Hormones glucagon and insulin are produced in the alpha and beta cells respectively in the Islet of Langerhan in the pancreas. They are involved in the negative feedback system of blood glucose regulation in homeostasis.
GLUCAGON: when there is a low blood glucose concentration, the pancreas detect this and alpha cells produce and release glucagon. Glucagon causes the cells of the body to absorb less glucose from the blood. It also inhibits the process of converting glucose into glycogen (glycogenesis) and cause gluconeogenesis (process of converting amino acids/proteins and lipids/fats into glucose) and glycogenolysis (conversion of glycogen to glucose). Finally, glucagon decreases the rate of respiration so less glucose is required.
INSULIN: when blood glucose is high, insulin is released. Insulin binds with cell surface receptors of cells and activates the enzymes attached to the receptor. The enzymes cause a conformational change in the structural proteins that surround glucose transport protein containing vesicles, causing them to move out of the way so the vesicles migrate up to the cell membrane and glucose transport proteins can fuse with it. Thus, more glucose can be taken in by cells. Insulin also cause glycogenesis (converting glucose into glycogen) and inhibits gluconeogenesis and glycogenolysis.
Basically insulin decreases blood glucose concentration (eg. after eating) and glucagon increases it (eg. skipping breakfast in the morning)
Answer:
Because natural selection selects for it. Thus it persists.
Explanation:
You have to understand heterozygote advantage. Basically, it's where heterozygotes have an advantage over homozygotes. In the case of sickle cell disease, heterozygotes have an advantage, and natural selection favors whatever is advantageous. Thus, because heterozygotes each have one recessive sickle-cell allele, as natural selection favors the heterozygotes, the recessive sickle-cell allele persists and remains in the gene pool.
Answer: no it is not true
Explanation:
Answer:
Complete orbit around the Sun takes about 365.26 days. The Earth’s rotation axis is tilted relative to the imaginary space orbit around the Sun.  This imaginary plane is called the ecliptic plane.  Position of northern and southern hemisphere toward the Sun varies depending on the season
Explanation:
In cold climates, the amount of snow on the ground may decrease even if the temperature stays below zero degrees Celsius. The process that best explains <span>this event is B. sublimation. </span>
