Cardiac output and its determination, Biology

Assignment Help:

The cardiac output is the volume of blood pumped from the heart every minute. It is obtained by the volume pumped with each beat (stroke volume) multiplied by the heart rate. The cardiac output increases during exercise and falls in the common type of heart failure. The stroke volume depends in part on the amount of blood in the ventricule at the end of diastole. This determines the degree of stretch of the myocardial fibre. The greater the stretch (within limits) the stronger the force of contraction and the greater the stroke volume (Starlings law of the heart).

Control of the heart rate depends on the ratio of the sympathetic (increases) and parasympathetic (decreases) impulses to the sino atrial node which  is the cardiac pacemaker. Receptors sensitive to pressure are located in the carotid sinus and the wall of the arch of the aorta.When the carotid sinus detects a sudden  rise in arterial pressure, impulses pass from the carotid baroreceptors to the cardiac control centre in the medulla and impulses sent through the parasympathetic system reduce the heart rate. Similar effects result from  the aortic baroreceptors as well. If the blood pressure drops the heart rate is reflexly increased. Various other reflexes from anger, fear, pain, temperature, etc. also increase the heart rate.


Related Discussions:- Cardiac output and its determination

What is function of gamaaminobutyric acid, Q. What is function of Gamaamino...

Q. What is function of Gamaaminobutyric acid? GABA is the principal inhibitory transmitter in the brain. The concentration of GABA is up to 1000 times greater than that of oth

How are secondary cell walls different from primary cell, How are secondary...

How are secondary cell walls different from primary cell walls? Primary cell walls are assembled on the surface of the plasma membrane whereas the cell is growing. They can gro

Explain faecal coliforms - microbiological study of water, Explain the Faec...

Explain the Faecal Coliforms - Microbiological Study of Water? The faecal coliforms include a wide range of bacteria, many of which are not primarily the intestinal bacteria. T

+illustrate sturdy evolutionary hypothesis, Q. Why is it a sturdy evolution...

Q. Why is it a sturdy evolutionary hypothesis that although viruses are the structurally simplest beings they were not the first living beings? The fact that viruses are obliga

Agro industrial-packaging, Packaging Compound feeds, whether in mash o...

Packaging Compound feeds, whether in mash or pellet form, are packed in bags or stored in bins. Bags may be filled directly from mixers, pellet coolers or holding bins and wei

What are the female pronucleus, What are the female pronucleus and the male...

What are the female pronucleus and the male pronucleus? The female pronucleus is the proper haploid nucleus of the egg cell. Male pronucleus is the haploid nucleus of the sperm

Coronary angiography, Q. Can you explain about Diagnostic coronary angiogra...

Q. Can you explain about Diagnostic coronary angiography? Diagnostic coronary angiography has become one of the primary components of cardiac catheterization. In a coronary ang

Explain the importance of vitamin E, Explain the Importance of Vitamin E ...

Explain the Importance of Vitamin E Vitamin E has a pronounced antioxidizing effect. Because of this property, vitamin E decreases the basic metabolism of the tissues or the ox

Define issues that are covered by nutrition economics, Define issues that a...

Define issues that are covered by nutrition economics? The issues that are covered by nutrition economics include: 1. Quantities of food commodities and their development in

Write Your Message!

Captcha
Free Assignment Quote

Assured A++ Grade

Get guaranteed satisfaction & time on delivery in every assignment order you paid with us! We ensure premium quality solution document along with free turntin report!

All rights reserved! Copyrights ©2019-2020 ExpertsMind IT Educational Pvt Ltd