During the mature stage this happens because the air becomes more dense.
They lay eggs because they don't have the genetics or things in their body to give birth.
The complete statement is this: CNIDARIA exhibit two radial body forms, the polyp and the medusa, and use stinging cells to capture prey.
Cnidaria is categorized under the Animalia kingdom. It is made up of more that eleven thousand species, which all live in aquatic habitats; either fresh or salt water environments. There are four basic classes of cnidarians, these are: Anthozoa, Cubozoa, Scyphozoan and Hydrozoa. Their common feature is the cnidocytes, which are specialized cells that they use to capture their preys.
Cnidaria have two radial body types, which are called polyp and medusa. They used cnidocytes (stinging cells) to capture the foods they feed on.
The correct answers are as follows:
1. A.
There are basically two types of succession, they are primary and secondary succession. Primary succession refers to the type of succession that occurs in new and bare areas where the soil present is unable to sustain the growth of plants. An example of primary succession area is an area with sand dunes that is freshly formed. Primary succession usually occur over a long period of time. Secondary succession is a type of succession that occur on a land which was disturbed by hazardous events such as fire outbreak, flood, etc. Secondary succession occurs much faster than the primary succession.
2. D
There are two types of factors that affect any particular ecosystem, these are abiotic and biotic factors. The abiotic factors refers to non living factors such as temperature, relative humidity, rainfall, etc. while the biotic factors refer to the living factors. Looking at the options given above, one will see that only option D has living factor, which is predators. All other options have abiotic factors.
Each DNA strand within the double helix is a long, linear molecule made of smaller units called nucleotides that form a chain. The chemical backbones of the double helix are made up of sugar and phosphate molecules that are connected by chemicals bonds, known as sugar phosphate backbones.
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