Question

1. Levels of which of the following hormones would be expected to rise if one needed more energy in order to run up some stairs?

thyroid stimulating hormone (TSH)

Somatostatin

growth hormone

ADRENOCORTICOTROPIC

2. The first heart sound occurs at which of the following moments?

the end of isovolumetric contraction

the end of isovolumetric relaxation

the end of ventricular systole WRONG

the end of ventricular diastole

3.Which of the following occurs during the ejection stage of the cardiac cycle? ASK CHEGGS

blood is pumped from the left atrium past the bicuspid valve

blood is pumped from the right ventricle past the aortic semilunar valve

blood is pumped from the left ventricle past that aoritic semilunar valve

blood is pumped from the right atrium past the bicuspid valve

4. Which of the following will cause more oxygen to be released from hemoglobin at the tissues?

low blood temperature

high concentration of hyrogen ions

high oxygen concentration

low carbon dioxide concentration

Answer 1

1) Adrenocorticotropic

• Cortisol is a catabolic steroid in response to excercise and stress.
• It provide energy by the breakdown of triglycerides and protein into glucose , which is a immediete source of energy.
• ACTH ( adrenocorticotropic hormone ) produced more when there is less level of cortisol in the blood.
• so inorder to raise the level of cortisol, ACTH in the blood is raised.
• ACTH is produced by anterior pituitary gland.
• Rest all other hormone have different function , hence it is wrong.

2) The end of isovolumetric contraction period

• first heart sound resembles like the word lub
• It is long, soft and low pitched sound.
• It occur due to sudden closure of atrioventricular valves.
• Duration of sound is 0.10-0.17 second.
• hence all other options are wrong.

3) blood is pumped from the left ventricle past that aoritic semilunar valve

• Ejection begins with increase in intraventricular pressure , which exceeds with pressure inside the aorta and pulmonary artery.
• This causes opening of aortic and pulmonary semilunar valves
• Blood from left ventricle pass into aorta by passing through aortic semilunar valve
• Blood from right ventricle pass into pulmonary artery through pulmonary semilunar valve.
• Rest all other option occur in other stage and 2nd option is wrong because blood from right ventricle should pass through pulmonary semilunar valves.

4) high concentration of hyrogen ions

• Increase in hydrogen ions means decrease in pH.
• Since carbon dioxide react with water to form carbonic acid, there will be an increase in carbon dioxide causing decrease in pH
• As a result haemoglobin release oxygen.
• Rest of other option are wrong because it causes picking up of oxygen by haemoglobin.