Question

1. Explain why unlike negative feedback, positive feedback is not a common feature of hormone pathways that help to maintain homeostasis glands origin and function? Ca2+ level near the set point? individual and an individual with diabetes mellitus 2. Explain how iodine affects the functioning of the thyroid 3. How do the two fused glands of the pituitary gland differ in 4. How does calcitonin and parathyroid hormones maintain 5. Explain the control of blood glucose in both a healthy Chapter 39 Plant hormones 1. Compare and contrast the actions of auxins, gibberellins and abscisic acid as plant hormones

Answer 1

Ans 1. Homeostasis is a process to maintain stability within an organism In response to environmental changes. It is the state of equilibrium condition within a body.

As the hormones release into the blood is controlled by a stimulus. It is either positive or negative, called positive feedback or negative feedback.

In positive feedback the effector response causes increase in stimulus, that lead to an even greater response.

Negative feedback occurs when the effector response to a stimulus reduces lead to response cease.

Thus,negative feedback are common features of hormone pathways than positive feedback that help to maintain homeostasis. Because negative feedback acts to reverse the direction of change. It ceases the response, as the variable being controlled reaches the set point. This leads to keep things constant.