<span>The juxtaglomerular apparatus is a structure (formed by the distal convoluted tubule and the glomerular afferent arteriole) with the function in the regulation of blood pressure and the filtration rate of the glomerulus. Its primary components are:
</span> <span><span>· </span>the macula densa- specialized epithelial cells in the distal convoluted tubule (detect Na concentration),
</span> <span><span>· </span>juxtaglomerular cells- formed from the smooth muscle cells of the afferent arteriole (secrete renin),</span>
<span><span>· </span>extraglomerular mesangial cells (lacis cells)-unknown function.</span> <span> </span>
A ribosome is a cell organelle. the function of a ribosome is like a micro-machine for making proteins. the ribosomes is composed of special proteins and nucleic acid. it is also formed from two sub units, locking together its function are to translate the encoded information from the cell nucleus provied by the messenger.
Answer:
The correct answer is: (A).
Explanation:
- In the question, it is mentioned that the algae can grow under the conditions of "enough sunlight" and "enough nutrients".
- Sunlight reaches the algae, by first falling on the surface made up of ice and snow and then refracting from there into the top layer of the ice where the algae grows.
- However, the capability of both snow and ice to reflect sunlight is far more than that of refracting sunlight.
- Therefore, the amount of light received by the algae is similar in absence or presence of the layer of snow on the top layer of ice.
- However, on deposition of snow on the layer of the ice, the weight of the ice increases and it sinks below into sea water.
- This allows more nutrient rich sea water to percolate into the ice and reach the algae.
- The algae receive more nutrients from the sea water and hence is capable undergoing better metabolism and growth.
- Hence, more algae are produced under such a situation.