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

Explain requirement for simple staining of bacterial culture, Explain Requi...

Explain Requirements for Simple Staining of Bacterial Cultures Culture: 24 hours bacterial culture of E. coli and Bacillus on nutrient agar or in broth. Reagents: Methylene

Classification, Tricks of learn a classification (molusca,arthopoda,prifera...

Tricks of learn a classification (molusca,arthopoda,prifera etc.)

Ecological isolation, Ecological isolation is based on the fact that popula...

Ecological isolation is based on the fact that population shows preference to one habitat over the other. This extensive forests become barriers to the dispersal of organims living

Explain changes in body tissue compartments - underweight, Explain the Chan...

Explain the Changes in Body Tissue Compartments - Underweight? The severity of nutritional deprivation determines the extent of changes in the body tissue compartments. The fir

Emergency treatment of diarrhoea, Q. Emergency treatment of diarrhoea? ...

Q. Emergency treatment of diarrhoea? Emergency treatment and drug treatment: Severe dehydration is fatal and requires intravenous fluids and hence hospitalization. You have re

Explain the history of darwins finches, Explain the history of Darwin's Fin...

Explain the history of Darwin's Finches? The most well known evidence upon which Darwin based his theory was the distribution pattern of the Galapagos finches. The Beagle's voy

Peripatric speciation, Peripatric Speciation Speciation by small populat...

Peripatric Speciation Speciation by small populations isolated on the periphery of the distribution of the parent population can be described as peripatric speciation. Small, pe

What is optic nerve, What is optic nerve The optic nerve contains more...

What is optic nerve The optic nerve contains more than one million axons that initiate in the ganglion cell layer of the retina. This structure originatcs at the back of the e

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