Question

Сравнительная характеристика пресноводной гидры и белой планарии:Слои клетокпитание и пищеварениедыханиевыделениенервная система и органы чувствразмножениерегенерация

Answer 1

Гидра 
строение пресноводной гидры 
1-эктодерма
2-энтодерма
3-мозоглея 
4-подошва 
5-кишечная полость
6-почка
7-щупольце
8-рот
(не по порядку просто перечисление)

разрез гидры 
1- эпителиально-мускульные клетки
2-промежуточная клетка
3-стрекательная клетка
4-нервная клетка 
5-пищеварительно-мускольная клетка
6-железистая клетка
7-мезоглея

если дотронуться до гидры или уколоть иголкой она сожмется.это происходит потому,что сигнал полученый даже 1-ой нервной клетки распостронится по всей нервной сети.

Answer 2

Comparative Characteristics of Freshwater Hydra and White Planaria:

Cell Layers: - Freshwater Hydra: Hydra is a multicellular organism that consists of two cell layers: an outer layer called the epidermis and an inner layer called the gastrodermis. The space between these two layers is called the mesoglea [[1]]. - White Planaria: White planaria, also known as flatworms, have three cell layers: an outer layer called the epidermis, a middle layer called the mesoderm, and an inner layer called the endoderm [[2]].

Feeding and Digestion: - Freshwater Hydra: Hydra is a carnivorous organism that feeds on small aquatic invertebrates, such as small crustaceans and worms. It has specialized cells called cnidocytes that contain stinging structures called nematocysts, which are used to capture prey. Once captured, the prey is engulfed by the hydra's tentacles and digested in its gastrovascular cavity [[3]]. - White Planaria: White planaria are also carnivorous and feed on small organisms, such as protozoans and small worms. They have a muscular pharynx that extends from their mouth, which they use to suck in food. The food is then digested in their gastrovascular cavity [[4]].

Respiration: - Freshwater Hydra: Hydra obtains oxygen through diffusion across its body surface. As a small organism, it has a high surface-to-volume ratio, which allows for efficient gas exchange with the surrounding water [[5]]. - White Planaria: White planaria also obtain oxygen through diffusion across their body surface. They have a flattened body shape, which increases their surface area for gas exchange [[6]].

Excretion: - Freshwater Hydra: Hydra eliminates waste products, such as ammonia, through diffusion across its body surface [[7]]. - White Planaria: White planaria excrete waste products, such as ammonia, through specialized excretory structures called flame cells [[8]].

Nervous System and Sensory Organs: - Freshwater Hydra: Hydra has a simple nervous system consisting of a nerve net. It lacks specialized sensory organs but can detect changes in light intensity and touch [[9]]. - White Planaria: White planaria have a more developed nervous system compared to hydra. They have a pair of eyespots that can detect changes in light intensity and a network of nerve cells that coordinate their movements [[10]].

Reproduction: - Freshwater Hydra: Hydra can reproduce both sexually and asexually. Asexual reproduction occurs through budding, where a new individual grows as an outgrowth from the parent hydra. Sexual reproduction involves the release of sperm and eggs, which combine to form zygotes that develop into new individuals [[11]]. - White Planaria: White planaria are hermaphroditic, meaning they have both male and female reproductive organs. They can reproduce both sexually and asexually. Asexual reproduction occurs through fragmentation, where a piece of the planaria's body can regenerate into a new individual. Sexual reproduction involves the exchange of sperm between two planaria, followed by the internal fertilization of eggs [[12]].

Regeneration: - Freshwater Hydra: Hydra has a remarkable ability to regenerate. If a hydra is cut into several pieces, each piece has the potential to regenerate into a complete individual [[13]]. - White Planaria: White planaria are well-known for their regenerative capabilities. They can regenerate their entire body from small fragments, including the head, tail, and internal organs [[14]].

In summary, freshwater hydra and white planaria have some similarities in terms of their feeding and digestion processes, as well as their ability to regenerate. However, they differ in terms of their cell layers, respiratory mechanisms, excretory systems, nervous systems, sensory organs, and modes of reproduction.

I hope this information helps! Let me know if you have any further questions.