The recent news is that the Frog and Earthworm topics are no longer a part of the syllabus for the NEET from 2021.
So next year also this is not included. In the NEET syllabus the chapter which talks of structural organisation in animals, the frogs and earthworm is not included and the only thing included is the morphology, anatomy and functions. However it is advised to at least have some of the concepts cleared before attempting the exam. There might be a question or two that comprises these topics. When we see earlier years and the trends the questions were very few and this is seen in NEET or AIIMs etc. Just give it a read for one time and this comprises of very small portion. Reading it twice you can remember it more and also this will prepare you for the exam.
The basic things for both the topics can be read and summarised as below:
- The reproductive system for Frog. In the frog which is Male there are two testes and they are joined to the kidneys. There are also efferent ducts for the same. There are also the ureters. The sperm is directly ejected from the cloaca to the eggs and this is when the female lays them.
It is interesting to see that the male frog has certain special sexual characteristics which are predefined before the mating process. They have pads on the thumbs to give him a firm hold. In many of the species it is seen that the male is smaller as compared to the female. The male frogs have vocal chords and when they make a particular sound during the breeding season and specially in some particular species these sacs amplify the sound.
The Frog Nervous System: Frogs have quite highly developed and complex nervous system which has a brain, spinal cord and nerves. The frog brain is usually compared to the humans as complex they are. They have two olfactory lobes, two cerebral hemispheres, two optic lobes, cerebellum and medulla oblongata. The frog muscle coordination is controlled by the cerebellumllum and the medulla facilitates the digestion, respiration and other vital functions. However the size of the cerebrum in the frog is much smaller to the humans. Frogs have ten pairs of nerves that pass information from outside to the brain. Ten pairs of nerves which are spinal nerves which pass information from the outside to the brain.
EARTHWORM: These have circulatory system which are dual in nature and also a closed circulatory system that carry the food, waste and gases. The circulatory system for earthworms has blood vessels numbered five. The Top vessel which does run above the digestive tract, the ventral vessel which tuns below the digestive tract, the sub-neural vessel which runs below the nerve cord and the two other vessels on the either side of the nerve cord.
Some of the earthworms are Parthenogenetic which means the embryo develops without fertilisation. Among some of the earthworms, the process happened from relatives many times. There is another process which happens in some species where the process of mating becomes necessary to stimulate the reproduction process although the male genetic material never passes to the offsprings. The process of mating for earthworms happens in the night time and since earthworms are all hermaphrodites which means they have both male and female sexual organs. Earthworms tend to have one or two pairs of testes inside the sacs and the vesicles present will produce and reelse the sperm via the male pores.
One of the vital functions of the dorsal vessel in the earthworm is that the vessel moves the blood in the direction forward and the other four will carry the blood rearward. In some cases there are arches acting as the heart and pumping blood to the ventral vessel and this thus acts as the aorta. The blood here has cells which are kind of amoeboid and they have haemoglobin dissolved in the plasma. There is a second circulatory system from the cells of the digestive system that line the coelom.
In the case of digestive cells in the earthworms they give out some non living cells constituted of fats into the coelom which has fluid and they float freely. Here they pass through the walls that separates the segments which moves the food to the other parts, They also help in healing wounds.
Important question: Human heart consists of?
- A) Epithelial and connective tissues
- B) Muscular and neural tissues
- C) Connective and muscular tissues
- D) Both A and B