Endocrine & Respiratory Systems – Key Vocabulary

Vocabulary flashcards summarizing essential endocrine and respiratory terms, hormones, cell types, and related pathologies from the lecture notes.

Pituitary Gland

Endocrine organ in sella turcica; composed of anterior (adenohypophysis) and posterior (neurohypophysis) lobes.

Infundibular Stalk

Connection between hypothalamus and pituitary gland that transmits vascular and neural signals.

Hypophysis or Master’s gland

Pituitary gland is also known as ___

Adenohypophysis

Anterior pituitary lobe that synthesizes and secretes hormones such as GH, PRL, FSH, LH, ACTH, and TSH.

Neurohypophysis

Posterior pituitary lobe that stores and releases hypothalamic hormones oxytocin and ADH.

Growth Hormone (Somatotropin)

Anterior pituitary hormone promoting chondrogenesis, protein anabolism, glycogenolysis, and lipolysis.

Prolactin

Anterior pituitary hormone that stimulates milk production in mammary glands.

Follicle-Stimulating Hormone (FSH)

Basophil hormone that initiates gametogenesis and estrogen production; supports ABP synthesis in males.

Luteinizing Hormone (LH)

Basophil hormone triggering ovulation and corpus luteum formation; induces testosterone synthesis in males.

Adrenocorticotropic Hormone (ACTH)

‘Corticotropin’; stimulates zona fasciculata of adrenal cortex to secrete cortisol.

Thyroid-Stimulating Hormone (TSH)

‘Thyrotropin’; prompts thyroid follicular cells to release T3 and T4.

Cushing’s disease

EXCESSIVE CORTISOL will result to?

Addison’s disease

DEFICIENT CORTISOL will result to?

Hyperthyroidism

EXCESSIVE THYROID HORMONES will result to?

Hypothyroidism

DEFICIENT THYROID HORMONES will result to?

21 days

Hormonal pills are usually taken for how many days?

Progesterone and estrogen

Main hormone for pregnancy and menstruation?

Posterior Pituitary gland (Neurohypophysis)

Doesn’t SYNTHESIZE hormones but STORES and SECRETES hormones PRODUCED by Hypothalamus

28 days

Average menstrual cycle

Gonadotropin-releasing hormones

At pubertal age, the hypothalamus releases this hormone

Endometrial hyperplasia

Thickening of endometrium

Graafian follicles

Estrogen stimulates the maturation of ovarian primordial cells to mature into _____

Corpus albicans

If fertilization do not happen, the CORPUS LUTEUM will turn into ____

Oxytocin

Paraventricular-derived hormone causing uterine contractions and milk ejection; released via positive feedback from cervical stretch or suckling.

Antidiuretic Hormone (ADH, Vasopressin)

Supraoptic-derived hormone that increases water reabsorption in renal tubules and constricts arterioles, raising BP.

Diabetes Insipidus

Disorder caused by ADH deficiency leading to polyuria and polydipsia.

Thyroid Gland

Largest endocrine gland; butterfly-shaped, located below thyroid cartilage with right and left lobes connected by an isthmus.

Isthmus (Thyroid)

Median tissue bridge joining right and left thyroid lobes/gland

Follicular Cells

Thyroid cells that produce T3 (triiodothyronine) and T4 (thyroxine) to regulate metabolism and growth.

Parafollicular Cells (C cells)

Thyroid cells secreting calcitonin to lower blood calcium levels.

Triiodothyronine (T3)

Active thyroid hormone that elevates metabolic rate and supports nervous system development.

Thyroxine (T4)

Pro-hormone converted to T3; contributes to overall metabolic regulation.

Calcitonin

Thyroid hormone that decreases blood calcium by enhancing bone formation.

Thyroid hormones

Which hormones needs IODINE to be produced?

Hyperthyroidism

Condition of excess thyroid hormone causing elevated metabolism; commonly due to Graves’ disease.

Grave’s disease

Most common cause of hyperthyroidism is?

Epinephrine

• Drug contraindicated for (unstable) hyperthyroidism?

Prophylthiouracil (PTU) or Methimazole

Drugs for Hyperthyroidism?

Hypothyroidism

Deficiency of thyroid hormone; most often from Hashimoto thyroiditis; severe adult form is myxedema, in children causes cretinism.

Hashimoto’s thyroiditis or Iodine deficiency

Most common cause of hypothyroidism is?

Cretinism (mental retardism, physical retardism)

Hypothyroidism in children may result to?

Myxedema

Severe type of hypothyroidism?

Synthetic thyroxine (ex. Levothyroxine)

Drugs for Hypothyroidism?

Parathyroid Glands

Four small glands on posterior thyroid that secrete parathyroid hormone (PTH).

Parathyroid Hormone (PTH)

Chief-cell hormone raising blood calcium via bone resorption, renal Ca²⁺ reabsorption, and calcitriol activation.

Chief Cells

Parathyroid cells responsible for synthesizing PTH.

Sodium

Which hormone is stimulated by Aldosterone to be reabsorbed?

Antidiuretic hormone

Which hormone allows reabsorption of water from renal tubule?

Aldosterone

▪ End product of Renin-Angiotensin-Aldosterone-System (RAAS)

▪ ↑ Na⁺ and H₂0 reabsorption in the CT/C

Mineralocorticoid from zona glomerulosa that promotes Na⁺/water reabsorption and K⁺/H⁺ secretion in kidney, regulating BP.

Adrenal (Suprarenal) Glands

Located superior to the kidney

Adrenal cortex

Outer part of the adrenal gland

Renin-Angiotensin-Aldosterone System (RAAS)

Hormonal cascade activated by low blood volume/pressure leading to aldosterone release.

Zona Glomerulosa

Outer adrenal cortex layer that secretes natural mineralocorticoids, primarily aldosterone.

Zona Fasciculata

Middle adrenal cortex layer secreting natural glucocorticoids, primarily cortisol.

Cortisol

Primary stress glucocorticoid that increases gluconeogenesis, lipolysis, protein catabolism, and provides anti-inflammatory and immunosuppressive effects.

Cushing’s Disease

Hypersecretion of cortisol causing moon face and buffalo hump appearance

Addison’s Disease

Cortisol deficiency leading to hyperpigmentation, weight loss, and risk of adrenal crisis.

Zona Reticularis

Inner adrenal cortex layer that secretes androgens such as dehydroepiandrosterone (DHEA).

Androgens (Adrenal)

Steroid hormones regulating development and maintenance of male characteristics.

Adrenal Medulla

Middle part of adrenal gland which is made up of chromaffin cells that release catecholamines.

Chromaffin Cells

Modified sympathetic neurons that synthesize and secrete epinephrine, norepinephrine, and dopamine.

Catecholamines

Epinephrine, norepinephrine, and dopamine—hormones mediating sympathetic ‘fight or flight’ responses.

important for activation of sympathetic adrenergic receptors

Pancreas

Endocrine portion (tail/end part)

Islets of Langerhans

Tiny clusters of cells found in pancreas containing alpha, beta, and delta cells.

Alpha Cells

Pancreatic cells secreting glucagon, which raises blood glucose during hypoglycemia.

Glucagon

Hormone that increases blood glucose via glycogenolysis and gluconeogenesis.

Beta Cells

Pancreatic cells producing insulin to lower blood glucose levels.

Insulin

Anabolic hormone enabling cellular glucose uptake and storage, reducing blood glucose.

Delta Cells

Pancreatic cells releasing somatostatin, which inhibits GH, insulin, glucagon, and GI secretions.

Somatostatin

Inhibitory hormone from delta cells and hypothalamus that suppresses endocrine and GI activity.

80-110 mg/dl

What is the normal range for fasting blood sugar?

8-12 hours

Average fasting time before taking fasting blood sugar

Diabetes Mellitus Type I

Insulin-dependent, autoimmune destruction of beta cells leading to absolute insulin deficiency.

Diabetes Mellitus Type II

Non-insulin-dependent diabetes characterized by insulin resistance and relative deficiency.

Gestational Diabetes

Pregnancy diabetes

Glucose intolerance first recognized during pregnancy.

Polyphagia

Excessive hunger—part of diabetes mellitus symptom triad.

Polyuria

Excessive urination—common in diabetes and diabetes insipidus.

Polydipsia

Excessive thirst—result of fluid loss in diabetes.

Respiratory Epithelium

Lines by pseudostratified columnar epithelium ciliated with goblet cells

Goblet Cells

Mucus-secreting cells decreasing in number toward the alveoli

Ciliated Columnar Cells

Cilia helps for the expectoration of mucus

GAS EXCHANGE

_

• simple diffusion/passive diffusion

o Determined by Partial Oxygen (PO2) pressure and Partial CO2 (PCO2) pressure

External respiration

▪ Exchange of Gases between alveoli and blood

Internal respiration

Exchange of Gases between blood and cells

Conducting tree

Carries gas (NO GAS EXCHANGE in this region)

Nasopharynx

Respiratory epithelium (40%); nasopharyngeal epithelium (60%)

Oropharynx

Nasopharyngeal epithelium

Larynx

‘Voice box’ containing vocal cords; guarded by epiglottis during swallowing.

Epiglottis

Closes the larynx during swallowing

Vocal cords

Where initial sound is produced

Posterior cricoartenoid muscle

Which muscles opens the vocal chords?

Lateral cricoartenoid muscle

Which muscle closes the vocal chords?

Rima Glottidis

Opening of vocal cords through which air passes.

Trachea

“Windpipe” supported by C-shaped hyaline cartilage rings; divides into primary bronchi.

Bronchioles

Small airway branches lacking cartilage; lined by ciliated cuboidal cells and Clara cells.

Carina

Separates the right and left primary bronchi

Clara Cells (Club Cells)

non-ciliated cuboidal epithelium

Terminal Bronchioles

Most distal part of conducting zone; absence of goblet cells.

Cells present are ciliated cuboidal epithelium and clara cells

Respiratory Bronchioles

First airway segment involved in gas exchange; possess occasional alveoli in walls.

Alveolar Ducts

Channels completely lined by alveoli, leading to alveolar sacs.