Question:
Which of the following statements correctly describe(s) the driving forces for diffusion of Na+ and K+ ions through their respective channels? Select all that apply.
A)The diffusion of Na+ ions into the cell is facilitated by the Na+ concentration gradient across the plasma membrane.
B)The diffusion of Na+ ions into the cell is impeded by the electrical gradient across the plasma membrane.
C)The diffusion of K+ ions out of the cell is impeded by the K+ concentration gradient across the plasma membrane.
D)The diffusion of K+ ions out of the cell is impeded by the electrical gradient across the plasma membrane. The electrochemical gradient is larger for Na+ than for K+.
Answer:
"The concentration gradient and the electro-chemical gradient" describes the driving forces for diffusion of Na+ and K+ ions through their respective channels
Explanation:
The Na ions diffusion inside the cell is facilitated by the concentration gradient of the Na ions which is present across the plasma membrane. Hence, the diffusion of the K ions which is present outside the cell and will be impeded due to the electrical gradient which is present near the plasma membrane. Thus, the electro-chemical gradient is greater as compared to the Na ion than that of the K ion.
Answer:
0.0055 mol of N2O5 will remay after 7 min.
Explanation:
The reaction follows a first-order.
Let the concentration of N2O5 after 7 min be y
Rate = Ky = change in concentration of N2O5/time
K is rate constant = 6.82×10^-3 s^-1
Initial concentration of N2O5 = number of moles/volume = 2.1×10^-2/1.8 = 0.0117 M
Change in concentration = 0.0117 - y
Time = 7 min = 7×60 = 420 s
6.82×10^-3y = 0.0117 - y/420
0.0117 - y = 420×6.82×10^-3y
0.0117 - y = 2.8644y
0.0117 = 2.8644y + y
0.0117 = 3.8644y
y = 0.0117/3.8644 = 0.00303 M
Number of moles of N2O5 left = y × volume = 0.00303 × 1.8 = 0.0055 mol (to 2 significant digits)
<h3><u>Answer;</u></h3>
<em>All the above</em>
Workers at construction sites often reduce erosion by;
- <em>Moving excess sediment back to its original location
</em>
- <em>Planting trees
</em>
- <em>Spraying water on bare soil</em>
<h3><u>Explanation;</u></h3>
- Soil erosion is a naturally occurring process which involves the wearing away of the topsoil by natural forces such as wind, water or other forces associated with farming.
- <em><u>Construction of roads and buildings results to large amounts of soil erosion around the world. It is therefore important to put measures that would help reduce soil erosion at construction sites</u></em>. These measures uses principals of soil control such as implementing sediment control, limiting soil exposure, reducing the runoff velocity, and modifying topography among others.
Answer:
The thumb alone is controlled by nine separate muscles; The hand has been used as a symbol of protection since ancient times; The human hand is different to the hands or paws of other animals, because it has fingers and a thumb that can work together. Each finger has 3 bones and the thumb has two bones
Explanation:
Answer:
They have the chance to inhale toxic fumes secreted by the mixture.
Explanation: