Budding is considered as an asexual mode of reproduction which is quite prevalent in lower animals. In budding, like any other asexual mode of reproduction no specialized organs are developed in the parent's body to produce specialized cells known as gametes. In budding, a mass of cells simply bulges out from the parent's body and detaches itself from the parent. Once it detaches from the parent it starts to develop as an independent organism. Here, it may be noted that the outgrowth which bulges out from the parent is produced through mitosis not meiosis.
Also, hydra shows a very good regeneration power however this is not a mode of reproduction in hydra. Regeneration is simply a characteristic feature of hydra.
When limiting factors increase, diversity in populations decreases. In this sense "limiting factors" can be anything from a lack of resources to a lack of food, meaning it's harder for the population to survive.
One example of passive transport is diffusion, when molecules move from an area of high concentration (large amount) to an area of low concentration (low amount). Molecules are said to naturally flow down their concentration gradient
