circulation patterns, Biology

Assignment Help:

Circulation Patterns

All vertebrates have some similarities in their circulatory systems but as vertebrate life changes from aquatic to terrestrial, the pattern of circulation becomes more complex. Fish and mammals represent two extremes in vertebrate circulation and Fig. 3.6 compares the two. The principal difference is in heart structure, from two chambered in fish to four chambered in mammals. The fish heart contains two main chambers in series the atrium or auricle and the ventricle. There are two subsidiary chambers (not shown in Figure) the sinus venosus which proceeds the atrium and conus arteriosis which comes after the heart.

These contain valves that prevent backwards flow of blood. Blood makes a single circuit from the heart to the gills where it is' oxygenated and then to the dorsal aorta to be distributed to the body from where it returns to the heart by the veins. Such a system has the advantage that all of the blood going to the body has already been oxygenated in the gills. However, there is a disadvantage i.e. the narrow gill capillaries slow down the blood flow resulting in a low blood pressure. This slows the rate of oxygen delivery to the cells and limits the metabolic rate that fish can attain.

1674_Circulation Patterns.png

                              Figure:  Circulatory system pattern in (a) fish and (b) mammals. Rust shows oxygenated blood


Related Discussions:- circulation patterns

Conditions requiring rapid treatment of hypertension, List of Conditions Re...

List of Conditions Requiring Rapid Treatment of Hypertension 1) Cardiac: • Acute aortic dissection • Acute left ventricular failure • Acute or evolving myocardial i

Cardiac care on admission for operation, Cardiac Care on Admission (First t...

Cardiac Care on Admission (First two hours) ECG is monitored by more than one lead (three to five). Left atrial pressure, arterial BP, central venous pressure, respiration

Deficiency diseases-vitamin- d deficiency, Vitamin- D deficiency Anima...

Vitamin- D deficiency Animals obtain vitamin D either through the diet or when skin is exposed to solar radiation. The deficiency of vitamin D is associated with reduced absor

Explain about the weight cycling - energy balance, Explain about the Weight...

Explain about the Weight cycling - energy balance? There are a number of obese people who keep losing and gaining weight a number of times in their lives. This is called the Yo

Imaging techniques to test stress, Q. Imaging Techniques to test stress? ...

Q. Imaging Techniques to test stress? A screening exam with M-mode and limited Doppler should be performed at the start of the test, but a detailed echo examination is usually

Determine the foos sources of cyanocobalamin, Determine the Foos Sources of...

Determine the Foos Sources of cyanocobalamin? Vitamin B I2 is unique among vitamins in the sense that it is mostly found in foods of animal origin but is not generally present

Preformation theory - pre-mendelian theory, Preformatio n Theory (1632-172...

Preformatio n Theory (1632-1723) (i)         Scientist 'Malpighi Swammerdam' propounded the preformation theory. This theory holds that the sex cells (sperm and ova) had the m

What is signifying by binomial nomenclature, Q What is signifying by binomi...

Q What is signifying by binomial nomenclature and what are its basic rules? Scientific nomenclature of a species must have at least two names one that classifies it as genus an

Define source of electrons - growth of microorganism, Define Source of Elec...

Define Source of Electrons - Growth of Microorganism? Depending upon the source of electrons used by microorganisms, these are known as - a) Lithotrophs (rock eaters) - use

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