6) Determine whether each of the following scenarios are part of the First, Second, or Third line of defense: (4) SCENARIO
LINE OF DEFENSE

Macrophages move through tissues and destroy any pathogens that they encounter.
First line of defense
Bacteria are destroyed by hydrochloric acid in the stomach after being ingested.

A phagocytic leukocyte digests a pathogen and presents the respective antigens on the surface of its membrane.

Antibodies in the bloodstream slow down a pathogen that has previously been encountered by white blood cells and mark it for destruction.

T-cells analyze pathogens after they have been broken down and recruit B-cells to help identify the foreign particles.

The answer would be sand and gravel

When you are making a guess you are forming a hypothesis

Hunting in the darksome fish rely on senses beyond sight. in the darkness of the marianas trench, a fish called the rattail has an extremely sensitive sense of smell. the fish uses scent, rather than sight, to steer toward food. once it's near food, the rattail uses a special organ on the bottom of its chin to guide itself by feel.marine snowone staple of the deep sea diet is "marine snow," flakes of organic, edible substances that sink down from the upper ocean. animals at the ocean's bottom find sustenance in everything from the bodies of dead creatures to fecal matter. marine snow is diverse enough to support numerous species. for instance, several species of snails and worms feed exclusively on deceased whales.microorganismsthe deep sea is an intricate ecosystem, and even the ocean floor itself plays a part. hydrothermal vents are cracks in the sea floor where erupting magma mixes with ocean water to produce plumes of hot, sulfur-rich chemicals. some microbes can use these chemicals for energy, sustaining their existence and that of the animals who depend on their roles in the deep sea food chain.