Hormone feedback loops notes

What is a hormone feedback loop?

A regulatory mechanism where hormone levels control their own production, maintaining homeostasis.

True or false: Hormone feedback loops only involve negative feedback.

False, because they can involve both negative and positive feedback.

Difference between negative and positive feedback loops?

Negative feedback decreases output to stabilize, while positive feedback enhances output.

What triggers the release of insulin?

Increased blood glucose levels stimulate the pancreas to release insulin.

Fill in the blank: The hypothalamus regulates the pituitary gland via ___.

hormones that either stimulate or inhibit its secretion.

Which hormone lowers blood sugar?

Insulin lowers blood sugar by facilitating glucose uptake in cells.

What hormone increases blood sugar levels?

Glucagon increases blood sugar by stimulating glycogen breakdown in the liver.

True or false: Feedback loops are static and do not change.

False, because feedback loops can adapt to changing physiological conditions.

What is the role of oxytocin?

Oxytocin facilitates childbirth and lactation; it follows a positive feedback mechanism.

Compare the effects of cortisol and adrenaline.

Cortisol manages stress responses, while adrenaline prepares the body for immediate action.

What is the primary function of the thyroid hormone?

It regulates metabolism, energy production, and growth.

True or false: All hormones use feedback loops.

True, because feedback loops regulate hormone levels to maintain balance.

What is homeostasis?

The maintenance of a stable internal environment despite external changes.

Fill in the blank: The ______ axis regulates stress response involving the hypothalamus, pituitary, and adrenal glands.

HPA (Hypothalamic-Pituitary-Adrenal) axis.

Which feedback loop is primarily involved in blood calcium regulation?

Negative feedback loop involving parathyroid hormone and calcitonin.

What initiates positive feedback during childbirth?

Stretching of the cervix triggers oxytocin release, increasing contractions.

True or false: Hormone receptors can only bind one type of hormone.

False, because some receptors can bind multiple hormones with similar structures.