Answer: Water is drawn in through small openings on a sponge's body called OSTIA.
The supportive skeleton of a sponge contains SPICULES which provide protection from predators.
Explanation:
Sponges refer to any of the aquatic animals of the phyllum porifera which is normally characterized with porous structures and has horn-like calcareous internal framework.
Sponges usually have multiple pores called "OSTIA" on their bodies that allow water to enter them.
Most sponges are sessile and because of this, they can't run away from predators. They usually have sharp "SPICULES" which are part of their skeleton that provide them some certain degree of defense. Apart from this, they also produce toxins which poisons predators that attempt to consume them
It’s called densitydependent. It slowly increases then reaches an exponential growth rate and then declines into the negative until it gets to zero where it stabilizes
The Earth comprises many spheres of subsystems, which associate with each other to develop a composite and spontaneously changing system of the Earth. The processes taking place in the system of the Earth occurs on spatial scales changing from fractions of millimeters to thousands of kilometers, and on time scales, which varies from milliseconds to billions of years.
The examples of instantaneous scales are a rotation of the Earth, breathing, an earthquake.
The examples of long-term scales are making coal and plate tectonics.
The system of the Earth is featured by various overlapping cycles in which matter is recycled again and again. The cycles involve interactions between multiple spheres and systems. The examples of cycles are rock cycle, day and night, and seasons.
Volcanoes discharge a huge concentration of particulate matter into the atmosphere. These particles function as nuclei for the development of droplets of water (hydrosphere). The rainfall, that is, hydrosphere usually upsurges after an eruption, initiating growth of the plant (biosphere). Thus, volcanoes and volcanic activities are a good illustration of system interactions.