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Endocrinology > Introduction to Endocrine System > Flashcards

Introduction to Endocrine System Flashcards

1
Q

What are hormones?

A

Regulatory substances produced in a gland that stimulate specific cells into action

The term ‘hormone’ is derived from the Greek verb ‘hormao’, meaning ‘to set in motion’.

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2
Q

What are the major physiologic processes controlled by hormones?

A
  • Growth and maturation
  • Metabolism
  • Reproduction
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3
Q

What distinguishes endocrine glands from exocrine glands?

A

Endocrine glands secrete hormones into the blood, while exocrine glands secrete through ducts onto surfaces.

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4
Q

Name two types of communication used by hormones.

A
  • Communication between different endocrine glands
  • Communication between an endocrine gland and a target organ
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5
Q

What is the role of hormone receptors?

A

Proteins located inside the cell or on the cell membrane that bind to hormones and initiate cellular responses.

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6
Q

What are the two main types of hormones?

A
  • Peptide-derived hormones
  • Steroid hormones
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7
Q

What is the function of second messengers in hormone signaling?

A

Activate intracellular enzymes and amplify hormonal signals.

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8
Q

True or False: Steroid hormones can be stored in secretory vesicles.

A

False

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9
Q

Fill in the blank: The term __________ was coined by Starling in 1905 to describe hormones secreted internally.

A

[endocrine]

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10
Q

List examples of hydrophilic hormones.

A
  • Insulin
  • Epinephrine
  • Glucagon
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11
Q

What is a bound hormone?

A

A hormone that is attached to a transport protein.

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12
Q

What is the difference between free hormones and bound hormones?

A

Free hormones are unbound and biologically active; bound hormones are attached to transport proteins and inactive.

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13
Q

What are the effects of hormones on the body?

A
  • Control growth
  • Change sexual function
  • Regulate metabolism
  • Balance water and electrolytes
  • Breastmilk production
  • Uterine contraction
  • Temperature regulation
  • Sleep-wake cycle
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14
Q

What type of hormones are derived from cholesterol?

A

[steroid hormones]

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15
Q

What is the significance of the ‘free fraction’ of a hormone?

A

It refers to the percent of hormone that is unbound and biologically active.

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16
Q

Describe the structure of peptide hormones.

A

Made from chains of amino acids, and can be large proteins such as growth hormone.

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17
Q

What is the role of transport proteins in hormone circulation?

A

Protect hormones from degradation and increase their half-life in the bloodstream.

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18
Q

Name two examples of amino acid-derived hormones.

A
  • Epinephrine
  • Thyroxine
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19
Q

Fill in the blank: The interaction of a single hormone molecule with a receptor can lead to __________ signal-generating events within a cell.

A

[multiple]

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20
Q

What are the two types of feedback loops in hormone signaling?

A
  • Positive feedback loops
  • Negative feedback loops
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21
Q

True or False: Hydrophobic hormones can easily cross the cell’s plasma membrane.

A

True

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22
Q

What is the effect of increased blood binding protein during pregnancy on hormone concentration?

A

It can change the total amount of hormone but will not affect the concentration of free hormone.

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23
Q

What is the laboratory result for TSH in the presented clinical case?

A

0.6 (0.4 - 4.0 mU/L)

TSH stands for Thyroid-Stimulating Hormone.

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24
Q

What is the Total T4 level in the clinical case?

A

15 (5-12 ug/dl)

Total T4 refers to the total amount of thyroxine in the bloodstream.

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25
Q

What is the Free T4 level in the clinical case?

A

1.2 (0.9 - 1.8 ng/dL)

Free T4 is the fraction of thyroxine that is not bound to proteins.

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26
Q

What could explain the lab findings in the clinical case despite the absence of hyperthyroid symptoms?

A

Possible lab error, medication effects, or physiological variations

Hyperthyroidism symptoms may be absent despite lab findings indicating elevated thyroid hormones.

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27
Q

What are the solubility characteristics of steroid hormones?

A

Hydrophobic

Steroid hormones include cortisol, aldosterone, and sex hormones.

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28
Q

What type of receptors do steroid hormones bind to?

A

Intracellular receptors

These receptors are typically found in the cytoplasm or nucleus.

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29
Q

What is the plasma half-life of peptide hormones?

A

Short (minutes)

Peptide hormones include insulin and glucagon.

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30
Q

What is the main mechanism of hormone regulation?

A

Negative feedback

Negative feedback inhibits secretion of hormones based on their levels in the bloodstream.

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31
Q

What is an example of positive feedback in the endocrine system?

A

Oxytocin release during childbirth

Oxytocin enhances uterine contractions, leading to more release until delivery.

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32
Q

What can cause hormone overproduction?

A

Increase in hormone-producing cells

An example is hyperthyroidism associated with Graves’ disease.

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33
Q

What is a common cause of hormone underproduction?

A

Autoimmunity, as seen in Hashimoto’s hypothyroidism

Other causes include surgical removal of glands or infections.

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34
Q

What is the most common disorder seen by endocrinologists?

A

Diabetes mellitus

This includes both Type I and Type II diabetes.

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35
Q

What are the methods of testing endocrine function?

A
  • Plasma
  • 24 Hour urine collection
  • Saliva testing

These methods help in assessing hormone levels.

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36
Q

What is the role of cortisol in the endocrine system?

A

Regulates metabolism and stress response

Cortisol levels vary according to circadian rhythms.

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37
Q

Fill in the blank: Hormones are used for their _______ or suppressive effects.

A

replacement

Hormones can also be used therapeutically to treat various conditions.

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38
Q

What are the challenges in hormone replacement therapy?

A

Variability in normal ranges and mimicking normal physiology

Hormone replacement may not perfectly replicate natural hormone levels.

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39
Q

What endocrine disorder is associated with adrenal insufficiency?

A

Addison’s Disease

This condition results from insufficient production of adrenal hormones.

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40
Q

What is a common endocrine disorder related to the thyroid gland?

A

Hashimoto’s thyroiditis

This is an autoimmune condition leading to hypothyroidism.

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41
Q

What type of hormone testing measures the response to stimulation or suppression?

A

Stimulation or suppression testing

This testing helps assess the functional capacity of endocrine glands.

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42
Q

What hormone is primarily responsible for regulating blood glucose levels?

A

Insulin

Insulin is secreted by pancreatic beta cells.

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43
Q

True or False: Peptide hormones are hydrophilic and do not bind to transport proteins.

A

True

Peptide hormones circulate freely in the blood.

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44
Q

What is the clinical role of endocrinologists?

A

Consultation, treatment, and management of endocrine disorders

They often work in outpatient settings.

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45
Q

What is the significance of cortisol measurement timing?

A

Early morning and late evening measurements are most appropriate

Cortisol levels fluctuate throughout the day.

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46
Q

What are the effects of hormone resistance?

A

Altered tissue response to hormones

Examples include insulin resistance in type 2 diabetes.

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47
Q

What is a characteristic of steroid hormone production?

A

Regulated at the level of synthesis

Steroid hormones cannot be stored in secretory vesicles.

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48
Q

Fill in the blank: Hormones are regulatory substances produced in an _______ gland.

A

endocrine

Endocrine glands include the thyroid, adrenal, and pituitary glands.

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49
Q

What are membrane-bound secretory vesicles responsible for?

A

The release of these vesicles represents a regulated mode of exocytosis.

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50
Q

What is a prehormone?

A

A prehormone is a hormone that contains a signal peptide guiding the polypeptide into the endoplasmic reticulum.

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51
Q

What are frequently synthesized as preprohormones?

A

Hormones.

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52
Q

What happens to the signal peptide in the synthesis of hormones?

A

It is removed to process the prohormone by prohormone convertases.

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53
Q

Do hormones typically cross cell membranes?

A

No, they typically do not cross cell membranes and act through transmembrane receptors.

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54
Q

How do most hormones circulate in the body?

A

As free hormones.

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55
Q

What are the primary methods used in endocrinology for hormone measurement?

A

Antibody-based methods.

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56
Q

Why are small changes in hormone levels important?

A

They are often more specific and earlier indicators of disease than physical symptoms.

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57
Q

What challenges are associated with measuring hormone levels?

A

Concentrations of most hormones are much lower than those of general chemistry analytes.

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58
Q

What replaced earlier chromatographic/mass spectrometric methods in hormone measurement?

A

Antibody methods.

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59
Q

What types of assays were initially utilized for hormone measurement?

A

Competitive binding assays using polyclonal antibodies.

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60
Q

What assay method is used for measuring antigens with multiple antibody-binding epitopes?

A

Immunometric assay.

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61
Q

Where are hormone receptors found in cells?

A

On the surface, in the cytosol, or in the nucleus of the cells.

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62
Q

What characterizes transmembrane receptors?

A

They span the thickness of the cell membrane with the hormone-binding molecule on the outer surface.

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63
Q

How many receptor molecules are usually present in target cells?

A

Usually only a few thousand receptor molecules.

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64
Q

How can cells adjust their responsiveness to hormones?

A

By changing the number of receptors they express based on the signal received.

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65
Q

What can intense stimulation cause in terms of receptor expression?

A

It may cause a cell to downregulate the number of receptors expressed.

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66
Q

What is the embryonic origin of the pineal body?

A

Neuroectoderm from the prosencephalon, then diencephalon

Initially a hollow diverticulum that becomes a solid organ of pinealocytes.

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67
Q

What hormone is secreted by pinealocytes?

A

Melatonin

Secretion is cyclic, lowest during daylight hours.

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68
Q

What influences the secretion of GnRH by the hypothalamus?

A

Melatonin

Inhibits GnRH secretion until puberty.

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69
Q

What are the main axes associated with the hypothalamus?

A
  • HPG axis
  • HPA axis
  • HPT axis
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70
Q

What is the embryonic origin of the pituitary gland?

A

Neural ectoderm (neurohypophysis) and surface ectoderm (adenohypophysis from Rathke’s pouch)

Development involves the elongation and connection to the infundibulum.

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71
Q

At what week is growth hormone detectable in the developing pituitary?

A

Week 10

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72
Q

What is the primary function of the thyroid gland by week 10 of development?

A
  • Neural development
  • Metabolism
  • HPT axis
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73
Q

What structures do the parathyroid glands develop from?

A
  • 3rd Pharyngeal Pouch (inferior parathyroid)
  • 4th Pharyngeal Pouch (superior parathyroid)
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74
Q

What is the sequence of pancreatic hormone differentiation?

A
  • Glucagon (alpha cells)
  • Somatostatin (delta cells)
  • Insulin (beta cells)
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75
Q

What does the zona fasciculata of the adrenal cortex produce?

A

Cortisol

Functions include increasing blood sugar and suppressing the immune system.

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76
Q

What role do primordial germ cells (PGCs) play in gonad development?

A

PGCs migrate into the developing gonads

They are involved in the differentiation of the gonads into testes or ovaries.

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77
Q

What gene is crucial for testis development?

A

Sry gene

Located on the short arm of the Y chromosome.

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78
Q

What hormone do Leydig cells secrete?

A

Testosterone

79
Q

What is the role of the corpus luteum during pregnancy?

A

Maintains pregnancy in response to endocrine signals from the implanting conceptus

Produces progesterone and other hormones.

80
Q

What are the key protein hormones produced by the placenta?

A
  • Chorionic gonadotropin (hCG)
  • Chorionic somatomammotropin (hCS)
  • Chorionic thyrotropin (hCT)
  • Chorionic corticotropin (hCACTH)
81
Q

What is the function of Atrial Natriuretic Peptide (ANP)?

A

Increase filtration rate and decrease Na+ reabsorption

Levels are higher in fetal circulation than in adults.

82
Q

True or False: The pancreas primarily plays a role in development.

A

False

The pancreas has metabolic functions but not a significant role in development.

83
Q

What are the ducts associated with the male reproductive system?

A
  • Mesonephric duct
  • Epididymis
  • Vas deferens
  • Seminal vesicles
84
Q

What happens to Müllerian structures in the absence of testosterone?

A

They form uterine tubes, uterus, and upper portion of the vagina.

85
Q

What do ductless glands secrete into the blood?

A

Hormones

Hormones are signaling molecules that bind to receptors on target cells.

86
Q

What types of actions can hormones have?

A

Endocrine, paracrine, autocrine

These actions refer to the different ways hormones can affect target cells.

87
Q

What is the primary role of hormones?

A

Regulation and homeostasis

88
Q

What is the origin of most hormones?

A

Mostly epithelia; some mesenchymal (e.g., adrenal cortex)

89
Q

What are the different cellular arrangements found in endocrine glands?

A
  • Follicles (thyroid)
  • Cords (adrenal)
  • Nests (parathyroid)
  • Clusters (hypothalamus)
90
Q

What system consists of individual endocrine cells?

A

Diffuse Neuroendocrine System (DNES)

91
Q

What is the largest group of hormones?

A

Peptides

Examples include insulin, GH, glucagon, LH, ADH.

92
Q

How do peptide hormones behave in solution?

A

Polar: dissolve in plasma (no carrier protein)

93
Q

Where do peptide hormones bind their receptors?

A

Cell surface

94
Q

What type of hormones are steroids?

A

Non-polar (require carrier protein)

Examples include testosterone, progesterone, aldosterone, cortisol.

95
Q

Where do steroid hormones bind their receptors?

A

Cytoplasm/nucleus

96
Q

What is the classification of amino acid-derived hormones?

A

Polar

Examples include epinephrine, histamine.

97
Q

Where do amino acid hormones bind their receptors?

A

Cell surface

98
Q

What is the pituitary gland morphologically and functionally linked to?

A

Hypothalamus

99
Q

What are the two main parts of the pituitary gland?

A
  • Anterior (glandular epithelia)
  • Posterior (Neural)
100
Q

What are the subdivisions of the anterior pituitary?

A
  • Pars distalis
  • Pars intermedia
  • Pars tuberalis
101
Q

What is found in the posterior pituitary?

A
  • Infundibular stalk (axons)
  • Pars nervosa (axons & endings)
102
Q

What percentage of the pituitary is basophilic?

A

10% basophilic

103
Q

What are the types of tropic hormones in the pituitary?

A
  • ACTH (basophils)
  • FSH (basophils)
  • LH (basophils)
  • TSH (basophils)
104
Q

What are the non-tropic hormones in the pituitary?

A
  • GH (acidophils)
  • Prolactin (acidophils)
105
Q

What is the role of the neurohypophysis?

A

Storage

Contains pituicytes (neuroglial) and unmyelinated axons.

106
Q

What are Herring bodies?

A

Expanded axon terminals containing oxytocin or ADH

107
Q

What are the three axes associated with the hypothalamus?

A
  • HPG axis
  • HPA axis
  • HPT axis
108
Q

What shape is the pineal gland?

A

Pine-cone shaped

109
Q

What are the two types of cells in the pineal gland?

A
  • Pinealocytes
  • Interstitial cells (glial)
110
Q

What are ‘brain sand’ markers in the pineal gland?

A

Corpora arenacea

111
Q

What is the primary function of the pineal gland?

A

Release melatonin

112
Q

What does melatonin regulate?

A
  • Circadian rhythms
  • Menstrual cycle (inhibition of GnRH)
113
Q

What can destruction of the pineal gland lead to?

A

Early onset puberty

114
Q

True or False: Seasonal affective disorder (SAD) is altered by the pineal gland’s response to day length.

115
Q

What are the secretory units of the thyroid organized into?

A

Follicles

Follicles are spherical structures lined with follicular cells.

116
Q

What types of cells line the thyroid follicles?

A

Follicular cells and parafollicular cells

Follicular cells are slightly basophilic, while parafollicular cells appear pale.

117
Q

What hormones do follicular cells of the thyroid secrete?

A

Triiodothyronine (T3) and thyroxine (T4)

These hormones are crucial for regulating metabolism.

118
Q

What substance do T3 and T4 bind to in the thyroid?

A

Thyroglobulin (colloid)

Most thyroid follicles are filled with stored thyroglobulin.

119
Q

What hormone is secreted by parafollicular cells?

A

Calcitonin

Parafollicular cells are not exposed to the follicular lumen.

120
Q

What are the principal cells of the parathyroid gland called?

A

Chief cells

Chief cells secrete parathyroid hormone (PTH).

121
Q

What type of cells in the parathyroid gland are acidophilic and appear during puberty?

A

Oxyphil cells

These cells are less understood compared to chief cells.

122
Q

What is the percentage composition of the adrenal cortex’s zona glomerulosa?

A

15%

Zona glomerulosa is responsible for secreting mineralocorticoids.

123
Q

What types of hormones are produced by the zona fasciculata of the adrenal cortex?

A

Glucocorticoids

Zona fasciculata comprises 80% of the adrenal cortex.

124
Q

What is the primary function of the adrenal medulla?

A

Produce epinephrine and Chromogranin A

The adrenal medulla consists of sympathetic neuronal tissue.

125
Q

What is the primary function of the endocrine pancreas?

A

Secretes hormones to regulate blood glucose

The endocrine component constitutes 1-2% of the pancreas.

126
Q

What structure in the pancreas is associated with digestion?

A

Exocrine pancreas

The exocrine pancreas makes enzymes for food digestion.

127
Q

What are the main cell types found in the Islets of Langerhans?

A

Alpha, Beta, Delta, F cells, D1 cells, EC cells, Epsilon cells

Each cell type secretes different hormones such as glucagon, insulin, and somatostatin.

128
Q

What hormone is secreted by alpha cells in the pancreas?

A

Glucagon

Alpha cells make up 15-20% of the pancreatic islet cells.

129
Q

What hormone is secreted by beta cells in the pancreas?

A

Insulin

Beta cells constitute 60-70% of the pancreatic islet cells.

130
Q

Fill in the blank: The adrenal cortex’s zona reticularis produces _______.

A

Gonadocorticoids

Zona reticularis comprises 5-7% of the adrenal cortex.

131
Q

True or False: Fatty infiltration occurs in the parathyroid gland as aging occurs.

A

True

This is a common observation in aging parathyroid glands.

132
Q

What is the histological significance of the thyroid and parathyroid glands?

A

Functional significance of their hormonal products

Understanding their histological organization is crucial in clinical contexts.

133
Q

What are the two main functions of the pancreas?

A

Endocrine and Exocrine

The pancreas plays a dual role in hormone secretion and enzyme production.

134
Q

Define autocrine cell communication

A

released by a cell to regulate itself

135
Q

describe how neurocrine cellular communication works

A

signaling b/t adjacent cells via gap junctions

136
Q

How does paracrine signaling typically work

A

similar to neurocrine signaling but more intended to regulate a large group of cells

137
Q

what peptide hormone is hydrophobic?

A

thyroid hormone

138
Q

compare & contrast the differences b/t Addison’s & Cushing’s diseasee

A

Addison: underproduction of cortisol hormones
chshing: overproduction of cortisol hormones

139
Q

what are some examples of hormonal disorders of the pituitary gland

A

Acromegaly, hyperprolactinemia, pituitary adenoma causing secondary cushing’s disease

140
Q

what factors determine oral hormone dosage & bioavailability

A

GI absorption & first-pass kinetics

141
Q

oral administration is more appropriate for what type of hormone?

A

steroids & thyroid hormones

142
Q

Parenteral administration is most appropriate for what type of hormones

A

peptide analogues
eg: insulin, PTH, GH

143
Q

Standardized normal ranges for hormone levels is clinically problematic for what reasons?

A

These ranges are wide and therefore not very reliable measures for determining the presence or absence of an endocrine disease

144
Q

True or false: maternal melatonin can cross the placenta.

A

True
Mechanism & function not well-understood

145
Q

The hypothalamus is derived from what embryonic structures?

A

derived from the diencephalon (evidence also supports telencephalon origin)
ventro-lateral wall intermediate zone proliferates and forms the primordial hypothalamus

146
Q

List the components of the HPG axis

A

H: Hypothalamus-GnRH
P: Pituitary-LH & FSH
G: ovaries-progesterone & estrogen

147
Q

List the components of the HPA axis.

A

H: Hypothalamus-CRH
P: Anterior Pituitary-ACTH
A: adrenal gland-cortisol

148
Q

List the components of the HPT axis

A

H: hypothalamus-TRH
P: anterior pituitary-TSH
T: thyroid-T3 & T4

149
Q

The anterior pituitary originates from what embryonic structure and what is the clinical significance of this

A

originates from the Rathke pouch

this pouch is ectodermal in origin derived from oropharynx-ectopic hormone secreting tumors are derived from endocrine cells in the oro & naso pharnxy

150
Q

endocrine glands that specifically produce steroid hormones arise from which embryonic layer?

151
Q

What hormones does the fetus secrete endogenously? List in chronological order from beginning to end of gestation.

A

7 weeks: ACTH
8 weeks: GH
12 weeks: TSH, LH, & FSH

152
Q

What embryologic processes does prolactin participate in and at what week of gestation can fetal prolactin be detected

A

Can be detected starting at 24 weeks
Inhibition of GnRH secretion from the hypothalamus
stimulates proliferation of oligodendrocyte cells involved in production of lung surfactant

153
Q

what is the first gland to develop in the fetus?

A

thyroid gland

154
Q

GH stimulate follicular growth in the thyroid. True or False.

155
Q

At birth, TSH, T3, T4 are very low but increase after the first 5-7 days of life. True or False?

A

False
it’s the other way around: levels are high at birth and subside within the first week of life

156
Q

Later onset of fetal TSH secretion stimulates the production of what

157
Q

The parathyroid is derived from the ectoderm. True or False?

A

False
PTG is derived from the endoderm

158
Q

What pancreatic structures are derived from the dorsal primordium?

A

body, tail, & superior/anterior head
accessory duct

159
Q

what pancreatic structures are derived from the ventral primordium?

A

posterior/inferior head
main pancreatic duct

160
Q

The pancreatic buds arise out of what embryonic structures

A

outpouchings of the duodenal endoderm

161
Q

True or false: the fetus starts producing pancreatic hormones at 7-8 weeks gestation.

162
Q

The adrenal gland is derived from the endoderm. True or false.

A

FALSE
It’s the mesoderm

163
Q

The renal medulla is derived from what embryonic layer?

164
Q

The renal medulla, adrenal glands, & gonads all originate from what embryonic structure?

A

mesonephros

165
Q

The gonads are derived from the mesoderm. True or false.

166
Q

The absence of TDF (encoded on the SRY gene) will determine what fate in the gonads

A

development of ovaries

167
Q

The sertoli cells stimulate the degeneration of what embryonic structure?

A

the Mullerian duct

168
Q

What can happen if the sertoli cells fail to degenerate the the mullerian duct?

A

Partial/Inappropriate development of female genitalia

169
Q

If testosterone is not present by 10 weeks of gestation, what is the most likely fate of the wolffian and mullerian ducts

A

The wolffian ducts degenerate and male genitalia will not be formed while the mullerian will continue to develop and form the fallopian tubes, uterine tissues & upper portions of the vagina

170
Q

Wolffian duct development stimulates the formation of male external genitalia. True or False. If false, explain your reasoning

A

Not entirely false nor true
Wolffian ducts form the internal male genitalia
DHT stimulation for the development of external male genitalia depends on wolffian duct development

171
Q

follicles secrete what hormone?

172
Q

The external male genitalia are derived from what embryonic structure in the Wolffian ducts?

A

the mesonephric ducts

173
Q

What is the ultimate fate of the mesonephric duct in the male and the female?

A

Male: mesonephric ducts persists and become the epididymis, Vas Deferens, & seminal vesicles
Female: mesonephric ducts degenerate due to the absence of testosterone

174
Q

what are important biomarkers of cardiac organogenesis?

175
Q

What role do endothelins play in fetal development

A

regulation of fetal HR
Induces myocyte differentiate into purkinje fibers

176
Q

High levels of ANP in adults indicates what?

A

ventricular hypertrophy

177
Q

What is the role of hCG?

A

supports corpus luteum
facilitates adrenal cortex growth

178
Q

What is the role of hCS?

A

stimulates maternal metabolic processes and breast growth

179
Q

what hormone is the primary maintanace hormone for continuation of pregnancy?

A

progesterone

180
Q

what fetal hormone supports and maintains the maternal endometrium?

181
Q

what is the definition of a tropic hormone?

A

hormones that are secreted to stimulate downstream secretion of hormones from another endocrine organ

182
Q

what is the definition of a non-tropic hormone?

A

directly stimulate target cells to induce effects

183
Q

acidophils produce what hormones?

A

GH & prolactin

184
Q

basophils secrete what hormones?

A

ACTH, FSH, LH, TSH

185
Q

The posterior pituitary glands contain what hormones

A

oxytocin & ADH

186
Q

what is the main content in thyroid follicular cells?

A

stored thyroglobulin (colloid)

187
Q

T3 & T4 bind to what protein

A

thyroglobulin

188
Q

What happens to the parathyroid as it ages?

A

fatty infiltration

189
Q

Oxyphil cells facilitate the puberty process. True or false?

190
Q

What is the function of Chromogranin A?

A

precursor to autocrine neuropeptides

191
Q

The zona glomerulosa produces what type of corticoids?

A

mineralocorticoids

192
Q

the zona fasciculata produces what type of corticoids?

A

glucocorticoids

193
Q

the zona reticularis produces what type of corticoids?

A

gonadocorticoids

Endocrinology (9 decks)

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