Transport System in Multi Cellular Organisms

Running head: BIOLOGY
Biology
Name of the Student
Name of the University
Author Note

1BIOLOGY
Table of Contents
Task 3.........................................................................................................................................2
M2..........................................................................................................................................2
Answer a.............................................................................................................................2
Answer b............................................................................................................................2
Task 4.........................................................................................................................................7
M3..........................................................................................................................................7
Answer a.............................................................................................................................7
Answer b............................................................................................................................7
References................................................................................................................................12

2BIOLOGY
Task 3
M2
Answer a
The main transport system in multi-cellular organisms is circulatory system. It helps
in the transport of the nutrients to the body tissues. Circulatory system also transports waste
products to the cells to the excretory system and aids in the conduction of hormones from one
part of the body to another. The unicellular organism has single cell as opposed to multi-
cellular organism and thus they do not need a complex circulatory system as their circulation
occurs via diffusion (Noordergraaf 2012).
Answer b
Transport of Blood
The circulation of the blood inside the body is maintained by systemic circulation and
pulmonary circulation. Pulmonary circulation supplies blood the lungs and systemic
circulation supplies blood rest of the body other than the pair of lungs. Systemic circulation is
also termed as peripheral circulation or greater circulation. The transport of the blood
towards the lungs for the process of purification is known as pulmonary circulation.
The arteries transport blood under high pressure. The transportation occurs towards
the tissues and thus arteries have strong vascular walls. In the arterial system, the arterioles
are the terminating smaller branchces. They control special conduits via which the blood
transported and released into the capillaries. Capillaries help in the exchange of fluid,
electrolytes, nutrients, hormones and other substances. This exchange occurs between
circulating blood and interstitial fluid. Thus, the walls of capillaries are thin. Veins act as
conduits that assist in transportation of blood from the venules towards the heart. They also

3BIOLOGY
act as the major reservoir of extra blood. Since the blood pressures inside the veins are low,
the venous walls are thin (Stanfield 2012).
Figure: Distribution and Circulation of Blood in different parts of the respiratory
system
(Source: Hall 2015)
Transport of Lymph
The flow of the lymph takes place via the lymphatic system. It is the exchange of
fluid that occurs between the interstitial space and blood. Thus lymphatic system is also
represented as an accessory route. One of the main function of the lymphatic system is it
carries large particulate matter and proteins away from the tissue spaces. The importance here
lies in the fact that neither of these can be removed via absorption from the capillaries. All the
tissues that are present inside the body have lymph channels. Lymph channels directly drain
out excess fluid into the interstitial spaces. However, there are exceptions like superficial