Answer:
The reflex arc follows this sequence of events
1. sensory receptor activation
2. sensory neuron activation
3.information processing
4. motor neuron activation
5. effector response
Explanation:
Reflex arc is the pathway of nerves during a reflex action. An example of a reflex arc is when we accidentally touch a hot object. First, the receptor in the skin detects a stimulus in this case the change in temperature. Second, the sensory neuron transmit the electrical impulses to the Central Nervous System for information processing. Then relay neurons connect sensory neurons to motor neurons. Third, motor neurons sends electrical impulses to an effector wherein the effector produces a response ( muscle contracts to move the hand away from the hot object. This happens in a split of seconds.
Continental drift happened around the Jurassic period, 175 million years ago.
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This is an example of negative feedback.
After a big meal, glucose levels in the bloodstream increases. The body recognises this change and goes through homeostasis, or the regulation of bodily state or internal environment.
The pancreas secretes insulin, which then binds to insulin receptors. This will result in the uptake of excess glucose from the bloodstream into cells and converted into glycogen to be stored in cells as energy storage molecules.
Since there is the counter effect of body (i.e. when blood-glucose concentration increases, the body sends a signal to decrease the blood-glucose concentration, this is called a negative feedback (instead of a positive feedback, which occurs if for e.g. the body signals cells to increase blood-glucose concentration even after blood-glucose concentration increased after a heavy meal).
Hope this helps! :)
Answer:
The correct answer is- Immune system
Explanation:
There are physical, chemical and immunological barriers present in our body which helps us to protect from the foreign antigen. They all assist each other and helps in pathogen removal from our body.
The physical barrier includes skin, gastrointestinal tract, respiratory tract, etc which do not allow the microbe to enter the body. Chemical barriers include tear, saliva, acid in the stomach which kills microbes on the body surface.
Immune cells like macrophages, B cells kills microbes when it gets in the body. Lymphatic system also contain immune cells and helps in microbe removal.
So the immune system is assisted by physical barrier, chemical barrier, and lymphatic system.
The ocean moderates the Earth's climate. Most solar radiation occurs at the Equator, whereas the poles receive little radiation. The ocean<span> transport warm water from the Equator toward the poles and cold water from the poles back to the Equator. The oceans provide a habitat for much of the marine life exploited by humans, such as harvested fish. The oceans act as a massive carbon sink, as phytoplankton absorb carbon from the atmosphere through photosynthesis. The ocean also provides a medium for large scale transportation of goods through shipping. It is unlikely that vehicles as large as container ships could ever be transported over land.</span>
