Answer:
A major obstacle life would have to overcome is having only a limited amount of natural light and then the rest of the time is darkness.
Human activity can affect the river ecosystems because first of all humans take the water and use it for themselves, they also pollute it, disturb the ecosystems and kill fish or oysters etc. in the ecosystems.
50/50
you see, the coin only has 2 sides
Also, you're flipping it twice
therefore, the probability is matched up and you have a 50/50 chance of getting heads at least 1 of those 2 times
(Hope it helped ^_^)
The action potential spreads through an axon by depolarizing adjacent membrane to threshold.
- K+ departs the cell after Na+, which enters the cell first. Ions can move freely across the axon membrane because of the difference during the action potential.
- Because sodium contains a positive charge, the neuron becomes more positive and depolarized. Potassium channels take longer to open. As soon as the cell does open, K+ rushes out, reversing the depolarization known as repolarization.
- Sodium channels close during the peak of the action potential when potassium leaves the cell. When potassium ions are effluxed, the membrane potential is lowered or the cell becomes hyperpolarized.
- Outside of the cell, the concentration of Na+ is greater than inside the cell. while the concentration of K+ is is greater inside the cell than outside.
learn more about action potential here: brainly.com/question/6705448
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Answer:
There are approximately five main climate types on Earth:
Tropical.
Dry.
Temperate.
Continental.
Polar.