Question

In: Anatomy and Physiology

1. Which of these answers are correct The first heart sound, "lubb," is caused by the...

1. Which of these answers are correct

The first heart sound, "lubb," is caused by the ________.

closing of the atrioventricular valves

closing of the semilunar valves

regurgitation of the atrioventricular valves

blood flowing into the ventricles

2. Choose the right answer:

The plateau phase of the ventricular action potential is caused by _______.

slow K⁺ channels opening

fast Na⁺ channels opening

fast voltage-gated Ca²⁺ channels opening

slow voltage-gated Ca²⁺ channels opening

3.. How is heart rate controlled?

Parasympathetic and sympathetic divisions of the ANS control heart rate.

Heart rate is controlled through the cardiac plexus.

Dual innervation controls the heart rate.

All the listed answers are correct.

Solutions

Expert Solution

1.Correct answer is option A - closure of atrioventricular valves.

Explanation :

First heart sound - Lubb is due to closure of atrioventricular valves.

Second heart sound - Dubb is due to closure of semilunar valves.

2.Right option is - opening of voltage gated slow calcium channels

Expalnation :

Plateau phase is due to opening of voltage gated slow calcium channels.

Depolarisation phase is due to opening of voltage gated fast sodium channels

Repolarisation is due to opening of voltage gated potassium channels and closing of calcium channels

3.Right option is - all the above

Expalnation :

All options are indicating same thing - Heart rate is controlled by sympathetic and parasympathetic divisions of ANS.

Dual nerve supply indicates - sympathetic and parasympathetic supply

Cardiac plexus -plexus of nerves seen at the base of heart. They are branches of parasympathetic and synthetic system.

Sympathetic system increase heart rate and parasympathetic system decrease heart rate.

Sydney Mullin answered 1 year ago

Next > < Previous

Related Solutions

A patient has a heart murmur that occurs after the first heart sound. Given the fact...

A patient has a heart murmur that occurs after the first heart sound. Given the fact that the problem is on the right side of the heart, explain in detail a possible cause of the murmur in terms of the events of the cardiac cycle.

The two major heart sounds are the first sound is a) Lub - it occurs due...

The two major heart sounds are the first sound is a) Lub - it occurs due to turbalnce caused by closure of mitral and tricuspid valves at the start of the systole. The second heart sound is b)Dub- It is caused by causes by closure of arotic and pulmonary valves corresponds to end of the systole. 1. Typical resting heart rate corresponds to 60 to 100 beats per minute.That is during the rest heart beat ranges from 60 to 100...

1. Which of the following statements is correct? a. All the answers are correct. b. The NPV...

1. Which of the following statements is correct? a. All the answers are correct. b. The NPV cannot be used effectively for projects with unconventional cash flows. c. The decision criterion for the accounting rate of return is consistent with the goal of shareholder wealth maximization. d. The NPV provides a direct (dollar) measure of how much a capital project will increase the value of the firm. e. The process of limiting, or rationing, capital expenditures among possible projects is called...

PLEASE GIVE THE CORRECT ANSWERS 1)Which of the following is NOT a determinant of the price...

PLEASE GIVE THE CORRECT ANSWERS 1)Which of the following is NOT a determinant of the price elasticity of demand? A) the availability of potential substitutes B) the share of the budget spent on the item C) the time the consumer has to adjust to the price change D) the cost to produce the product 2)Which of the following will cause a rightward shift of the demand curve? A) a decrease in the cost of production B) a decrease in the...

Congenital heart disease means that the infant was born with a heart defect. The sound of...

Congenital heart disease means that the infant was born with a heart defect. The sound of this can be devasting until it is understood what exactly the defect is? What stage of development is the heart developed in the fetus? There are two types of heart defects cyanotic and acyanotic. Explain what each means by describing blood flow? How is it flowing and why it is cyanotic or not? How do these defects complicate neonatal assessment and oxygen delivery?

In correct sequence, which heart chambers, heart valves, and blood vessels would a drop of blood...

In correct sequence, which heart chambers, heart valves, and blood vessels would a drop of blood encounter from the time it flows out of the right atrium until it reaches the aorta? tricuspid valve, right ventricle, pulmonary valve, pulmonary arteries, pulmonary veins, left atrium, bicuspid valve, left ventricle, aortic valve bicuspid valve, right ventricle, pulmonary valve, pulmonary veins, pulmonary arteries, left atrium, tricuspid valve, left ventricle, aortic valve tricuspid valve, right ventricle, aortic valve, pulmonary veins, pulmonary valve, pulmonary arteries,...

1. Which of the following apply to nylon? One or more answers are correct and you will...

1. Which of the following apply to nylon? One or more answers are correct and you will receive negative points for incorrect answers. A compound with two carboxylic acid groups is reacted with a compound with two amine groups. The product forms as a fiber between two immiscible liquid layers. The product of the reaction is a solid collected by vacuum filtration. A free radical is used to get styrene molecules to bind to each other. 2. Which of the following...

1. Which of the following statements are true regarding muscle glycogen. There are multiple correct answers....

1. Which of the following statements are true regarding muscle glycogen. There are multiple correct answers. If exercise is not to be repeated within 12 hours, then glycogen restoration does not have to be immediately following exercise The most rapid repletion of glycogen following exercise occurs in the first few hours post exercise. Consuming some protein along with carbohydrate during immediate recovery from exercise is beneficial. Higher glycemic index foods enhance glycogen restoration following exercise It is best to always...

Which of the following is/are correct regarding interest rates? Choose all the correct answers. a. Borrowers’...

Which of the following is/are correct regarding interest rates? Choose all the correct answers. a. Borrowers’ preference for long duration and lenders’ preference for short duration causes the term premium to be positive. b. Zero-coupon bonds are less sensitive to interest rate changes compared to coupon bonds with the same time to maturity. c. The yield curve is usually flat. d. Bonds with greater default risk typically trade at lower yield-to-maturities. e. An inverted yield curve serves as a negative...

Which of the following are independent trials? a. All of these answers are correct. b. The...

Which of the following are independent trials? a. All of these answers are correct. b. The results of a coin flip after rolling two dice and the first character of a license plate and the color of the car. c. The results of a coin flip after rolling two dice d. The first character of a license plate and the color of the car e. The total of two dice after recording the value of the first die rolled

Subjects