These receptors can be present on a specific type of cell, a specific type of tissue or a specific type of organ. … Key Points. • Hormones have specific receptors on the target cells, tissues or organs that detect them and the hormones can show their effect.
What is specificity in the endocrine system?
Hormones are chemicals within the endocrine system that affect physiological activity. They are secreted by one tissue and conveyed by the bloodstream to another tissue. Hormones have high levels of specificity, which means they only react with certain receptor sites in the body.
How do hormones achieve specificity?
The hydrophobic hormones bind to intracellular receptors and only those cells with the appropriate intracellular receptors can respond. Specificity of hormone action derives from the specificity of the molecular interaction of hormone and receptor.
Why is it that some hormones are very specific as to which cells they affect and other hormones have a very general effect on many target organs?
However, a given hormone usually affects only a limited number of cells, which are called target cells. A target cell responds to a hormone because it bears receptors for the hormone. … In very basic terms, binding of hormone to receptor triggers a cascade of reactions within the cell that affects function.
What is meant by target cell specificity?
– Relative number of receptors on the target cell – The affinity of those receptors for the hormone. Up-regulation. target cells form more receptors in response to the hormone. Down-regulation.
Which is faster the endocrine system or the nervous system?
The signal transmission of the nervous system is fast because neurons are interconnected, but the functions are more short-lived. Signal transmission in the endocrine system is slow, since hormones must travel through the bloodstream, but the responses tend to last longer.
Which type of hormones can enter cells?
Lipid-derived (soluble) hormones can enter the cell by diffusing across the plasma membrane and binding to DNA to regulate gene transcription and to change the cell’s activities by inducing production of proteins that affect, in general, the long-term structure and function of the cell.
What are the 3 major hormone groups?
There are three basic types of hormones: lipid-derived, amino acid-derived, and peptide.
What are the 2 main types of hormones?
Types of hormones
- Protein hormones (or polypeptide hormones) are made of chains of amino acids. An example is ADH (antidiuretic hormone) which decreases blood pressure.
- Steroid hormones are derived from lipids. …
- Amine hormones are derived from amino acids.
Which hormone is known as local hormone?
Local hormones are produced by nerve and gland cells and bind to either neighboring cells or the same type of cell that produced them. … Eicosanoids (ī′kō-să-noydz; eicosa = twenty, eidos = formed) are a primary type of local hormone.
What do all hormones have in common?
The correct answer: The character that all hormones have in common is (c) They bind to and interact with a receptor in the target cell.
What hormone has the most target cells?
Almost all body cells are targets of thyroid hormones. Thyroid hormone increases the overall metabolic rate, regulates growth and development as well as the onset of sexual maturity.
How many steroid hormones are there?
More than 30 steroids are produced in the adrenal cortex; they can be divided into three functional categories: mineralocorticoids, glucocorticoids, and androgens.
What is an example of a paracrine hormone?
Excellent examples of the paracrine actions of hormones are provided by the ovaries and testes. Estrogens produced in the ovaries are crucial for the maturation of ovarian follicles before ovulation. Similarly, testosterone produced by the Leydig cells of the testes acts on adjacent…
What are the four factors that determine the plasma hormone concentration?
Factors affecting the concentration of a hormone in the blood
- rate of release of the hormone by the endocrine gland.
- rate of excretion by the kidneys.
- rate of inactivation by the liver.
What are the factors that can influence target cell response?
Target cell activation is dependent on three factors:
- The levels of hormone in the blood.
- The relative number of hormone receptors on the target cell.
- The hormone–receptor affinity.