Prepare for NEET Biology Body Fluids And Circulation (Double Circulation) with MCQs & PYQs on NEET.GUIDE. Access free practice, previous year questions, and expert guidance to analyze separate pulmonary and systemic circuits in mammals.
NEET Questions / Zoology / Body Fluids And Circulation / Double Circulation
A researcher is studying the circulatory system of a newly discovered vertebrate species. They observe that blood passes through the heart twice during one complete circuit around the body. However, they also notice some mixing of oxygenated and deoxygenated blood within the ventricle. Which adaptation is MOST LIKELY present in this species to minimize this mixing?
A four-chambered heart
Complete separation of atria and ventricles
An incomplete interventricular septum
Two separate circulatory circuits for pulmonary and systemic circulation
In a hypothetical organism with double circulation, the volume of blood pumped by the right ventricle per minute is significantly lower than the volume pumped by the left ventricle. Which of the following is the MOST LIKELY explanation for this observation?
The right ventricle is less muscular than the left ventricle.
The pulmonary circuit has higher resistance than the systemic circuit.
The pulmonary circuit has lower resistance than the systemic circuit.
The organism has a defect in its heart valves.
Which of the following scenarios would MOST directly impair the efficiency of double circulation in a mammal?
A decrease in the diameter of systemic capillaries.
Increased blood viscosity due to dehydration.
A hole develops between the left and right atria.
Reduced elasticity of the aorta.
If the partial pressure of oxygen in the alveoli is 100 mmHg and the partial pressure of oxygen in the pulmonary artery is 40 mmHg, what drives the diffusion of oxygen into the blood?
Active transport of oxygen across the alveolar membrane.
Facilitated diffusion by hemoglobin.
The partial pressure difference between the alveoli and the pulmonary artery.
The higher concentration of oxygen in the alveoli compared to the pulmonary artery.
In birds and mammals, double circulation is essential for supporting high metabolic rates. Which of the following BEST explains this relationship?
It increases the overall blood volume in the organism.
It reduces the distance blood needs to travel to reach the tissues.
It prevents the mixing of oxygenated and deoxygenated blood, maximizing oxygen delivery to tissues.
It allows for more efficient removal of carbon dioxide from the body.
A defect in the interventricular septum of a mammalian heart would MOST directly affect which of the following processes?
The rate of heart contractions.
The volume of blood pumped per beat.
The separation of oxygenated and deoxygenated blood.
The flow of blood through the atrioventricular valves.
In double circulation, the oxygenated blood is pumped from the heart to:
The lungs
The right atrium
The right ventricle
The body tissues
What is the main advantage of double circulation?
Slower blood flow
Mixing of oxygenated and deoxygenated blood
More efficient supply of oxygen to the body tissues
Lower blood pressure
Which circuit in double circulation carries deoxygenated blood to the lungs?
Systemic circuit
Pulmonary circuit
Coronary circuit
Hepatic portal circuit
In humans, double circulation involves which two main circuits?
Renal and Hepatic
Pulmonary and Systemic
Coronary and Hepatic
Lymphatic and Systemic
