Question
The diagram shows a section of a human vein.
What is the function of the part labelled X?
(A) to make sure the blood flows to the heart
(B) to make sure the blood flows to the kidneys
(C) to make sure the blood flows to the brain
(D) to make sure the blood flows to the lungs
▶️Answer/Explanation
Ans : A
The correct answer is A, because :
Human vein carries blood from tissues to the heart.
Main distinguishing feature between artery and vein is presence of valves in the veins.
These valves helps in single directional blood flow, even against the gravity.
And as veins, carries blood from tissues to heart, then valves helps in that function.
So, answer is A
Question
The diagram shows the outside of a human heart.
Which structure is a coronary artery?
▶️Answer/Explanation
Ans: D
The correct answer is D, because :
Coronary arteries carries, oxygenated blood to the heart tissues, with help of its branches.
Whereas, marked other blood vessels are :
• A – Superior Vena Cava
• B – Aorta
• C – Pulmonary artery
Question
Heart muscle cells have a high rate of metabolism. Which structure do they require to be present in high numbers?
A chloroplasts
B mitochondria
C cell walls
D vacuoles
▶️Answer/Explanation
Ans B
The correct answer is B, because :
• Chloroplasts are found in plant cells, which helps in synthesis of glucose (food source)
• Mitochondria are called as power house of the cells, as they produce ATP for cellular functions.
• Cell wall is present in plant cells, but not in animal cells and also gives protection to internal structures of cells.
• Vacuoles are needed to function as storage organelle but not in energy production.
Here, heart muscle is with high rate of metabolism which means it needs high energy production, so mitochondria (power house of the cell) is required in large number.
Question
What are methods for monitoring the activity of the heart?
▶️Answer/Explanation
Ans D
The correct answer is D, because :
Heart activity is monitored through the ECG, Pulse Rate and also Heart sounds.
• In ECG, based on the heart activity, a graphical representation is produced and if any abnormity is noted it gets indicated in graph.
• Pulse rate is the total number of times a heart beats in a minute.
• Heart sounds are produced by closure of valves and their closure at regular intervals with regular frequency helps to monitor proper heart function.