Table of Contents
Secretion, Mechanism of Action, and Functions of Hormones
Hormones are secreted by endocrine glands and are carried by the blood to other parts of the body. There, they bind to specific receptors on the cells and cause changes in cell function. Hormones are essential for normal body function.
The thyroid gland secretes the hormone thyroxine, which is essential for normal growth and development. Thyroxine regulates the body’s metabolic rate and affects almost every organ in the body.
The adrenal gland secretes the hormones adrenaline and cortisol. Adrenaline is responsible for the “fight or flight” response, while cortisol helps to regulate the body’s metabolism and immune system.
The pancreas secretes the hormone insulin, which is responsible for regulating blood sugar levels.
The ovaries secrete the hormones estrogen and progesterone. Estrogen is responsible for the development of female sex characteristics, while progesterone is responsible for the maintenance of a pregnancy.
Types of Hormones
There are five types of hormones:
1. Peptide hormones
2. Steroid hormones
3. Amino acid derivatives
4. Protein hormones
5. Eicosanoids
1. Peptide hormones: Peptide hormones are short chains of amino acids. The body produces peptide hormones such as insulin, glucagon, and oxytocin.
2. Steroid hormones: Steroid hormones are produced by the body’s outer layer of cells, the adrenal cortex. Steroid hormones include cortisol, aldosterone, and sex hormones such as testosterone and estrogen.
3. Amino acid derivatives: Some hormones are derived from amino acids, the building blocks of proteins. These include thyroid hormones and adrenaline.
4. Protein hormones: Protein hormones are produced by specialized cells in various parts of the body. These include growth hormone, prolactin, and insulin.
5. Eicosanoids: Eicosanoids are hormones that are derived from fatty acids. These include prostaglandins and leukotrienes.
What Is The Mechanism of Hormone Action?
The hormone receptors are located on the cell surface. The hormone binds to the receptor and this initiates a series of events inside the cell that leads to a change in the cell’s activity.
What Is The Mechanism of Peptide Hormone Action?
Peptide hormones are water soluble molecules that are secreted by endocrine cells into the bloodstream. They are transported to their target cells, where they attach to receptors on the surface of the cells. The hormone-receptor complex then activates specific genes in the cell, which leads to the production of proteins that carry out the desired hormonal effect.
Hormonal Imbalance in the Human Body
Hormones are chemical messengers in the body that play a major role in controlling many important body functions. Hormonal imbalance can refer to an overproduction or underproduction of hormones. This can cause a variety of problems in the body, including infertility, weight gain, and mood swings.
Some common hormones that can become imbalanced include estrogen, progesterone, testosterone, and thyroid hormones. Often, hormonal imbalance can be caused by lifestyle factors, such as stress, poor diet, and lack of exercise. Other causes can include genetics, certain medical conditions, and medications.
If you are experiencing symptoms of a hormonal imbalance, it is important to consult with a healthcare provider. He or she can help identify the cause of the imbalance and recommend appropriate treatment.
Endocrine Glands and the Hormones Secretion
The endocrine glands are a group of organs that secrete hormones. The hormones are chemicals that circulate in the blood and control the activity of cells and organs. The hormones are secreted by the endocrine glands in response to signals from the brain or from other organs.
The hypothalamus is a part of the brain that controls the secretion of hormones by the pituitary gland. The pituitary gland is located below the hypothalamus and is the largest endocrine gland in the body. The pituitary gland secretes six hormones:
1. Adrenocorticotropic hormone (ACTH)
2. Growth hormone (GH)
3. Luteinizing hormone (LH)
4. Melanocyte-stimulating hormone (MSH)
5. Prolactin (PRL)
6. Thyroid-stimulating hormone (TSH)
The adrenal glands are located on top of the kidneys. The adrenal glands secrete two hormones:
1. Adrenaline (epinephrine)
2. Cortisol
The pancreas is located behind the stomach. The pancreas secretes two hormones:
1. Insulin
2. Glucagon
The ovaries are located in the female pelvis. The ovaries secrete one hormone:
1. Estrogen
Feedback Mechanism – Thyroid Hormone
The thyroid gland is a small, butterfly-shaped gland located in the lower part of the neck. The thyroid gland produces thyroid hormones, which are important for the body’s metabolism. The thyroid gland is controlled by the pituitary gland, which is located at the base of the brain. The pituitary gland produces a hormone called thyroid-stimulating hormone (TSH), which controls the production of thyroid hormones by the thyroid gland.
The hypothalamus, a small area of the brain, also controls the production of TSH by the pituitary gland. The hypothalamus produces a hormone called thyrotropin-releasing hormone (TRH), which controls the production of TSH by the pituitary gland.
The thyroid hormones influence the body’s metabolism, which is the process that produces the energy needed for the body to function. The thyroid hormones also help to control the body’s heart rate, breathing rate, and body temperature.
Solved Examples
Question 1:
The following table gives the number of passengers carried by a bus in each of five consecutive months.
Month Passengers January 95 February 105 March 110 April 120 May 125
Draw a graph to represent the data.
The graph is a line graph with the y-axis representing the number of passengers and the x-axis representing the months. The graph starts at 95 passengers in January and ends at 125 passengers in May.
Functions of Hormones
The role of hormones is to regulate and control the body’s activities. This is done by sending chemical messengers from one organ to another. Hormones help to maintain a balance in the body by controlling the rate at which different activities occur.
Fun Facts on About The Hormone Action In The Human Body
1. The hypothalamus is responsible for releasing gonadotropin-releasing hormone (GnRH), which stimulates the pituitary gland to produce the hormones luteinizing hormone (LH) and follicle-stimulating hormone (FSH).
2. LH and FSH stimulate the production of the sex hormones estrogen and testosterone in the ovaries and testes.
3. Estrogen and testosterone are responsible for the development and maintenance of the reproductive system and other secondary sex characteristics.
4. Estrogen also plays a role in the regulation of the menstrual cycle and the onset of menopause.
5. Testosterone is responsible for the development and maintenance of male sex characteristics, including the prostate gland and penis.
