Answer:
The correct answer is- spirochetes
Explanation:
Spirochetes are a group of bacteria which are long, flexible and helical shaped. Some of them are associated with some disease in humans like yawns, lime disease, syphilis, etc.
Yawn is childhood infectious disease caused by a spirochete bacteria called Treponema pallidum pertenue. These bacterial usually affect the children who live in tropical regions like Africa, Southeast Asia. They can affect skin, bones, and joints. They can spread through direct contact with skin sores.
So the cells of T. pertenue which are helical, relatively long, and flexible known as spirochetes.
Thermocline - <span>a steep temperature gradient in a body of water, that is marked by a layer above and below at which the water is at different temperatures.
halocline - </span><span> a subtype of chemocline caused by a strong, vertical salinity gradient within a body of water.
pycnocline - </span><span>a layer in an ocean or other body of water in which water density increases rapidly with depth.</span>
To perform photosynthesis, plants need three things: carbon dioxide, water, and sunlight.
