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

Define the sun and solar drying method, Define the Sun and Solar Drying Met...

Define the Sun and Solar Drying Method? The make use of solar energy to preserve the food items is mainly the oldest form of food reservation and is still practiced today for f

How many are the pulmonary veins, Q. What and how many are the pulmonary ve...

Q. What and how many are the pulmonary veins? The pulmonary veins are part of the pulmonary circulation they are vessels that carry oxygen-rich (arterial) blood from the lungs

Pheromones serving functions other than reproduction, Pheromones Serving Fu...

Pheromones Serving Functions Other than Reproduction Besides sexual responses as described above pheromones mediate several other types of behaviour. Alarm pheromones have bee

Explain successive trophic levels in the pyramid of energy, What would occu...

What would occur to the successive trophic levels in the pyramid of energy if the rate of reproduction of phytoplankton was slowed down? Suggest two factors, which could cause l

Explain about diabetes mellitus, Q. Explain about Diabetes Mellitus? Di...

Q. Explain about Diabetes Mellitus? Diabetes Mellitus is a metabolic disorder characterized by chronic hyperglycemia (increased sugar) with disturbances of carbohydrates, fats

What are analogies for a nucleolus, What are analogies for a nucleolus? ...

What are analogies for a nucleolus? If the nucleolus is the president of a factory then the nucleolus is the manager

Determine the sarcomere of a skeletal muscle, In the sarcomere of a skeleta...

In the sarcomere of a skeletal muscle, there are A. myosin molecules in the I band. B. both tropomyosin and myosin molecules in the region of the A band that is not in the H

What is leghemoglobin, The  nitrogenase  complex  is  extremely  sensitive ...

The  nitrogenase  complex  is  extremely  sensitive  to  inactivation  by  O2,  so  the enzyme  must be protected  from this reactive  substance.  During the root nodules of legumi

How antigen react against future infection by same agent, Q. How can an org...

Q. How can an organism that once underwent contact with an antigen be immunized against future infections by the same agent? This phenomenon is called as immune memory when an

Hindbrain - cerebellum, HIND BRAIN - 1 .       CEREBELLUM - Li...

HIND BRAIN - 1 .       CEREBELLUM - Little part, lies below the posterior part of cerebrum & above the medulla oblongeta. It conists of median lobe vermis & 2 lat

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