Tag: circulatory system and organs

Questions Related to circulatory system and organs

The portion of heart which doesn't receive proper blood supply becomes

  1. Strong

  2. Dead

  3. Weak

  4. Diseased


Correct Option: C
Explanation:
When the heart tissue does not receive an adequate blood supply, it cannot function. The heart muscle weakened due to lack of food and oxygen. Improper supply of blood to heart usually causes pain and infected portion of muscles may die.
So the correct answer is 'Weak'.

Read the following statements carefully.
$(1)$ In fishes the heart pumps out deoxygenated blood which is oxygenated by the gills and supplied to the body parts from where deoxygenated blood is returned to the heart
$(2)$ The openings of the right and the left ventricles into the pulmonary artery and the aorta respectively are provided with the mitral valves.
$(3)$ The nodal musculature has the ability to generate action potential without any external stimuli, i.e., it is auto-excitable
$(4)$ The T-wave of ECG represents depolarization of the ventricles
Which of the given two statements are correct?

  1. $1$ and $3$

  2. $2$ & $4$

  3. $1$ and $2$

  4. $3$ & $4$


Correct Option: A
Explanation:

The correction in statements (2) and (4) are:

  • In vertebrates, the mitral valves are present between the left atrium and the left ventricle.
  • The T wave of ECG represents repolarization of the ventricles, not depolarization.
So, the correct answer is '1 and 3'.

Why it is necessary to separate oxygenated and deoxygenated blood in mammals and birds?

  1. To stop mixing of oxygenated and deoxygenated blood

  2. To maintain body temperature

  3. To suffice higher energy need

  4. All of the above


Correct Option: D
Explanation:

The heart of the higher organism is well equipped with the vascular system. the arteries carry the oxygenated blood while the veins carry the deoxygenated blood. This prevents the mixing of oxygenated and deoxygenated blood.

So, the correct answer is option A.

The upper chambers of the heart are called

  1. Auricles

  2. Ventricles

  3. Spiracles

  4. Tentacles


Correct Option: A
Explanation:

A normal heart has two upper and two lower chambers. The upper chambers, the right, and left atria, receive incoming blood. The lower chambers, the more muscular right, and left ventricles pump blood out of your heart.

So, the correct option is 'Auricles'.

When the muscles of the heart relax

  1. Blood flows from lungs into the left auricle

  2. Blood is pumped into the right auricle from all over the body

  3. Both a and b

  4. Blood flows from the left ventricle to the rest of the body


Correct Option: C
Explanation:

When the muscles of the heart relax, the right atrium receives deoxygenated blood from all parts of the body through superior, inferior vena cava and coronary sinus. The left atrium receives oxygenated blood from the lungs through two pairs of pulmonary veins. Thus option C is the correct answer. 

When the muscles of the heart contract?

  1. Blood is pumped from the right ventricle into the lungs.

  2. Blood flows from the lungs into the left auricle.

  3. Blood is pumped into the right auricle from all over the body.

  4. None of the above.


Correct Option: A
Explanation:

During ventricular systole, the deoxygenated blood from the right ventricle enters the pulmonary trunk, which carries blood to lungs for oxygenation. Thus option A is the correct answer. 

Which of the following statements is false?

  1. Oxygenated blood is pumped to all other parts of the body from left ventricle.

  2. Gaseous exchange in the alveoli happens through capillaries.

  3. Blood-from the right side of the heart enters into left side through right auricle and left auricle.

  4. Lungs oxygenate the deoxygenated blood.


Correct Option: C
Explanation:

The pulmonary artery arises from the right ventricle and carries deoxygenated blood to lungs for oxygenation. Lungs oxygenate the deoxygenated blood. This oxygenated blood is pumped to all parts of the body. Thus option C is the correct answer. 

The lower chambers of the heart are called

  1. Auricles

  2. Ventricles

  3. Spiracles

  4. Tentacles


Correct Option: B
Explanation:

The upper chambers are called the left and right atria, and the lower chambers are called the left and right ventricles. A wall of muscle called the septum separates the left and right atria and the left and right ventricles. The left ventricle is the largest and strongest chamber in your heart.

So, the correct option is 'Ventricles'.

.......... pumps deoxygenated blood to the lungs.

  1. Right auricle

  2. Right ventricle

  3. Left auricle

  4. Left ventricle


Correct Option: B
Explanation:

During ventricular systole, the deoxygenated blood from the right ventricle enters the pulmonary trunk, which carries blood to lungs for oxygenation. Thus option B is the correct answer. 

Blood from the left ventricle is pumped to

  1. Lungs

  2. Left auricle

  3. Right ventricle

  4. All parts of the body


Correct Option: D
Explanation:

The left ventricle is the thickest of the heart's chambers and is responsible for pumping oxygenated blood to tissues all over the body. By contrast, the right ventricle solely pumps blood to the lungs.

So, the correct option is 'All parts of the body'.