Tag: biology

Quizzes (1160) Questions (12174)

Questions Related to biology

Multiple choice management of water uses and limitations of dams air, water and soil management of natural resources biology

Making of small check dams across the flooded gullies is important because they

  1. hold water and prevent soil erosion

  2. recharge ground water

  3. help stagnate water

  4. hold water for irrigational purpose
Reveal answer Fill a bubble to check yourself
A,C Correct answer
Explanation

Check dams are small barriers built across gullies to slow down water flow, which helps in retaining water, reducing soil erosion, and facilitating groundwater recharge.

Multiple choice management of water uses and limitations of dams air, water and soil management of natural resources biology

In our country, there are attempts to increase the height of several existing dams like Tehri and Almati, dams across Narmada. Choose the correct statements among the following that are a consequence of raising the height of dams.

  1. Terrestrial flora and fauna of the area is destroyed completely

  2. Dislocation of people and domestic animals living in the area

  3. Valuable agricultural land may be permanently lost

  4. It will generate permanent employment for people
Reveal answer Fill a bubble to check yourself
A,B,C Correct answer
Explanation

Raising dam heights increases the reservoir area, which leads to the submergence of land, resulting in the loss of flora, fauna, agricultural land, and the displacement of human and animal populations.

Multiple choice management of water uses and limitations of dams air, water and soil management of natural resources biology

The problems for criticism about large dams are that they

  1. displace large number of peasants and triables without proper rehabilitation

  2. swallow up huge amounts of public money withrout the generation of proportionate benefits

  3. contribute enormously to deforestation and the loss of biological diversity

  4. all of the above
Reveal answer Fill a bubble to check yourself
D Correct answer
Multiple choice cardiac cycle simple nutrients into cells the circulatory system biology

Pacemaker is situated in the

  1. Wall of right atrium

  2. Interauricular septum

  3. Interventricular septum

  4. Wall of left atrium
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation
The actual structure that serves as the heart's primary pacemaker is called the sinoatrial node (SA node). The SA node is a little bundle of cells located in the wall of the right atrium, the small upper chamber on the right side of the heart.
Thus, the correct answer is 'Wall of right atrium.'

Multiple choice cardiac cycle simple nutrients into cells the circulatory system biology

The pacemaker of heart is

  1. Foramen ovale

  2. Sinoatrial node

  3. Ductus arteriosus

  4. Bundle of His

  5. Vagus nerve
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

Electrical impulses from the heart muscle cause your heart to beat (contract). This electrical signal begins in the sinoatrial (SA) node, located at the top of the heart's upper-right chamber (the right atrium). The SA node is sometimes called the heart's“natural pacemaker.”

So, the correct option is 'Sino-atrial node'.

Multiple choice cardiac cycle simple nutrients into cells the circulatory system biology

The heart beat is initiated and regulated by nodal tissue made of specialised cardiac muscles called

  1. Spongy tissue

  2. Purkinje tissue

  3. Alveolar tissue

  4. None of these
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

Purkinje tissue is influenced by electrical discharge from the sinoatrial node. During the ventricular contraction portion of the cardiac cycle, the Purkinje fibres carry the contraction impulse from both the left and right bundle branch to the myocardium of the ventricles. In this way these fibres control and initiate heart beat.

So, the correct option is B. ( Purkinje tissue )

Multiple choice cardiac cycle simple nutrients into cells the circulatory system biology

The action potential is conducted from the atria to ventricles by:

  1. Purkinje fibre

  2. SA node and AVN

  3. Bundle of his and SAN

  4. All of the above
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation
  • Sino-atrial node (SA node) is located the right upper corner of the right atrium and AVN(AV node) is located in the lower-left corner of the right atrium close to the atrioventricular septum.
  • The SAN can generate the maximum number of action potentials, i.e., $70-75 min^{–1}$, and is responsible for initiating and maintaining the rhythmic contractile activity of the heart. Therefore, it is called the pacemaker. From the SA node, the action potential is conducted from the atria to ventricles by AVN.
  • Hence the action potential is conducted from the atria to ventricles via SA node and AVN.
  • So, the correct answer is 'SA node and AVN'.
Multiple choice cardiac cycle simple nutrients into cells the circulatory system biology

Sinoatrial node (SAN) is located at

  1. Right upper corner of right atrium

  2. Right Lower lower corner of right atrium

  3. Right upper corner of left atrium

  4. Left upper corner of right atrium
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

The sinoatrial node is present at the right upper corner of the right atrium. The node is present below the Vena Cava. It initiates the autonomous contraction of the heart muscles.

So, the correct option is 'Right upper corner of right atrium'.

Multiple choice cardiac cycle simple nutrients into cells the circulatory system biology
Give these structure of the conduction system of the heart :
1. It is Atrioventricular bundle
2. AV node
3. Bundle branches
4. Purkinje fibres 
 5. SA node
Choose the arrangement that lists the structures in an order of an action potential passes through them.
  1. $2,5,3,1,4$
  2. $5,2,1,3,4$
  3. $2,5,1,3,4$
  4. $5,2,4,1,3$
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

The correct series is 

5.SA node
2.AV node
1.It is atrioventricular bundle
3.Bundle branches
4. Purkinje fibers
So, the correct answer is '5,2,1,3,4'