Tag: biology

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Questions Related to biology

Multiple choice biology transportation in plants and circulation in animals heart beat cardiac cycle heart, blood vessels and cardiac cycle

The second heart sound (dubb) is associated with the closure of

  1. Tricuspid valve

  2. Semilunar valves

  3. Bicuspid valve

  4. Tricuspid and bicuspid valves
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation
The closing of different valves in the heart produces different characteristic sound commonly known as the lub-dub sounds. The lub sound is the first sound of the heart. The dub sound is the second sound of the heart that is produced by the closing of the semilunar valves in the heart.
Thus, the correct answer is 'Semilunar valves.'
Multiple choice biology transportation in plants and circulation in animals heart beat cardiac cycle heart, blood vessels and cardiac cycle

If the systolic pressure is $120$mm Hg and diastolic pressure is $80$mm Hg, the pulse pressure is $80$mm Hg, the pulse pressure is ______.

  1. $120\times80 = 9600$mm Hg
  2. $120+80 = 200$ mm Hg
  3. $120 - 80 = 40$mm Hg
  4. $\frac{120}{40} = 3$mm Hg
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation
The pulse pressure can be defined as the difference between the diastolic and systolic pressure of an individual’s heart. If the normal diastolic and systolic pressure of the adult human heart is 120 mm Hg and 80 mm Hg, respectively then the pulse pressure is 120 - 80 = 40 mm Hg.
Thus, the correct answer is '120−80=40mm Hg.'
Multiple choice biology transportation in plants and circulation in animals heart beat cardiac cycle heart, blood vessels and cardiac cycle

An adult human with average health has systolic and diastolic pressures as

  1. 120 mm Hg and 80 mm Hg

  2. 50 mm Hg and 80 mm Hg

  3. 80 mm Hg and 80 mm Hg

  4. 70 m Hg and 120 mm Hg
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

Blood pressure is the pressure against the walls of the blood vessels produced by the discharge of blood into them by contraction of the left ventricle.

Systolic pressure: The temporary rise in BP during the contraction of the heart is called systolic pressure.
Diastolic pressure: The temporary fall in BP during the relaxation of the heart is termed as diastolic pressure.
For a healthy resting adult person, the average systolic/ diastolic pressures are 120/80 mm Hg in arteries near the heart.
So, the correct answer is '120 mm Hg and 80 mm Hg'.

Multiple choice biology transportation in plants and circulation in animals heart beat cardiac cycle heart, blood vessels and cardiac cycle

Which one of the following is a matching pair?

  1. Lubb - sharp closure of AV valves at the beginning of ventricular systole

  2. Dub - sudden opening of semilunar valves at the beginning of ventricular diastole

  3. Pulsation of the radial artery - valves in the blood vessels

  4. Initiation of the heart beat - Purkinje fibres
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

The first heart sound (Lubb) is caused by the closure of the atrioventricular valves at the start of ventricular systole.

Multiple choice biology transportation in plants and circulation in animals heart beat cardiac cycle heart, blood vessels and cardiac cycle

The first heart sound is produced when

  1. Intraventricular pressure decreases

  2. Semilunar valve snaps shut

  3. Bicuspid and tricuspid close quickly

  4. Diastole begins
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

first heart sound is produced by the closing of the atrioventricular valves . The first heart sound, or S1, forms the "lub" of "lub-dub" and is composed of components M1 (mitral valve closure) and T1 (tricuspid valve closure). Normally M1 precedes T1 slightly. It is caused by the closure of the atrioventricular valves, i.e. tricuspid and mitral (bicuspid), at the beginning of ventricular contraction, or systole. So, the correct option is C.( Bicuspid and tricuspid close quickly )

Multiple choice biology simple nutrients into cells heart beat cardiac cycle heart, blood vessels and cardiac cycle

In a normal human adult (at resting position), how much blood does the heart pump per minute?

  1. 5 litre

  2. 3 litre

  3. 1 litre

  4. 7 litre
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

The blood travels around the body and back to the heart in about one minute if the person is at rest. The heart beats 70 times a minute, with each beat the heart pumps 60 to 90 mililiters (2 to 3 ounces) of blood out of the heart. It can move 5 liters of blood in one minute and 7600 liters (2000 gallons) per day. So, the correct option is "A" (5 Litre).

Multiple choice biology transportation in plants and circulation in animals heart beat cardiac cycle heart, blood vessels and cardiac cycle

Which of the following statements is false?

  1. $Mg^{2+}$ ions form a complex with ATP
  2. $Ca^{2+}$ ions are important in blood clotting
  3. $Ca^{2+}$ ions are not important in maintaining the regular beating of the heart
  4. $Mg^{2+}$ ions are important in the green parts of plants.
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

Calcium is important for heart because the movement of calcium ions help the heart muscles to contract. This occurs because: calmodulin, a protein binds to the sodium channel, helps keep it open. Calcium ions regulate the connection between the protein and the channel by causing the protein to hook up to the channel. This in turn, keeps it open and allows sodium ions to pass through. In the absence of Ca$^2$$^+$ the heart beat will be irregular. 

So the correct answer is ' Ca2+ ions are not important in maintaining the regular beating of the heart'.

Multiple choice biology transportation in plants and circulation in animals heart beat cardiac cycle heart, blood vessels and cardiac cycle

The first heart sound is

  1. DUP

  2. LUBB

  3. LUPP

  4. BUD
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

The first heart sound 'lubb' is made by the closing of the mitral valve and tricuspid valve (atrioventricular valves). The second heart sound is 'dub' and is caused by the closure of the aortic valve and the pulmonary valve. 

So, the correct option is 'LUBB'.