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Describe how the structure of alveoli in the lungs enables efficient oxygen supply during aerobic respiration?

The alveoli are sac like structures which have a large surface area to volume ratio allowing for fast diffusion of oxygen into the blood (Fick's law). This large SA:V ratio is generated because the alveoli h...
PB
Answered by Philip B. • Biology tutor
7590 Views

How does the heart pump blood through the chambers of the heart to then send it round he body?

Firstly the heart is myogenic, thereofore is controlled by the autonomic nervous system hence doesnt require conscious control. The pumping mechanism of the heart begins with stimulation of the Sinoatrial no...
KB
7351 Views

How do I calculate the gradient of a linear (straight) graph?

To find the gradient of a straight line we can use the change in the X and Y directions. The gradient (Slope) of a straight line is defined as : ​Grad = (Change in Y) / (Change in X) This is the basis of a v...
NA
Answered by Nathan A. • Maths tutor
7578 Views

Describe and explain the trend in reactivity of the alkali metals (Group 1)

Reactivity increases down the group. The number of electron shells increases down the group. Therefore the outer electron is further away from the nucleus. Consequently, the attraction between the outer elec...
EJ
18729 Views

The price of a book is £4. In a sale the price is reduced by 30%. Work out the sale price.

The full price (100%) is £4The sale price is 30% less. So the sale price is 70% of the original price.£4 * 0.7 = £2.80
EJ
Answered by Elakkeya J. • Maths tutor
5660 Views