Organs pt. 3: Endocrine, reproductive, immune Flashcards
Hormone
Chemical messengers produced by the endocrine system
Endocrine System
Regulated biological processes through glands and hormones. Messenger system of feedback loops
Hormone Connection
If water-soluble: Dock on protein, create signal transduction pathway
If Lipid soluble: move through cell membrane to inside cell/nucleus
10 main endocrine glands
- Pineal: In brain, secretes melatonin for circadian rhythm
- Anterior Pituitary: In brain, growth hormone, endorphins (relieve pain), follicle simulating hormone (puberty)
- Posterior pituitary: In brain, oxytocin (bonding, love, childbirth/contractions), ADH
- Thyroid: In neck, T3(triiodothyronine)/T4 (thyroxine) (# of iodine atoms) (speeds up metabolism), Calcitonin (lower calcium)
- Parathyroid: PTH (increase calcium)
- Pancreas: Behind stomach, beta cells (insulin), alpha cells (glucagon) (islets of langerhans)
- Adrenal Cortex: On top of kidneys (outside), glucocorticoids (anti-inflammatory), connected by hormones to pituitary
- Adrenal Medulla: On top of kidneys (inside), epinephrine/adrenaline (flight/fight), nervous connection to brain
- Ovaries: Gonads, mostly estrogen (female sex characteristics)
- Testes: Gonads, mostly testosterone (male sex characteristics)
Endo/exocrine
Endocrine: Hormones in blood
Exocrine: Chemical secretions out of skin (mammary/sweat glands)
Hypothalamus, pituitary relationship
Hypothalamus makes hormones, posterior pituitary holds/secretes. Anterior pituitary can create
Anterior Pituitary
Growth hormone, Prolactin (breast milk), Thyroid Stimulating Hormone (stimulates thyroid to release thyroid hormone), Follicle Stimulating Hormone (gonads to make gametes/puberty), Luteinizing Hormone (stimulate gonads to move androgens), Adrenocorticotropic hormone (stimulate adrenal cortex)
Thymus
Shrinks in adulthood, Site of T cell maturity, thymosin (stimulate T cell production)
Testes
Seminiferous tubules (spermatogenesis), enclosed in scrotum to maintain lower temperature (35).
Travel of sperm
- Seminiferous tubules
- Epididymis (convoluted tubule section) (store sperm/mature)
- Ejaculation - - Vas deferens
- Ejaculatory Duct
- Seminal Vesicle (releases nutrients: fructose/proteins)
- Urethra
- Prostate/bulbourethral gland (releases basic solution)
- Out
Female Gonads
Ovaries (oogenesis) after menstruation release ovum to fallopian tube. If fertilized by sperm, becomes zygote.
Uterus
Endometrium - Mucus layer provides nutrients and oxygen
Cervix connects uterus and vagina
Fertilization
Ovum and sperm are haploids that join to create diploid (embryological development)
1. Sperm reaches zona pellucida (glycoproteins), acrosome releases digestive enzymes to make hole
2. Plasma membrane depolarizes, ion channels open, cortical granules (vesicles) attach to membrane
3. Vesicles release enzymes to turn membrane to fertilization membrane (prevents other sperm from entering)
4. This is cortical reaction
Sperm parts
Tail (phlagella), head (organelles), acrosome (digestive enzymes)
Innate/Non-specific Immune System
What we are (mostly) born with. Attacks anything foreign in the same way (does not learn). First line of defense.
Includes external barricades and internal forces (phagocytes, antimicrobial proteins and attack cells).
Adaptive/Specific Immune System
Gain over time as we encounter pathogens (naturally or premeditated, vaccines). Has memory. Only is activated if the Innate is overwhelmed
Simple Physical Barriers
First Line of defense. Skin, mucus (respiratory, digestive, urinary, reproductive) (Mostly made of mucin). Acids on skin, in stomach and vagina. Enzymes in saliva, mucus and eye fluid. Defensins/antimicrobial proteins in sweat.
Internal innate defenses
Second line of defense. Fevers, chemical signalling, inflammation
Phagocytes (means: to eat):
Neutrophils: eat and self destruct Macrophages (means big eater): monocyte that moves from blood to tissue, some free to patrol, others stationary ex. stellate macrophages in liver, uses cytoplasmic extension to grab and eat/digest then spit out
Natural Killer Cells: Patrols lymph/blood, kills infected/cancerous cells by detecting when a cell stops producing MHC1 protein (major histocompatibility complex) and pokes with enzyme to cause apoptosis
Innate Response
Redness, swelling, pain, heat (for increased metabolic rate of cell repair). Mast cells send out histamines (causes vasodilation of blood vessels, increasing permeability), complement blood proteins, cytokines (signalling cells to travel somewhere)
Release protein rich fluids (swelling) to clot/scab.
Lymphatic system filters fluid and returns it to blood.
Phagocytes and lymphocytes escape capillaries to kill pathogens and clean up dead cells
When overwhelmed, pyrogen released, signals hypothalamus to increase temperature (increase metabolism, Liver/spleen hold on to iron/zinc to prevent bacterial growth)
Trigger adaptive when overwhelmed
Neutrophils
Neutrophils arrive/die first. Triggered when damaged cells release leukocytosis triggering chemicals to release neutrophils from bone marrow.
Endothelial cells send out chemicals to attract neutrophils
Monocytes turn into macrophages to replace neutrophils
Systemic Immune response
Not restricted to specific part of the body, can fight everywhere at once deploying one of both defenses (humoral and cell mediated).
Humoral Immune Response
Dispatches proteins called antibodies. Patrols blood/lymph, combats bacteria in interstitial space
B-Lymphocytes (originate, mature in bone marrow, learn immunocompetence and self tolerance) have over 10,000 membrane bound antibodies (special protein receptors). Each lymphocyte has individual antibodies (for each antigen), colonize lymph nodes move around lymph/blood. Once they find an antigen, they bind and begin to clone. Most are effector cells/active fighters some are memory cells. Effectors have extra ER to create antibodies (2000 per second for 4-5 days). Can also be activated by free floating antigens
Antibody binds to antigen and marks (opsonization), can neutralize (block binding site) and group several (agglutination) making it easier for macrophages. IgE antibodies present in allergic reactions
Also release chemicals to signal phagocytes and lymphocytes
Antigen
Signaling molecules which are not found in the body found on pathogens like bacteria, viruses and fungi. Antibodies attach to antigens
Non-active acquired immunity
Baby receives passive humoral immunity in womb (antibodies through placenta/milk), only temporary.
Can also get temporary immunity (exogenous antibodies) from plasma of donor (ex. Ebola doctors/nurses)
