The liver acts to keep blood glucose at a relatively constant level. it takes up glucose from the blood when levels are too high, and adds glucose to the blood when levels are too low. are these actions of the liver an example of homeostasis? a. yes, because homeostasis involves the maintenance of constant internal conditions. b.yes, because homeostasis is the interaction between two separate organs or tissues, such as the liver and blood. c.no, because homeostasis involves only positive feedback, not feedback inhibition. d.no, because homeostasis involves only tissues and organs from the same organ system.

Ans.

Liver helps to keep the blood sugar in a constant level by different means. When blood sugar level increases, liver cells increase glucose uptake due to influence of insulin hormone and thus, decrease sugar level in blood. When sugar level decreases, liver cells show gluconeogenesis and add sugar into the blood due to the action of glucagon hormone, and thus, increase blood sugar level.

As homeostasis is a mechanism that involves maintenance of constant internal conditions, and liver shows maintenance of constant sugar level in body, the correct answer is 'option a).'

enzyme active site and substrate specificity

enzymes bind with chemical reactants called substrates. there may be one or more substrates for each type of enzyme, depending on the particular chemical reaction. in some reactions, a single-reactant substrate is broken down into multiple products