-
Define endocrine.
“Internal secretions”. This is undergone when the hormone is secreted into the blood stream.
-
Define paracrine.
The hormone effects the cell adjacent to the secreting cell.
-
Define autocrine.
The secreting cell is the same as the target cell. Note: If the hormone goes into the blood stream and recirculates back to the secreting cell, it is not considered autocrine, but endocrine.
-
The 1) _________________ consists of ducts, while the 2) ________________ is considered ductless.
- 1) exocrine system
- 2) endocrine system
-
Define hormone.
Chemical messenger produced by a ductless gland or tissue that effects a change in cellular activity of a target organ.
-
Define juxtacrine.
Hormone is secreted by a cell that is connected to the target cell.
-
Define intracrine.
The secreting cell secrtes the hormone within the same cell, which in turn binds an intracellular receptor.
-
Describe chronic hormone regulation and give an example.
This is usually done to maintain a certain state by a continued optimum secretions of hormone. An example would be parathyroid hormones.
-
Describe acute hormone regulation and give an example.
This is usually done sporadically and done in response to urgent situations to maintain homeostasis. An example is the release of epinephrine in response to stress.
-
Describe cyclic hormone regulation and give an example.
This is done periodically. Examples include the female reproductive hormones, progesterone and estrogen.
-
Describe synergism.
In this mechanism, when two chemical mediators/drug combine, they induce higher effects in a multiple manner. For example, 2+2=5.
-
Describe permissiveness.
In this mechanism a second hormone/drug is needed in order to facilitate the other.
-
Describe antagonism.
In this mechanism, when one hormone/drug is combined with another, it reduces the effectiveness of the second hormone/drug. For example 2+2=3.
-
Describe additive.
In this mechanism, when one hormone/drug is combined with another, the effects are increase normally. For example, 2+2=4.
-
Give two examples of hypersecretion.
- 1) Graves' disease
- 2) cancer
-
Give two examples of hyposecretion.
-
The prehormone consists of the 1) ______________________________________ and the prohormone consist of the 2) ______________________________________.
- 1) signal sequence and redundant sequence
- 2) redundant sequence
-
The signal sequence is detached from the pre-prohormone in the 1) __________ and the redundant sequence is detached from the prohormone in the 2) __________.
- 1) endoplasmic reticululm
- 2) vessicle
-
Define half-life.
The time the concentration decreases to half the original concentration.
-
The pharmacological amount is usually ______________ the physiological amount.
greater than
-
Describe the priming effect of hormones.
An upregulation occurs, inducing the increased producton of a hormone's receptors. This ensures a greater response from the target cell.
-
Describe desensitization of hormones.
A downregulation occurs, where the amount of a hormone's receptors decreases. This is induced by prolonged exposure to a hormone.
-
Lipophilic hormone receptors can be found ________________.
in the target's cell cytoplasm/nucleus
-
The function of most lipophilic hormones is ______________.
genomic action, where transcription is effected.
-
Hydrophilic hormone receptors can be found ______________________.
on the surface of a target cell
-
The function of most hydrophilic hormones (including some steroids) is _____________________.
nongenomic action, a process in which second messengers are involved
-
Define axis.
A control system that usually involves three structures. In the endocrine system, each of the structures produce a hormone that induces the next structure, until a wanted outcome occurs.
-
List some examples of axes.
- 1) Hypothalamus-pituitary-adrenal
- 2) Hypothalamus-pituitary-thyroid
- 3) Hypothalamus-fat axis
- 4) Renin-angiotensin-aldosterone
-
Define binding site.
The portion of a molecule where a ligand binds.
-
Define receptor site.
The binding site on a receptor.
-
What factors determine how effective a hormone is?
- 1) The concentration of the hormone in the blood.
- 2) The number of the hormone receptors in the cell.
- 3) The affinity of the receptor for that hormone.
-
What factors effect the duration of a hormonal action?
- 1) The rate of release.
- 2) The hormone's half-life.
-
What molecule acts as a precursor to all steroidal hormones?
Cholesterol
-
Where is cholesterol mostly found?
In the mitochondria
-
Arachidonic acid serves as a precursor to _________________.
prostaglandins
-
Prostaglandins carry the functions of 1) __________ and 2) __________ of blood vessels.
- 1) vasodilation
- 2) vasoconstriction
-
Prostaglandins are derived from _________________.
fatty acids or phospholipids
-
Which tissues produce prostaglandins?
ALL
|
|
