Answer:
Valves
Explanation:
Circulation is maintained in the veins by the valves.
Veins are part of the blood circulation system and blood vessels that transports deoxygenated blood from parts of the body back to the heart. Within the veins are valves (flap like structures) which maintain circulation by ensuring that blood in the veins move in the proper direction toward the heart. Blood that is being transported through the vein usually have low pressure. The valves work by providing pressure to enhance the blood’s movement, and they also disallow backflow of blood as it moves through the body. Most of the veins, especially the ones located in the legs and arms usually have one-way valves.
The rats was given to the student
in Humans, goosebumps is a reflex that helps with the fight-or-flight response, meaning in intense situations, we either run or fight back, depending on the situation. Since we humans evolved from being on all fours to standing upright, these goosebumps actually acted like a danger meter, protecting us from deadly predators or anything dangerous if we could.
Answer:
in the geosphere
Explanation:
The drill will eventually stop within the geosphere.
- The biosphere is the region of the earth populated by living organisms.
- The geosphere is the region of the earth made up of solid rock
- The atmosphere is the gaseous part of the earth.
- The hydrosphere is the liquid part of the earth or where water dominates the earth.
The drill pierces through the geosphere as it initially passes through the hydrosphere. Eventually, the drill stops within the geosphere.