Lecture Notes - Endocrine, Immune, Cardiovascular, Respiratory, and Lymphatic Systems (Vocabulary)

Vocabulary flashcards covering key terms and their definitions from the lecture notes. Some terms reflect corrections to common misconceptions seen in the notes to ensure accurate study material.

T3 (triiodothyronine)

Main active thyroid hormone that increases metabolic rate; derived from T4; requires iodine.

T4 (thyroxine)

Thyroid hormone produced in larger amount; converted to T3 in tissues to regulate metabolism.

ADH (antidiuretic hormone)

Stored in and released from the posterior pituitary; promotes water reabsorption in kidneys.

Oxytocin

Posterior pituitary hormone that stimulates uterine contractions and milk ejection.

Luteinizing Hormone (LH)

Anterior pituitary gonadotropin; triggers ovulation and stimulates testosterone production.

Epinephrine (adrenaline)

Adrenal medulla hormone; part of fight‑or‑flight; increases heart rate, bronchodilation, and blood flow changes.

Norepinephrine (noradrenaline)

Adrenal medulla hormone; works with epinephrine to mobilize body during stress.”

Cortisol

Adrenal cortex glucocorticoid; increases blood glucose; aids in stress response and anti‑inflammatory effects.

Aldosterone

Adrenal cortex mineralocorticoid; promotes Na+ retention and K+ excretion; raises blood pressure.

Androgens (adrenal)

Adrenal cortex sex hormones; precursors to or converted into androgens/estrogens.

ACTH (adrenocorticotropic hormone)

Anterior pituitary hormone; stimulates adrenal cortex to secrete cortisol and other corticosteroids.

PTH (parathyroid hormone)

Raises blood calcium by stimulating osteoclasts and increasing calcium reabsorption in kidneys.

Calcitonin

Lowers blood calcium by inhibiting osteoclast activity.

Growth Hormone (GH)

Anterior pituitary hormone; promotes growth and metabolism; essential for development.

TSH (thyroid-stimulating hormone)

Anterior pituitary hormone; stimulates thyroid to release T3 and T4.

FSH (follicle-stimulating hormone)

Anterior pituitary gonadotropin; stimulates gamete production in ovaries and testes.

LH (luteinizing hormone)

See above (duplicate term included for emphasis).

GnRH (Gonadotropin-releasing hormone)

Hypothalamic hormone that stimulates release of LH and FSH from the anterior pituitary.

GHRH (growth hormone-releasing hormone)

Hypothalamic hormone that stimulates release of growth hormone from the anterior pituitary.

Prolactin (PRL)

Anterior pituitary hormone; promotes milk production in the mammary glands.

ADH (antidiuretic hormone) – notes correction

Chemical term and function as above; helps maintain fluid balance by concentrating urine.

Hemoglobin

Protein in red blood cells that binds and transports oxygen and some carbon dioxide.

Albumin

Most abundant plasma protein; maintains colloid osmotic (oncotic) pressure and blood volume.

ABO blood group system

System of blood types determined by surface antigens A and B on RBCs and corresponding antibodies.

Type A

A antigen on RBCs; anti‑B antibodies in plasma.

Type B

B antigen on RBCs; anti‑A antibodies in plasma.

Type AB

Both A and B antigens on RBCs; no anti‑A or anti‑B antibodies.

Type O

No A or B antigens on RBCs; anti‑A and anti‑B antibodies in plasma.

Common coagulation pathway

Coagulation cascade involving factors I, II, V, and X leading to thrombin formation and fibrin synthesis.

Elastic arteries

Large arteries (e.g., aorta) with abundant elastin to accommodate pulse pressure.

Pulmonary circulation vs systemic circulation

Pulmonary: carries blood to/from lungs for gas exchange; systemic: supplies body tissues.

Right lung vs Left lung lobes

Right lung has three lobes; left lung has two lobes due to cardiac position.

Apex of the heart

Bottom tip of the heart, usually formed by the left ventricle; located toward the left fifth intercostal space.

Hilum of the lung

Indented medial area where bronchi, blood vessels, and nerves enter/exit the lung.

Eustachian (auditory) tube

Connects middle ear to nasopharynx; equalizes middle ear pressure.

MALT (mucosa-associated lymphoid tissue)

Lymphoid tissue in mucosal surfaces providing immune protection at mucosal sites.

Peyer’s patches

Lymphoid tissue in the ileum that helps protect the gut from ingested pathogens.

Lacteals

Lymphatic capillaries in intestinal villi that absorb dietary fats.

Interferons

Cytokines produced by cells in response to viruses; help inhibit viral replication and modulate immunity.

Complement system

Group of plasma proteins that enhance immune responses; classical pathway requires antigen presentation.

First line of defense

Barriers like skin and mucous membranes that prevent pathogen entry.

Second line of defense

Non‑specific responses (phagocytes, inflammation, fever, interferons, complement).

Lymphocytes (T, B, NK cells)

Adaptive immune cells: T cells, B cells, and natural killer cells with distinct roles.

CD4+ helper T cells

Coordinate immune responses; activate other immune cells via cytokines.

Trachea and bronchi

Airways conducting air; trachea divides into bronchi that branch into smaller bronchioles.

Upper vs lower respiratory tract

Upper: nose to trachea; lower: airways within the lungs and alveoli.

Cilia and mucous in airways

Protective mechanisms in conducting zone that trap and remove particles.