The correct answer is D.) The sun
The sun’s heat causes liquids to evaporate into water vapor, which rises and forms clouds. The whole water cycle repeats itself again because of the sun.
        
             
        
        
        
Answer:
N = 187.55
Explanation:
Here you just need to replace the terms and clear the equation.
You already know that,
- First capture: 25 prairie dogs.
- First marked animals: 25 (the whole first capture)
You let these animals leave and then you made another capture.
- Second capture: 135 prairie dogs
- Already Marked animals: 18 (these 18 dogs were caught in the first capture and marked before releasing them)  
To know the size of the prairie dogs population you just need to use the following equation and clear N, which is the value that you are looking for.  
Number of individual marked in first catch/Total population size, N = Number of individual marked in 2nd catch / Total number of 2nd catch
- Number of individual marked in first catch = 25 dogs
- Total population size, N = this is what we want to know
- Number of individual marked in 2nd catch = 18 dogs
- Total number of 2nd catch = 135 dogs
So now, we need to replace terms
25 / N = 18 / 135
25 / N = 0.1333
N = 25 / 0.1333
N = 187.55
 
        
             
        
        
        
Answer:
A. Neurotransmitters can act as ligands.
B. Acetylcholine is a neurotransmitter. It can bind to an acetylcholine receptor on the surface of a cell. If this receptor is also a sodium channel, we would call acteylcholine a ligand and its receptor a ligand gated receptor.
Explanation: 
Answer:
A. Neurotransmitters can act as ligands.
B. Acetylcholine is a neurotransmitter. It can bind to an acetylcholine receptor on the surface of a cell. If this receptor is also a sodium channel, we would call acteylcholine a ligand and its receptor a ligand gated receptor.
Explanation:
Neurotransmitter are chemicals that transfer signals between neurons and nerve cells. They control some physical and physiologocal activity such as appetite, food. 
Acetycoline is an example of neurotransmitter and it is located in the parasympathetic nervous system. Ligand are substance that form complexes with biomolecule. They serve biological purpose with this biomolecule. 
 This ligand binds to target site. Neurotransmitter act as ligand by binding to receptor in the postsynaptic neuron and acetycoline a type of neurotransmitter can also serve as ligand they bind to acetycoline receptor on cell surface.
 
        
             
        
        
        
Saprophytes are fungi that are capable of getting nourishment from decaying plants in order to live their lives longer. They are known to stay in rich soil and in various dead trees. They often reside in decaying wood as well.
        
                    
             
        
        
        
Answer:
The answer is nuclear fusion 
Explanation:
Solar energy is created by nuclear fusion that takes place in the sun. Fusion occurs when protons of hydrogen atoms violently collide in the sun's core and fuse to create a helium atom.