Tag: biology

Questions Related to biology

Consider the following statements regarding blood pressure.
1. It is the pressure exerted by the blood on the walls of any blood vessel.
2. It decreases in the arteries as the distance from the heart increases.
3. It is lower in the capillaries than in the arteries.
4. It is usually lower in women than in men.

biology human body and organ system blood pressure circulatory system transportation in animal and plants

  1. 1 and 4 are correct.

  2. 2, 3 and 4 are correct.

  3. 1 and 3 are correct.

  4. 1, 2, 3 and 4 are correct.

Show answer
Correct Option: D
Explanation:

Blood pressure (BP) is the pressure exerted by circulating blood upon the walls of blood vessels. It is usually measured at a person's upper arm. Blood pressure is usually expressed in terms of the systolic (maximum) pressure over diastolic (minimum) pressure and is measured in millimeters of mercury (mm Hg). It is one of the vital signs along with respiratory rate, heart rate, oxygen saturation, and body temperature. Normal resting blood pressure in an adult is approximately 120/80 mm Hg.

It decreases in the arteries as the distance from the heart increases.
It is lower in the capillaries than in the arteries.
It is usually lower in women than in men.

Blood enters the heart because of the 

biology human body and organ system blood pressure circulatory system transportation in animal and plants

  1. Auricular diastole

  2. Ventricular systole

  3. Ventricular diastole

  4. Auricular systole

Show answer
Correct Option: A
Explanation:
Blood enters from superior and inferior vena cava into the right auricle during the relaxation phase of the atrium. The pressure difference between the vena cava and the inside chamber of the right auricle allows the deoxygenated blood to enter the heart. 
So, the correct answer is option A.

Systole brings about the

biology human body and organ system blood pressure circulatory system transportation in animal and plants

  1. Entry of blood into lungs

  2. Entry of blood into heart

  3. Exit of blood from lungs

  4. Exit of blood from ventricles

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Correct Option: D
Explanation:

Systole refer to the contraction phase of the cardiac cycle of the heart between the first and second heart sounds of the cardiac cycle. Systole causes the contraction of the ventricles of the heart leading to ejection of blood into the aorta and pulmonary trunk.
Therefore, the correct answer is option D.

Blood pressure in the veins is lower than that of arteries. The best hypothesis to explain this is that 

biology human body and organ system blood pressure circulatory system transportation in animal and plants

  1. Capillaries offer resistance to the blood flow

  2. Veins are farther from the heart

  3. Most veins carry blood up-hill

  4. Veins have thinner walls than arteries

Show answer
Correct Option: B
Explanation:

The arteries carry blood away from the heart, while veins return blood to the heart. With both, their structure is related to their function. Blood in the arteries is under high pressure generated by the heart. The arteries have thick outer walls and thick layers of muscle and elastic fibers. The blood in veins is under lower pressure than the blood in arteries. The veins have thin walls and thin layers of muscle and elastic fibers. Unlike arteries, veins have one-way valves in them to keep the blood moving in the correct direction.

So, the correct answer is option B.

Blood pressure in the pulmonary artery is

biology human body and organ system blood pressure circulatory system transportation in animal and plants

  1. More than that in the carotid

  2. More than that in the pulmonary vein

  3. Less than that in the vense cavae

  4. Same as that in the aorta

Show answer
Correct Option: B
Explanation:
The blood pressure in the arteries is greater than that in the veins.
Artery > Arteriole > Capillary > Venule > Vein (Vena Cava) 
The pulmonary artery is a short and stout (wide) structure which branches into two parts. On the other hand the pulmonary veins are large blood vessels. Hence, the pressure of blood is greater in the pulmonary artery as compared to that in the pulmonary vein.
So, the answer is B.

Fill in the blanks with suitable words given below:
The instrument used to find out the blood pressure is known as ______

biology human body and organ system blood pressure circulatory system transportation in animal and plants

  1. Serum

  2. Fibrinogen

  3. Hemoglobin

  4. Pulmonary

  5. Sphygmomanometer

  6. Ventricles

Show answer
Correct Option: E
Explanation:

The instrument used to find out the blood pressure is known as a sphygmomanometer. It is a device composed of an inflatable cuff which displays the pressure measured in mm Hg on the mechanical manometer. 

Hence, the correct answer is 'Sphygmomanometer' .

Choose correct alternative in the following statements:
Sphygmomanometer measures

biology human body and organ system blood pressure circulatory system transportation in animal and plants

  1. Pulse rate

  2. Heart beat

  3. Blood pressure

  4. Brain activity

Show answer
Correct Option: C
Explanation:

The sphygmomanometer is a device used to measure blood pressure. It consists of an inflatable cuff, a measuring unit and a mechanism for inflation which may be a manually operated bulb and a valve operated electrically.

Hence, the correct answer is 'Blood pressure' .

Choose the correct answer from the alternatives given.
Drowsiness, felt after a heavy lunch, is due to:

biology human body and organ system blood pressure circulatory system transportation in animal and plants

  1. increased blood pressure

  2. decreased blood pressure

  3. decreased pulse rate

  4. increased pulse rate

Show answer
Correct Option: B
Explanation:

Drowsiness after a heavy lunch is felt due to :

 1. Eating too much-refined carbohydrate induces sugar spikes and crashes, which make us tired.
2. Digestion requires more blood flow to the stomach, hence less blood to the brain, which makes us feel sleepy.
3. Decreased blood pressure termed as postprandial hypotension.

So, the correct option is 'Decreased blood pressure'.

Choose the correct answer from the alternatives given.
Blood pressure is high in and lowest in

biology human body and organ system blood pressure circulatory system transportation in animal and plants

  1. Arteries; veins

  2. Arteries; ventricles

  3. Arteries; relaxed atria

  4. Arterioles; veins

Show answer
Correct Option: C
Explanation:

During systole, because of heart contraction blood is pumped into arteries. Blood pressure is highest as it leaves the heart through the aorta and gradually decreases as it enters smaller and smaller blood vessels (arteries, arterioles, and capillaries). While during atrial diastole, both atria are relaxing, dilating and filling. Blood pressure drops to the lowest level during this state. 

So, the correct option is 'Arteries; relaxed atria'.

Choose the correct answer from the alternatives given.
In an one-circuit circulatory system, blood pressure:

biology human body and organ system blood pressure circulatory system transportation in animal and plants

  1. cannot be determined

  2. is higher at the intestinal capillaries than at the gill capillaries

  3. drops significantly after gas exchange has taken place

  4. is constant throughout the system

Show answer
Correct Option: C
Explanation:
In a single-circuit circulatory system as seen in fishes, the oxygenated blood from the gills does not enter the heart. The heart does not receive oxygenated blood, so known as venous heart. It is directly distributed in the entire body, after which it loses its pressure due to the absence of pushing force. Only the deoxygenated blood enters the auricle and then the ventricle. The deoxygenated blood enters the gills for oxygenation from the ventricle. Blood has a slow flow and low pressure.
So, the correct option is 'drops significantly after the gas exchange has taken place'.