Railway Science (Biology – Circulatory System) (Part-II)

Total Questions: 19

11. Choose the option that is NOT true about the vascular system. [RRB Group D 05/10/2018 (Morning)]

Correct Answer: (d) Life span of human RBCs is 15-20 days.
Solution:

The life span of human RBCs is 115-120 days. Vascular system - Also called the circulatory system, is made up of the vessels that carry blood and lymph through the body. It is responsible for transporting blood, nutrients, gases, and hormones to and from the cells throughout the body.
The average adult has about 60,000 miles of blood vessels. Red blood cells are the most abundant cells in the blood. White blood cells are responsible for fighting infection. Platelets help to stop bleeding by forming clots.

12. Heart muscles are _____ . [RRB Group D 05/10/2018 (Afternoon)]

Correct Answer: (b) Cylindrical, branched and single-nuclei
Solution:

Many cardiac muscle cells assemble in a branching pattern to form a cardiac muscle. Based on appearance, cardiac muscles are striated. They are involuntary in nature as the nervous system does not control their activities directly.

13. Which of the following options is not correct about red blood cells? [RRB Group D 09/10/2018 (Afternoon)]

Correct Answer: (c) Length – 5.7 ΞΌπ‘š
Solution:

Red blood cells, or erythrocytes, are specialized cells primarily responsible for transporting oxygen from the lungs to the tissues and removing carbon dioxide from the tissues to the lungs. The average diameter of a red blood cell is about 7.5 ΞΌm.

14. Which of the following options is NOT true of RBCs ? [RRB Group D 09/10/2018 (Evening)]

Correct Answer: (a) Shape - Amoeboid or circular
Solution:

The shape of RBCs is a biconcave disk. Red blood cells (RBC) which contain a red pigment called haemoglobin. Haemoglobin binds with oxygen and transports it to all the parts of the body and ultimately to all the cells.
Blood is the fluid which flows in blood vessels. It transports substances like digested food from the small intestine to the other parts of the body. It carries oxygen from the lungs to the cells of the body.

15. Which of the following is called the 'soldier' of the human body? [RRB Group D 10/10/2018 (Morning)]

Correct Answer: (a) WBCs
Solution:

WBCs (White blood cells) - A type of blood cell that is made in the bone marrow and found in the blood and lymph tissue. White blood cells are part of the body’s immune system.
They help the body fight infection and other diseases. Types of white blood cells - Granulocytes (neutrophils, eosinophils, and basophils), Monocytes, and Lymphocytes (T cells and B cells).

16. Fibers are absent in: [RRB Group D 16/10/2018 (Evening)]

Correct Answer: (b) Blood
Solution:

Blood is a specialized connective tissue. It contains red blood cells, white blood cells, platelets, and plasma, none of which have a fibrous structure. The quantity of blood in the human’s body is 7% of the total weight.

17. The walls of the ventricles are______ than atrial walls. [RRB Group D 31/10/2018 (Afternoon)]

Correct Answer: (d) thicker
Solution:

Ventricles have thicker walls than auricles because they have to pump blood to different organs and the pressure with which the blood flows through them is more than the auricles. Human heart has four chambers, two relatively small upper chambers called atria and two larger lower chambers called ventricles.

18. Which component of the blood transports food, COβ‚‚ and nitrogenous waste [RRB ALP Tier - I (14/08/2018) Morning]

Correct Answer: (d) Plasma
Solution:

It transfers dissolved substances such as nutrients and electrolytes etc. It also carries blood components throughout the body.

19. …….. is the liquid part of the blood of which 92% is water and the remaining 8% is proteins, minerals, hormones, enzymes, and so on. [RRB ALP Tier - I (31/08/2018) Afternoon]

Correct Answer: (b) Plasma
Solution:

It is the liquid portion of blood. About 55% of our blood is plasma, and the remaining 45% are red blood cells, white blood cells and platelets that are suspended in the plasma.
Red blood cell (RBC) (Erythrocyte) is a type of blood cell that is made in the bone marrow and found in the blood. It contains a protein called hemoglobin, which carries oxygen from the lungs to all parts of the body.
White blood cells (WBC)(Leukocyte) are part of the body's immune system. It helps the body to fight infection and other diseases.
Platelets (Thrombocytes) are pieces of very large cells in the bone marrow called megakaryocytes. They help form blood clots to slow or stop bleeding and to help wounds heal.