Answer:
The nucleus is an organelle found in most eukaryotic cells, the exception being red blood cells. ... 
The primary functions of the nucleus are to store the cell's DNA, maintain its integrity, and facilitate its transcription and replication.
 
        
             
        
        
        
Answer:
b. by increasing the heart rate
c. by increasing the respiratory rate
Explanation:
Increased activity of skeletal muscles would require an increased supply of oxygen to these cells to sustain the muscle contraction. Muscle cells perform aerobic cellular respiration in the presence of oxygen and produce ATP molecules to be used during muscle contraction. Therefore, there is an increase in heart rate to pump sufficient blood to the skeletal muscles which in turn ensures enough supply of oxygen. Also, there will be an increase in the respiration rate to inhale the required oxygen.
 
        
             
        
        
        
Answer:
0.062 moles of hydrogen gas
Explanation:
We must first out down the reaction equation before we can attempt to solve the problem.
Mg(s) + 2HCl(aq) ----> MgCl2(aq) + H2(g)
Next we obtain the number of moles in 1.5 g of magnesium metal from;
Molar mass of magnesium = 24.3 gmol-1
Number of moles of magnesium= mass/molar mass = 1.5g/24.3gmol-1 = 0.062 moles
From the reaction equation;
1 mole of magnesium metal yields 1 mole of hydrogen gas
0.062 moles of magnesium metal will yield 0.062 moles of hydrogen gas
Therefore, reaction of 1.5g of magnesium metal with excess hydrochloric acid will yield 0.062 moles of hydrogen gas.
 
        
             
        
        
        
Correct option is A)
There are electrical and concentration gradients in neurons that induce the sodium ions to enter the cell. The resting potential is maintained because the channels for sodium ions are closed. The membrane remains impermeable to sodium ions in the rest state. The membrane is more permeable to potassium passage. The potassium ions leak through the membrane at a greater rate than sodium enters. There is loss of positively charged ions from the inner part of the cell membrane. The inner part of the membrane carries a relatively more negative charge than the outer part of the cell membrane. 
Thus, the correct answer is option A. 
 
        
                    
             
        
        
        
Typically higher than a clear night