一歩一歩学ぶ生命科学
POINT!

(Synthesis, secretion, and concentration in blood of) glucagon increases blood glucose. Before meal, glucagon has certain levels of synthesis, secretion, concentration in blood, and blood glucose-increasing effect.

① Subject had meal. Blood glucose is increased due to the meal. Glucagon (synthesis, secretion, and concentration in blood) increases blood glucose. These are in the same direction (red).



② Since these are in the same direction (red), negative feedback inhibits (blue) glucagon (synthesis, secretion, and concentration in blood). Because of this, the blood glucose-increasing effect of glucagon weakens, and the increase in blood glucose (red upward unfilled arrow) disappears (increased blood glucose decreases to the baseline).


Like, when room temperature is increased (summer), heater (function) is decreased, this is also redblue negative feedback.

Challenge Quiz

1.

Blood glucose is increased decreased due to the meal, glucagon (synthesis, secretion, and concentration in blood increases decreases blood glucose. Since these are in the same direction opposite direction , negative feedback inhibits facilitates glucagon. Because of this, the initial transition dissapears and the blood glucose increases decreases (towards the baseline).

2.

When blood glucose is increased, negative feedback facilitates inhibits glucagon (synthesis, secretion, and concentration in blood).