Endocrine System Quiz

<p>Epinephrine (A)</p> Signup and view all the answers

<p>Amino acids (D)</p> Signup and view all the answers

<p>Tyrosine (C)</p> Signup and view all the answers

<p>Iodination (B)</p> Signup and view all the answers

<p>Bound to plasma proteins (C)</p> Signup and view all the answers

<p>Synthesized and stored in preformed vesicles. (A)</p> Signup and view all the answers

<p>They are degraded by stomach acid. (A)</p> Signup and view all the answers

<p>Steroid hormones (D)</p> Signup and view all the answers

<p>Buffering acute changes in hormone secretion. (A)</p> Signup and view all the answers

<p>It slows their clearance from plasma. (C)</p> Signup and view all the answers

<p>10^-12 to 10^-9 M (D)</p> Signup and view all the answers

<p>The cell will not respond to the hormone. (C)</p> Signup and view all the answers

<p>Downregulation of receptors (B)</p> Signup and view all the answers

<p>Downregulation (B)</p> Signup and view all the answers

<p>The response is affected more by the receptor affinity than the receptor number. (D)</p> Signup and view all the answers

<p>On the cell membrane, in the cytoplasm or the nucleus. (B)</p> Signup and view all the answers

<p>They serve as negative feedback signals. (A)</p> Signup and view all the answers

<p>The cell would have a reduced response to the same dose of insulin. (C)</p> Signup and view all the answers

<p>They are relatively polar molecules. (B)</p> Signup and view all the answers

<p>Cholesterol (B)</p> Signup and view all the answers

<p>They bind to carrier proteins, which extends their half-life. (D)</p> Signup and view all the answers

<p>Genomic effects which regulate protein synthesis (B)</p> Signup and view all the answers

<p>They are synthesized on demand and immediately diffuse out of the cell. (B)</p> Signup and view all the answers

<p>Peptide hormones are synthesized as preprohormones, while steroid hormones are synthesized from cholesterol. (D)</p> Signup and view all the answers

<p>Lipophilicity and the ability to be absorbed in the gastrointestinal tract. (C)</p> Signup and view all the answers

<p>Aromatase (A)</p> Signup and view all the answers

<p>To compete for the same receptor (B)</p> Signup and view all the answers

<p>Glucagon and growth hormone (B)</p> Signup and view all the answers

<p>Biological processes that occur about a day (C)</p> Signup and view all the answers

<p>Circadian rhythms (C)</p> Signup and view all the answers

<p>Jet lag (C)</p> Signup and view all the answers

<p>Secretion varies from minutes to months (C)</p> Signup and view all the answers

<p>Disturbs circadian clocks (A)</p> Signup and view all the answers

<p>Lightheadedness (D)</p> Signup and view all the answers

<p>To regulate the release of hormones from the pituitary gland (B)</p> Signup and view all the answers

<p>The production of excessive hormones (A)</p> Signup and view all the answers

<p>High levels of cortisol and low ACTH (A)</p> Signup and view all the answers

<p>Permissiveness (A)</p> Signup and view all the answers

<p>Adrenocorticotropic hormone (ACTH) (A)</p> Signup and view all the answers

<p>High ACTH and cortisol levels (D)</p> Signup and view all the answers

<p>Negative feedback to decrease CRH and ACTH (C)</p> Signup and view all the answers

<p>Cortisol (C)</p> Signup and view all the answers

<p>Increased cortisol levels (A)</p> Signup and view all the answers

<p>Neutralizes the action of another hormone (D)</p> Signup and view all the answers

<p>Reproductive hormones are ineffective without TH (D)</p> Signup and view all the answers

<p>Primary hyposecretion due to adrenal failure (C)</p> Signup and view all the answers

<p>High levels of CRH and ACTH, leading to excess cortisol (B)</p> Signup and view all the answers

A specialized signaling molecule released from a cell or group of cells into the bloodstream. Hormones act on distant target tissues, triggering physiological responses even at low concentrations.

Glands are organs that produce and secrete substances, including hormones, into the body. Endocrine glands specifically release hormones directly into the bloodstream.

The endocrine system is a network of glands that produce hormones. These hormones regulate various body functions, such as metabolism, growth, and reproduction.

Hormones are classified based on their chemical structure:

• Peptide/Protein Hormones: Chains of amino acids, like insulin and growth hormone.
• Amine Hormones: Derived from amino acids, like adrenaline (epinephrine) and thyroid hormones.
• Steroid Hormones: Derived from cholesterol, like testosterone and cortisol.

Hormones exert their effects by binding to specific receptors on target cells. This binding initiates a series of signaling events that trigger a cellular response.

Hormones derived from cholesterol, lipid-soluble, synthesized on demand, diffuse out of parent cell's smooth endoplasmic reticulum, bind carrier proteins in blood, have cytoplasmic or nuclear receptors (genomic effect) and cell membrane receptors (nongenomic response).

Synthesized in the smooth endoplasmic reticulum of the cell, they are lipid-soluble and can easily cross cell membranes.

A type of receptor found in the cytoplasm or nucleus of cells that binds to steroid hormones, triggering a change in gene expression and protein synthesis.

The direct effect of a steroid hormone on gene expression, leading to protein synthesis, a slower but longer lasting action.

The rapid, non-genomic effect of a steroid hormone, triggered by its binding to cell membrane receptors, leading to quick changes in cell function.

Proteins or peptides that are synthesized as precursors, stored in vesicles, are polar, circulate unbound in blood, cannot be administered orally, and have cell membrane receptors.

Proteins produced in the body that act as chemical messengers, affecting the function of target cells and organs.

Transport proteins that bind to steroid hormones in the blood, increasing their half-life and ensuring their delivery to target cells.

The ability of a receptor to bind to a specific hormone and initiate a biological response. This binding is highly selective, meaning that each receptor typically only binds to one specific type of hormone.

A process where the number of receptors on a target cell increases, making the cell more sensitive to the hormone.

A process where the number of receptors on a target cell decreases, making the cell less sensitive to the hormone.

A mechanism where the hormone-receptor complex is engulfed by the cell membrane and taken inside the cell. This is a key process in receptor downregulation.

The amount of hormone required to produce a response. Often described as the concentration of hormone required to reach 50% of the maximum response.

The concentration of hormone in the blood, which can vary depending on the hormone and the individual's physiological state. This is often expressed in molar units (mol/liter).

The ability of a cell to respond to a hormone. It can be influenced by factors such as the number of receptors and the affinity of the receptors for the hormone.

The ability of a cell to take up and use glucose effectively. It is directly related to insulin responsiveness. When insulin sensitivity is impaired, cells are less able to take up glucose, leading to elevated blood sugar levels.

Two hormones that affect the same target tissue but with opposing effects, often using different mechanisms to achieve their goals.

A type of regulation where two or more hormones interact in a way that their combined effect is greater than the sum of their individual effects.

Internally generated rhythms that persist even in the absence of external time cues such as light or dark.

Biological clocks that operate on a daily cycle (about 24 hours) regulating various physiological processes like sleep-wake cycles and hormone secretion.

Rhythmic fluctuations in hormone secretion that occur over different time periods, ranging from minutes to months.

The disruption of the body's natural circadian rhythm due to rapid travel across multiple time zones.

Conditions like fatigue, difficulty concentrating, and sleep disturbances that arise from disruption of the body's internal biological rhythm due to factors like shift work, space travel, or jet lag.

The ability of the body to adapt and adjust its internal processes to match changes in the external environment.

Catecholamines are a group of hormones derived from tyrosine and include dopamine, norepinephrine, and epinephrine. They are synthesized within endocrine cells and stored in vesicles. Catecholamines are water-soluble and can be transported freely in the blood, as well as bound to plasma proteins.

Thyroid hormones are synthesized from tyrosine and iodine. They are stored in the thyroid follicle and are not water-soluble, transported bound to plasma proteins. Thyroid hormones are administered orally and act through intracellular receptors.

Hormones that are derived from the amino acid tyrosine. They are divided into two groups: catecholamines and thyroid hormones.

Hormones, like steroid or thyroid hormones, rely on proteins in the plasma for transport. These proteins bind to the hormone reversibly, and the binding is saturable, meaning a limit exists for how much hormone can be bound at a time.

Hormones bind to plasma proteins to facilitate their transport throughout the body. This binding acts as a 'reservoir,' buffering acute changes in hormone secretion. It also slows down the clearance of hormones from the plasma.

Hormone-protein binding is a reversible reaction where a hormone binds to a protein in the plasma. This binding can be represented as: [hormone] + [protein] <-> [hormone-protein complex]. It's crucial to note that the free hormone, not bound to protein, is the biologically active form.

Hormones exert their effects by binding to their specific receptors. The interaction between a hormone and its receptor triggers a series of events leading to a cellular response. The type of response depends on the hormone, receptor, and target cell.

The determinants of hormone response are diverse and include factors like: hormone concentration, receptor affinity, number of receptors, presence of co-factors, post-receptor signaling pathways, and the target cell's physiological state.

A negative feedback loop where the hormone produced by the target gland (e.g., cortisol) inhibits the release of the trophic hormone from the anterior pituitary gland. This helps to maintain homeostasis by preventing excessive hormone production.

A negative feedback loop where the trophic hormone (e.g., ACTH) produced by the anterior pituitary gland inhibits the release of the releasing hormone from the hypothalamus. This helps to fine-tune hormone production.

Located in the brain, it secretes releasing hormones that stimulate the anterior pituitary gland to release trophic hormones.

A hormone that stimulates the release of another hormone. Often secreted by the anterior pituitary gland.

It releases trophic hormones that target other endocrine glands to produce their specific hormones. An example is the release of ACTH from the anterior pituitary.

The organ or cell that responds to a hormone and undergoes a change. Example - muscle cell.

Secretion of excessive amounts of hormones, leading to hyperactivity of target tissue.

Secretion of insufficient amounts of hormones, leading to hypoactivity of target tissue.

Excessive cortisol production due to a problem with the adrenal cortex, the target gland.

Excessive cortisol production due to a problem with the anterior pituitary gland, the source of ACTH trophic hormone.

Excessive cortisol production due to a problem with the hypothalamus, the source of CRH releasing hormone.

The combined effect of two hormones working together is greater than the sum of their individual effects.

One hormone is required for another hormone to exert its full effect.

One hormone opposes the action of another hormone.