Invertebrates are known as creatures that do not have backbones. Even though these creatures do not have backbones, they have been uniquely designed in order to survive. According to studies, most of these creatures are found in the sea and one of them is the Star Fish or also called as the Sea Star. Starfish's functions and ability to survive is not the same like other animals which make them unique in a different way. The starfish's body is hard and bony for protection purposes and they exist in a variety of colors for camouflage. Their essential functions in order to survive are as follows:
-The Ability to Regenerate: Starfishes have the ability to grow damaged and lost limbs or even their entire body as long as the center part is still present and intact. And this is their way of reproduction as well.
-Having Tube Feet: Its arms are covered with a suction-like tiny cups of tube feet. This unique design of the starfishes enables them to move and secure themselves, especially on rocks and ocean floors.
-Unique Feeding Ability: Sea Stars don't have mouths nor teeth to ingest food. Rather, these creatures have the ability to push open or turn their stomachs out and digest its food. After digestion, their stomachs retract back to their bodies.
-Vascular System: How starfishes survive does not rely on having hearts, brains and blood. Rather, they use the seawater. The seawater serves as the one the circulates inside the sea stars' bodies and this is when nutrients and oxygen are being transported and absorbed.
Answer:
A.
Explanation:
The arctic soil is so cold that the ground beneath the tundra surface remains frozen all year. This permanently frozen ground is called permafrost. Each summer, when the sun warms the tundra surface, the top few inches of soil thaw. This melted part is called the active layer.
The correct answer is option B, that is, Genetic drift greatly affects small populations, but large populations can recover.
Genetic drift in combination with mutation, natural selection, and migration is one of the most fundamental mechanisms of evolution. Genetic drift refers to a change in the relative frequency of distinct genotypes in a small populace, owing to the chance vanishing of specific genes as individuals do not reproduce or die.
The correct option is D.
If water density at freezing point is greater, the ice formed will sink to the bottom of the water body and freeze the water up from the bottom. This will surely lead to the death of everything that live inside the water.
