Eye & Endocrine System Sara Abad period-4
Eyeball's Major Structures & Functions
3 Structures: Fibrous, Vascular, Inner Layers
Fibrous: outermost INCLUDES Sclera: protects & shapes providing anchor Cornea: forms window letting light in eye & makes up light bending apparatus
Vascular/ Uvea: middle coat INCLUDES Choroid: absorb light Inner Layer Retina: contains photoreceptors that convert light energy & respond to light Cillary Body: controls lens shape and holds lens providing tension Iris: varies pupil size to focus light
Inner Layers: posterior & anterior of lens INCLUDES Posterior Segment+ Vitreous Humor: gel binding large amounts of water, transmitting light, supporting, & contributing to intraocular pressure Anterior Segment + Aqueous Humor: supplies nutrients and oxygen to lens and cornea while carrying away metabolic wastes
Eye Diseases
Conjunctivitis/ Pink Eye- inflammation of the conjuntiva can lead to infection by bacteria or viruses
Diplopia/ Double Vision- external muscles of two eyes are not perfectly coordinated causing two images instead of one
Glaucoma- too much pressure within the eye compressing the retina and optic nerve eventually leaving to blindness
Cataract- clouding of the lens that causes vision to appear distorted
Myopia/Nearsightedness- distant objects focus infront of the retina instead of on it having blurred vision far away
Hyperopia/ Farsightedness- near objects focus inback of the retina causing near things to be blurry but not farsighted things
Colorblindness- congenital lack of one or more cone pigments
Major Functions of the Endocrine
INFLUENCES METABOLIC ACTIVITY THROUGH HORMONES WHICH xStimulate reproduction xStimulate growth and development xMaintain electrolyte, water, and nutrients in blood xRegulate cellular metabolism & energy balance xMobilizes body defenses
Endocrine Glands & Organs
- produce hormones but lack ducts releasing hormone to nearby tissue fluid INCLUDING: Pineal Gland: secretes Melatonin Hypothalamus Pituitary Gland: secretes Growth Hormone, Thyroid-Stimulating Homrone, Adrenocorticotropic Hormone, Prolactin, Follicle-Stimulating Hormone, Lutenizing Hromone, Antisiuretic Hormone, and Oxytocin Thyroid Gland: secretes Thyroid Hromone & Calcitonin Parathyroid Glands: Parathyroid Hromone Thymus: Thymosin Adrenal Glands: Cortisol, Aldosterone, and Epinephrine & Nonepinephrine Pancreas: Insulin, Glucagon, Gonads: Estrogen, Progesterone, & Testosterone
Hormones
Growth HormoneTargets Liver, Adipose Tissue: affects growth development, stimulates protein production, affects fat distribution
Thyroid Stimulating HormoneTargets Thyroid Gland: regulates secretion of thyroid hormones
Adrenocorticotropic HormoneTargets Adrenal Gland: controls production of sex hormones & production of eggs/ sperm
Prolactin targets Mammary Gland: initiates and maintains milk production in breasts and impacts sex hormone levels
Follicle- Stimulating HormoneTargets Ovary & Testes: controls production of sex hormones & production of sperm and eggs
Luteinizing Hormone Targets Ovary & Testes: controls production of sex hormones & production of eggs and sperm
Antidiuretic Hormone Targets Kidney: regulates water conservation & water in blood
OxytocinTargets Ovary and Testes: stimulates contraction of uterus & milk ducts in the breasts
Thyroid HormoneTargets Thyroid Gland: controls metabolism & affects growth/maturation, nervous system activity
CalcitoninTargets Bones: regulates levels of phosphate in blood
Parathyroid HormoneTargets Kidneys: regulator of blood calcium levels
CortisolTargets Pituitary Gland & Peptide: controls key body functions, anti-inflammatory, maintains blood sugar, muscle strength, regulates salt and water
AldesteroneTargets Kidneys: regulates salt, water,and blood pressure
Epinephrine & NorepinephrineTargets Adrenal Glands: increases heart rate, oxygen intake, and blood flow/ blood pressure
InsulinTargets liver: lowers blood sugar levels
GlucagonTargets liver: raises blood sugar levels
Testosterone Targets Testes: develops and maintains male sexual characteristics and maturation
EstrogenTargets Breasts, Uterus, & Vagina: affects development of female sexual characeristics and reproductive development
ProgesteroneTargets Uterus: stimulates the living uterus for fertilization and prepares breasts for milk production
MelatoninTargets Suprachiasmatic Nucleus: helps with sleep
ThymosinTargets Thymus: stimulates production of T cells for immune system
Endocrine Diseases
Diabetes Insipidus deficiency of ADH causing large amounts of blood glucose to be lost
Diabetes Mellitus results from hyposecretion=type I or hypoactivity=type II of insulin Signs & Symptoms Polyuria: excessive glucose in the blood leads to excessive glucose in kidney filtrate Polydipsia: dehyrdration causing excessive thrist Polyphagia: excessive hunger and food consumption because glucose is there but unobtanable
Hyposecretion of Growth Hormone= pituitary dwarfism Hypersecretion of Growth Hormone= Gigantism
Hypothyroid Disorder Myxedema: includes Goiter if lack of iodine Graves' Disease- autoimmune condition where antibodies are made against thyroid follicular cells continusouly releasing TH