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

Explain the nervous system characterized in echinoderms, How are the symmet...

How are the symmetry and the nervous system characterized in echinoderms? Adult echinoderms, with cnidarians, are the animals that present radial symmetry, i.e., their body str

Explain angiosperms and flowering plants, Q. What are the angiosperms, the ...

Q. What are the angiosperms, the flowering plants? What is the major feature that distinguishes them from the gymnosperms? Flowering plants have seeds and flowers (phanerogamic

Define about fusarium - identification of fungi and yeast, Define about the...

Define about the Fusarium - Identification of Fungi and Yeasts? Classification Kingdom - Mycetae Division - Amastigomycotina Subdivision - Deuteromycotina Class - D

Growing leaves in the classroom, Growing leaves in the classroom A swee...

Growing leaves in the classroom A sweet potato will make dense foliage in the classroom if it is placed in water. Set the potato, root end down, in a glass or jar and keep the

What is pulmonary venous congestion ?, Q. What is Pulmonary Venous Congesti...

Q. What is Pulmonary Venous Congestion ? In pulmonary venous hypertension, the earliest change is an increase in calibre of the upper lobe vessels. If the upper lobe veins meas

Edema, Ed e m a It refers to excessive accumulation of fluid in tiss...

Ed e m a It refers to excessive accumulation of fluid in tissue spaces caused by disturbance in the fluid interchange between capillaries, tissue spaces and lymphatic vessel

What do you mean by cancer, Q. What is cancer? The Cancers are malign n...

Q. What is cancer? The Cancers are malign neoplasias that is abnormal and uncontrolled proliferation of cells that can disseminate to other sites of the body. The Cancer dissem

<-- that guy, thy does he look too excited in the illistration?

thy does he look too excited in the illistration?

Explain the repair mechanisms of brain, Explain the repair mechanisms of br...

Explain the repair mechanisms of brain Scientists are just beginning to understand how these innate repair mechanisms might be harnessed to treat disease. On leading edge of th

DNA replication, What is cDNA and what is its function and mechanism of act...

What is cDNA and what is its function and mechanism of action?

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