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

Describe what types of results describe hypothesis, Why did giraffes develo...

Why did giraffes develop long necks? 1) Describe an experiment to test this hypothesis. Be explicit about the methods you will use, the setting, the time that the experiment wil

What is the gross primary production of an ecosystem, Q. What is the gross ...

Q. What is the gross primary production of an ecosystem? How does GPP relate to photosynthesis? The Gross primary production of a GPP or ecosystem is the quantity of organic ma

Determines the concentration of cortisol in the blood plasma, If one determ...

If one determines the concentration of cortisol in the blood plasma to be 10 micrograms/mL and that in a 24 hour period a person excretes 10 mgs of cortisol, calculate the volume o

Explain economic status of diet, Economic Status Economic Status  :  I...

Economic Status Economic Status  :  It is one of the important practical considerations to be kept in mind while  formulating  a diet prescription. During  an acute illness, a

What do you mean by transition period, Q. What do you mean by Transition Pe...

Q. What do you mean by Transition Period? The transition period from the Renaissance to the Modern period produced many notable workers and much literature. Botanists gradually

Define about the concept of sports nutrition, Define about the concept of s...

Define about the concept of sports nutrition? The concept of sports nutrition was evolved fundamentally with integration of different disciplines in order to collectively striv

An experiment to test the hypothesis, How would you design, in principle, a...

How would you design, in principle, an experiment to test the hypothesis that a certain variety of lettuce seed needed daylight in order to germinate?  You would need as large

Define lipids - tests for presence of exoenzymatic activity, Define Lipids ...

Define Lipids - Tests for Presence of Exoenzymatic Activity? Lipids are also high molecular weight compounds. Enzyme lipases (esterases) cleaves the ester bond to form glycerol

Discuss in detail about the close head injuries, Discuss in detail about th...

Discuss in detail about the Close Head Injuries Closed-head injuries result from a blow to the head, which can subject the brain to a variety of mechanical forces: Damag

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