I think it’s erosion... not sure what you’re asking
Plants convert the sun's energy into carbohydrates via photosynthesis.
Answer:
The autonomic nervous system is the main neural regulator of circulation and blood pressure in the short term and beat by beat and exerts its function through various reflexes that regulate vasomotor tone, heart rate and cardiac output. At the renal level, the renin–angiotensin–aldosterone system is possibly the most important in the maintenance of arterial homeostasis.
Explanation:
Blood pressure is regulated by a series of interrelated autonomic systems and humoral reflexes, which continually adjust the determining elements of the system (heart rate, stroke volume, total peripheral resistance and circulating volume).The effective circulating volume is controlled by a series of reflex systems, which obtain information about the perfusion pressure (baroreceptors in the carotid bulb and aortic arch), plasma osmolarity (hypothalamus) and urinary sodium (distal tubule).The kidney has its own self-regulatory mechanisms. The reduction in renal blood flow is detected at the level of the mesangial cells of the juxtaglomerular apparatus, starting the renin-angiotensin system. The increase in angiotensin II produces on the one hand local vasoconstriction, and on the other hand stimulates the production of aldosterone by the adrenal cortex with the consequent tubular reabsorption of sodium and water.Antidiuretic hormone or vasopressin (released from the hypothalamus by stimulation of arterial baroreceptors and also by stimulation of angiotensin II) also acts at the renal level, which acts as a powerful and water-saving vasoconstrictor in the distal tubule.
The controlled experiments are performed by the scientists, when they want to study the changes in the sample on changing a single variable. So, the correct answer is option (b).
In case, all variables are kept same, no changes would be observed in the experiment sample. A controlled experiment can be performed on living thing as well as non living. But, controlled experiment cannot be performed on the things which are influenced by a lot of variables, as they cannot create realistic results. So, the option (a), (c), and (d) are incorrect.
A cell that just fertilized has to divide 6 times to form a 64 cell blastomere.
<u>Explanation:</u>
Human reproduction begins with the fusion of male gamete sperm and female gamete ovum. The fusion of sperm and ovum forms the zygote that is diploid. The zygote then undergoes mitotic division to develop into embryo.
The zygote first divides into two and the two individual cells divide again to form four individual cells and so on. Thus the number of cells after each division can be represented by the equation 
where n is the number of divisions. in the question it is given that the blastomere has 64 cells.
n=6
This means that the fertilized cell has to divide 6 times to develop into 64-celled blastomere.
