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 phenylketonuria, Q. What is Phenylketonuria? The essential amin...

Q. What is Phenylketonuria? The essential amino acid phenylketonuria is utilized for tissue protein synthesis and hydroxylated to form tyrosine. The hydroxylation reaction requ

Tolerance range, organism that have wide tolerance range

organism that have wide tolerance range

Of which substances is chromatin made, Of which substances is chromatin mad...

Of which substances is chromatin made? Chromatin is made of DNA molecules associated to proteins known as histones. Cell Nucleus Review - Image Diversity: chromatin

Define about ecological models, Why do ecological models commonly have limi...

Why do ecological models commonly have limited applications? The applications of ecological models are limited due to the models are normally very simple and do not accurately

Does the dna replication occur in the cell division, Q. Does the DNA replic...

Q. Does the DNA replication occur in the cell division? Yes. The DNA replication occurs in mitosis as well in the meiosis.

Explain marine oils, Marine oils These oils typically contain large amo...

Marine oils These oils typically contain large amounts of long - chain omega-3-polyunsaturated fatty acids, with up to six double bonds and they are usually rich in vitamins A

Reciprocal crosses , RECIPROCAL CROSSES Similar results were obtained w...

RECIPROCAL CROSSES Similar results were obtained with reciprocal crosses also. A reciprocal crosses involves the same traits but carried by sexes opposite to those in the origi

What is the functional unity of the kidneys, What is the functional unity o...

What is the functional unity of the kidneys? The functional (filtering) unity of the kidneys is the nephron. A nephron is made of afferent arteriole, efferent arteriole, glomer

Essay, Need an essay in regard to an experiment that I did. Essay Assignm...

Need an essay in regard to an experiment that I did. Essay Assignment: Experimental Design Now that you have completed several hands-on lab experiments, take a little time to con

Name, what''s you''re name

what''s you''re name

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