material.

biology transportation in animal and plants blood in humans circulatory system - blood basics of blood and heart

  1. True

  2. False

Show answer
Correct Option: A
Explanation:
Platelets are produced by budding off from a giant multinucleated marrow cell called a megakaryocyte. They are just fragments of larger cells so they do not have the nucleus and genetic material.
So, the correct answer is 'True.

Which of the following cells do not take part in transportation?

biology transportation in animal and plants blood in humans circulatory system - blood basics of blood and heart

  1. RBC

  2. WBC

  3. Platelets

  4. Both B and C

Show answer
Correct Option: D
Explanation:

Hemoglobin (Hb or Hgb ) is an iron-containing protein present in Erythrocytes or Red blood cells (RBC) of almost all vertebrates. Each hemoglobin is made up of 4 subunits, 2 alpha subunits, and 2 beta subunits. Each subunit surrounds the central heme group that contains iron and binds to one oxygen molecule. It carries oxygen from lungs to tissues. It also helps in the transportation of carbon dioxide, hydrogen ions back to the lungs from the tissues. Hence RBC helps in transportation of gases while WBC takes parts in immune function and protects the body from infectious diseases and foreign invaders(bacteria, viruses other pathogens) and platelets in blood coagulation.

So, the correct answer is 'Both B and C'.

Which of the following cells gets activated during bleeding?

evs transportation in animal and plants blood in humans circulatory system - blood basics of blood and heart

  1. RBC

  2. WBC

  3. Platelets

  4. None of the above

Show answer
Correct Option: C
Explanation:
If one of your blood vessels gets damaged(bleeding), it sends out signals to the platelets. The platelets then rush to the site of damage. they form a plug (clot) to fix the damage. The process of spreading across the surface of a damaged blood vessel to stop bleeding is called adhesion. This is because when platelets get to the site of the injury, they grow sticky tentacles that help them stick (adhere) to one another. They also send out chemical signals to attract more platelets. The additional platelets pile onto the clot in a process called aggregation.

So, the correct answer is 'Platelets'.

Platelets helps in 

evs transportation in animal and plants blood in humans circulatory system - blood basics of blood and heart

  1. Transport of gases

  2. Clotting

  3. Fight against disease

  4. None of the above

Show answer
Correct Option: B
Explanation:
When an injury or a trauma occurs platelets are exposed to air this phenomenon stimulates the platelets to start the clotting process. These platelets react with the protein called fibrinogen with the help of vitamin k and calcium. Fibrinogen forms a mesh of tiny threads that collects red blood cells, which plug the open blood vessels as it dries. This is called a clot. Hence platelets help in clotting.
So, the correct answer is 'Clotting'.

Loss of haemoglobin can be controlled by

evs transportation in animal and plants blood in humans circulatory system - blood basics of blood and heart

  1. Platelets

  2. RBC

  3. WBC

  4. None of the above

Show answer
Correct Option: A
Explanation:

Platelets are cell fragments produced from megakaryocytes (special cells in the bone marrow). They are also called as thrombocytes. An injury or a trauma stimulates the platelets in the blood to release certain factors which activate the mechanism of coagulation or blood clotting. They also change their shape from round to spiny and stick to the broken vessel wall and each other and forms net-like structure during bleeding. This prevents the loss of hemoglobin through bleeding.

So, the correct answer is 'Platelets'.

Critical count of Platelete is _______________

evs transportation in living organisms blood in humans circulatory system - blood basics of blood and heart

  1. $4\times 10^4 /mm^3$

  2. $1 \ lakh /mm^3$

  3. $2 \  lakh /mm^3$

  4. $4 \  lakh /mm^3$

Show answer
Correct Option: B
Explanation:
Platelet count is the number of platelets in the blood. The normal platelet count ranges from 2- 5 lakh cells/mm$^3$. In disease conditions like dengue, the platelet count is decreased below the average value. This condition is called thrombocytopenia. If platelet count drops below 1 lakh /mm$^3$, it is considered as critical platelet count it denotes that person is at high risk of bleeding.
So, the correct answer is 'Option B'.