Answer:
Gastrovascular Cavity
Explanation:
Hydra is commonly found in freshwater ponds and ditches as solitary organisms, in underside of aquatic leaves and lily pads in cool,clean freshwater pools and streams. It has a *Cylindrical body shape*.
Hydra possesses an internal body cavity, the *Gastrovascular cavity *,lined by gastrodermis and has a single opening,the mouth,which serves as an anus.
The Gastrovascular cavity of Hydra is a site for *digestion and nutrient distribution*,and also serves as anus.
Explanation:
In the megasporan- gium of each ovule, the megasporocyte divides by meiosis, producing four megaspores. One survives and forms a female gametophyte. Fertilization: In nucleus of developing endosperm-- Double fertilization occurs. One sperm fertilizes the egg, forming a zygote.
Answer: Keystone species
Explanation: A keystone species is a species which occupied a niche so central in the ecosystem that it has a disproportionately large effect on its environment and other species in it.
The coral's function in its ecosystem is so vital that if you were to remove it, the entire community would be drastically altered beyond recognition.
The coral serves as the base structure of its ecosystem.
That is to say that many corals are hermatypic(they form reefs). This reef serves as the environmental structure of the Coral's ecosystem. Built in and around it is a very biodiverse biotic environment. The coral not only serves as a hiding place and habitat for many marine organisms including fish, clams, lobsters, etc. It serves as resting place for larger animals like turtles and also serves as hunting sites for other animal species.
The most common way of determining a keystone species, is to see what happens when that species is removed from the ecosystem. Coral have shown to be so central to their ecosystem that the bleaching of coral reefs due to tourism and climate change causes a massive loss to biodiversity. And this is quite significant as reefs are the most biodiverse marine habitats.
well there will be no one hunting the seals so the seals will over populate also some fish will to
Answer:
The correct answer is option D. True tissues.
Explanation:
The cell that made sponge does not form the tissue however sponge have cells that play important role and specific for specific function but does not have true tissues.
In other animal phyla cells form tissue or organ or organ systems and called as true tissues.
Thus, the correct answer is option D. True tissues.
