Hormones: Peptide, Protein, and Steroid Classes

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Questions and Answers

Which hormone is secreted by the pancreas to lower blood glucose levels?

Adrenaline

Glucagon

Insulin (correct)

Oestrogen

The release of hormones from the pituitary gland is always triggered by the nervous system.

False

What is the primary function of hormones released by the pituitary gland?

To regulate the release of other hormones

The hormone _____ released from the hypothalamus stimulates the pituitary gland to release follicle-stimulating hormone (FSH).

GnRH Signup and view all the answers

Match each type of hormone with its characteristic:

Steroid Hormones = Trigger gene activity and have a slower response Peptide Hormones = Act quickly and often involve enzyme activation Insulin = Lowers blood glucose levels Glucagon = Raises blood glucose levels Signup and view all the answers

Which hormone is known for raising blood sugar levels?

Glucagon Signup and view all the answers

Steroid hormones are both hydrophilic and lipid soluble.

False Signup and view all the answers

Name one function of insulin in the body.

Lowers blood sugar levels Signup and view all the answers

Hydrophilic hormones bind to __________ on the surface of target cells.

receptors Signup and view all the answers

Match the hormones with their primary functions:

Insulin = Lowers blood sugar Thyroxine = Increases metabolism Testosterone = Development of male reproductive system Glucagon = Raises blood sugar Signup and view all the answers

Which type of hormone usually produces fast responses in target cells?

Peptide hormones Signup and view all the answers

Non-steroid hormones can diffuse directly through the cell membrane.

False Signup and view all the answers

What is one characteristic of steroid hormones in relation to cell membranes?

They can freely diffuse across the cell membrane. Signup and view all the answers

The __________ hormone complex enters the nucleus to initiate transcription of specific genes.

receptor Signup and view all the answers

What type of hormone is made from cholesterol?

Steroid Signup and view all the answers

Peptide hormones can easily pass through the phospholipid bilayer of the cell membrane.

False Signup and view all the answers

Name one example of a peptide hormone.

ADH Signup and view all the answers

FSH promotes the development of ______ in women.

eggs Signup and view all the answers

Match the hormone with its type:

ADH = Peptide Epinephrine = Protein Oestrogen = Steroid Human Growth Hormone = Protein Signup and view all the answers

How do steroid hormones primarily affect cells?

By forming a receptor-hormone complex that enters the nucleus Signup and view all the answers

Epinephrine is a steroid hormone that affects the cardiovascular system.

False Signup and view all the answers

What is the role of the pituitary gland in the endocrine system?

It releases hormones that regulate various bodily functions. Signup and view all the answers

Study Notes

Hormone Types and Structure

Hormones can be classified as peptides, proteins, or steroids based on their structural properties.
Peptides consist of short chains of amino acids (polypeptides).
Proteins are longer chains of amino acids, often derived from tyrosine.
Steroids are lipids derived from cholesterol and are lipid-soluble.

Hormone Mechanism of Action

Peptide and protein hormones, which are polar, cannot diffuse across cell membranes and instead bind to surface receptors.
Upon binding, they activate relay proteins inside the cell, initiating cascades that alter metabolism and gene expression.
Steroid hormones diffuse through the cell membrane due to their lipid solubility, binding to internal receptors in the cytoplasm or nucleus.
The receptor-hormone complex formed in steroid action enters the nucleus to affect transcription of specific genes.

Examples of Hormones

Peptide Hormones:
- ADH (Antidiuretic Hormone): Manages water levels; acts in kidneys.
- Insulin: Lowers blood sugar; produced in the pancreas.
- Glucagon: Raises blood sugar; also produced in the pancreas.
Protein Hormones:
- Epinephrine (Adrenaline): Produced in adrenal glands; involved in fight or flight response.
- Human Growth Hormone: Influences bone and muscle mass and decreases fat; secreted by anterior pituitary.
- Norepinephrine: Similar role to epinephrine, mainly acting on cardiovascular systems.
- FSH (Follicle-Stimulating Hormone): Promotes egg development in women and sperm in men; made in the anterior pituitary.
Steroid Hormones:
- Oestrogen: Develops secondary sexual characteristics in females; produced in ovaries.
- Testosterone: Promotes development of male reproductive system.

Hormone Release Mechanisms

Hormones can be released in response to signals from the nervous system or other hormones.
Example: Insulin release is triggered by the nervous system's signals to the pancreas.
Hypothalamus releases GnRH which stimulates the pituitary gland to release FSH, affecting ovarian hormone production.

Blood Glucose Regulation

Blood glucose levels are tightly regulated to stay within a tolerance range.
Specialized pancreatic cells detect deviations and secrete glucagon or insulin, which exert opposite effects on blood glucose levels.

Characteristics of Hormone Responses

Peptide hormones produce rapid, short-term responses due to their water solubility and receptor action.
Steroid hormones result in slower, long-term responses by altering gene expression through direct interaction with DNA.

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Description

Explore the different classes of hormones in this quiz, focusing on peptides, proteins, and steroids. Each type is defined by its unique structure and composition, with specific functions in the body. Test your knowledge on their characteristics and differences!