explain the comparative study of digestive and circulatory system of frog cockroach earthworm and humans .pls its very urgent

Comparative study of digestive system of frog, cockroach, earthworm and humans:
Frog Cockroach Earthworm  Humans
The digestive system of frog is similar to that of other vertebrates. It starts with a mouth consisting of teeth for grinding of food. The food is then passed to an opening called oesophagus. From oesophagus food passes to stomach and then to small intestine where required nutrients are absorbed from the chime. The digestive system of cockroach includes alimentary canal and two pairs of salivary glands. The food is ingested through the mouth which leads to oesophagus. Oesophagus opens into sac-like crop used to store food on temporary basis. Crop is followed by gizzard used for grinding of food. For secretion of digestive juices, some 6-8 tubules known as hepatic caecae are present and for removal of nitrogenous waste from the body fluids, malphigian tubules are present. The remnants are expelled from the anus. It has a one-way digestive system. Food enters through the mouth. It is stored in the crop and remains there till the time it gets emulsified in the gizzard by soil particles. An unconvoluted intestine is present for breakdown and absorption of nutrients. The waste material is ejected out from the anus. The human digestive system is a complex organ system within multicellular organisms. It takes in food, passes it to oesophagus, then to stomach and from there to small intestine. The faecal matter is ejected through anus. The gatrointestinal tract of humans is about 20 feet long and is divided into foregut, midgut and hindgut. This tract plays a significant role in digestion.

Comparative study of circulatory system of the following:
                         Frog    Cockroach              Earthworm             Humans
Frogs have closed-circulatory system (blood confined to heart and blood vessels). Heart is three-chambered with two auricles and one ventricle, and is covered by pericardium. Blood consists of plasma, erythrocytes, leucocytes and thrombocytes. Right atrium receives blood from major veins called vena cavae. Blood is pumped to all parts of the body by heart through arteries. Veins collect the blood from all parts of the body to the heart. Cockroach has an open blood-vascular system. A fluid known as haemolymph is present which fills the body cavity haemocoel. Heart is an elongated muscular tube,  differentiated into 13-chambers, each with a pair of ostia. Ostia helps in the flow of blood from haemocoel to heart. Earthworm has closed circulatory system with four pulsatile hearts present in 7th, 9th, 12th and 13th segments of the body. Blood circulates in one direction by contractions of heart. Blood glands produce the blood cells and haemoglobin. Blood cells present are phagocytic. Human circulatory system consists of a pumping organ called heart, blood vessels (arteries, veins and capillaries), blood (circulating fluid) and lymph (tissue fluid). The human heart has four chambers; two auricles and two ventricles. Heart is enclosed in pericardium (double walled sac). The circulation in humans is called double circulation. In this two separate pathways are followed and there is no mixing of oxygenated and deoxygenated blood.

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