HEART AND CIRCULATORY SYSTEM (Part-I)

(d) AV node

Total Questions: 32

11. Who discovered blood circulation? [S.S.C. Online C.H.S.L. (T-I) 5.08.2021 (Shift-II) S.S.C. Online MTS (T-I) 5.01.2017 (Shift-III)]

Correct Answer: (c) William Harvey
Note:

William Harvey was the first person to describe the circulation of blood in the body. He showed that arteries and veins form a complete circuit. The circuit starts at the heart and leads back to the heart. The heart's regular contractions drive the flow of blood throughout the whole body.

12. Blood group was discovered by [S.S.C. Online Graduate Level (T-I) 6.09.2016 (Shift-II) S.S.C. Online MTS (T-I) 4.01.2017 (Shift-I)]

Correct Answer: (c) Landsteiner
Note:

Based on the antigens present in the cytoplasm of red blood cells, Landsteiner discovered the blood groups in the year 1900 and divided it into four categories (A, B, AB, O). Landsteiner found that the presence of antigen-protein substances called the plasma of blood contains protein substances related to the synthesis of food. Such substances present in the serum of red cells are called antigens and the substances present in plasma are called antibodies. The Rh antigen was discovered by Landsteiner and Wiener in the year 1940. Penicillin was discovered by Alexander Fleming. The blood circulatory system was discovered by William Harvey.

13. In 1930, which scientist was awarded the Nobel Prize for describing the human ABO blood group system? [S.S.C. Online CHSL (T-I) 13.01.2020 (Shift-I)]

Correct Answer: (a) Karl Landsteiner
Note:

In 1930, Landsteiner was awarded the Nobel Prize for his description of the human ABO blood group system, which he himself considered an accidental discovery. Karl Landsteiner discovered human blood groups in 1900 and laid the foundation for the modern medical practice of blood transfusion.

14. Blood group AB has— [S.S.C. Online Graduate Level (T-I) 10.09.2016 (Shift-II)]

Correct Answer: (b) No antibody
Note:

White blood cells protect the body against infection. As your immune system recognizes the difference between your own blood and the invading cells, it produces antibodies to block and remove foreign cells.

15. What is the main purpose of leukocytes? [S.S.C. Online Graduate Level (T-I) 1.09.2016 (Shift-III)]

Correct Answer: (d) to carry immune response
Note:

White blood cells protect your body against infection. As your white blood cells travel through your bloodstream and tissues, they locate the site of infection and act as an army geared to notify other white blood cells of their location to help defend your body from an attack of an unknown organism. Once your white blood cells find the infection, they invade the producing antibody proteins to attack the organisms and destroy it.

16. Which cells in our body are popularly called "soldiers of the human body"? [S.S.C. Online Graduate Level (T-I) 4.06.2019 (Shift-II)]

Correct Answer: (a) White Blood Cells
Note:

The white blood cells are called the soldiers of the body because they are responsible for protecting our bodies from infective pathogens and parasites.

17. Which component of blood fights against germs that enter the human body? [S.S.C. Online MTS (T-I) 9.08.2019 (Shift-II)]

Correct Answer: (d) White blood cells
Note:

The white blood cells are called the soldiers of the body because they are responsible for protecting our bodies from infective pathogens and parasites.

18. ‘Leukopenia’ is an abnormal— [S.S.C. Online CHSL (T-I) 16.01.2020 (Shift-III)]

Correct Answer: (b) decrease in white blood cells
Note:

Leukopenia is a condition of the human body’s immune system in which there is a lack of white blood cells in the person’s blood. This increases the risk of various external infections in the person. Human blood contains different types of blood cells, including white blood cells, also known as leukocytes that help fight infection.

19. Lymph, a light clear fluid made up of white blood cells, attacks harmful _______ in the blood. [S.S.C. Online CGL (T-I) 13.08.2021 (Shift-II)]

Correct Answer: (a) Bacteria
Note:

Lymph is a light clear fluid found in the body, which is made up of white blood cells. It works by destroying the harmful bacteria that reach the blood.

20. The largest artery in the human body is [S.S.C. Online Graduate Level (T-1) 2.09.2016 (Shift-1)]

Correct Answer: (a) Aorta
Note:

The largest artery is the aorta, the main high-pressure pipeline connected to the heart's left ventricle. The aorta branches into a network of smaller arteries that extend throughout the body. The arteries' smaller branches are called arterioles and capillaries. The pulmonary arteries carry oxygen-poor blood from the heart to the lungs under low pressure, making these arteries unique.