Answer:
A) receptor, sensory neuron, interneuron, motor neuron, effector 
Explanation:
In a reflex arc, the receptors present in the skin receive stimulus and generate afferent impulse. The sensory neuron transmits the impulse to the interneuron. Interneuron is present in the spinal cord and activates it. The interneuron then sends back the impulse through the motor neurons to effectors whcih are present in the muscles for the response.
 
        
             
        
        
        
In the heart, the valves are located between atria and ventricles and between ventricles and arteries (option D). 
<h3>What are valves in the heart?</h3>
Valves are membranous partitions which permit the passage of the contents of a vessel or cavity in one direction, but stop or control the flow in the opposite direction.
Valves in the heart enforce a one-way blood flow through the heart and separate atria from ventricles, and ventricles from the large arteries that leave them.
The four valves in the heart and their location is as follows:
- tricuspid valve: located between the right atrium and the right ventricle
- pulmonary valve: located between the right ventricle and the pulmonary artery
- mitral valve: located between the left atrium and the left ventricle
- aortic valve: located between the left ventricle and the aorta.
The valves between the atria and ventricles are called atrioventricular valves or cuspid valves while those at the bases of the large vessels leaving the ventricles are called semilunar valves. 
Therefore, it can be said that the valves of the heart are located between atria and ventricles and between ventricles and arteries.
Learn more about valves of the heart at: brainly.com/question/28266922
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Answer:
The correct answers are:
1. closing 
2. the ventricles and arteries, 
3. a constricted trachea
Lub is the first sound of a heartbeat and is mentioned as S1. It is usually produced due to the closing of tricuspid and and mitral or bicuspid valves present between atria and ventricles. 
Tricupsid is located between atrium and ventricle of the right hand side and mitral valve is located between atrium and ventricle of the left hand side. They prevent the back flow of blood from ventricles to their respective atria.
Dub, being the second sound is written as S2. It is produced due to the closing of pulmonary (located between right ventricle and pulmonary artery) and aortic valves (located between left artery and aorta). 
These valves prevent the back flow of blood from arteries into the ventricles.
The time between the two sounds is often taken as the measure of the diastole i.e. ventricular filling.
Wheezing refers to a high-pitched sound produced when a person breathes, especially during exhale. It is caused by constriction of the airways or inflammation. It is considered as a symptom of various diseases such as asthma, COPD, allergies, bronchitis etc.