Reproductive, Endocrine & Urinary System Anatomy Final Study Guide PDF

Ovaries - Functions: ​ Oocyte Production: Production of eggs (oocytes) for fertilization. ​ Hormone Secretion: ○​ Estrogen (E): Supports sexual and reproductive development. ○​ Progesterone (P): Maintains the uterus during pregnancy. Histological Features: ​ Follicles:...

Ovaries - Functions: ​ Oocyte Production: Production of eggs (oocytes) for fertilization. ​ Hormone Secretion: ○​ Estrogen (E): Supports sexual and reproductive development. ○​ Progesterone (P): Maintains the uterus during pregnancy. Histological Features: ​ Follicles: Contain oocytes at various stages of maturation. ​ Interstitial Cells: Secrete hormones (estrogen and progesterone). Support Structures: ​ Ovarian Ligament: Anchors the ovary to the uterus. ​ Suspensory Ligament: Connects the ovary to the pelvic wall. ​ Mesovarium: A fold of the broad ligament that supports the ovary. Uterine Tubes (Fallopian Tubes) - Functions: ​ Oocyte Transport: Transports the oocyte from the ovary to the uterus. ​ Fertilization Site: Typically where fertilization occurs after the oocyte is released from the ovary. Histological Features: ​ Mucosal Layer: ○​ Ciliated Cells: Move the oocyte toward the uterus. ○​ Non-ciliated Cells: Secrete mucus to nourish the oocyte. ​ Muscularis Layer: Two smooth muscle layers that facilitate peristalsis to move the oocyte to the uterus. Uterus - Functions: ​ Protection & Nutritional Support: Provides a safe environment and nourishment for the developing embryo/fetus. ​ Waste Removal: Removes waste produced by the embryo/fetus. Histological Features: ​ Endometrium: Innermost layer where implantation occurs and changes throughout the menstrual cycle. ​ Myometrium: Muscular layer that contracts during labor. ​ Perimetrium: Outer serous layer. Regions: ​ Fundus: The upper portion of the uterus above the fallopian tube openings. ​ Body: Main portion of the uterus where the embryo implants.  ​ Isthmus: The narrow portion connecting the body of the uterus to the cervix. ​ Cervix: Lower portion of the uterus that connects to the vagina. Stabilization: ​ Broad Ligament: Supports the uterus, uterine tubes, and ovaries. ​ Suspensory Ligaments: Three pairs that stabilize the uterus. ​ Pelvic Floor Muscles: Provide additional support to the uterus. Layers of the Uterine Wall - 1.​ Perimetrium: ○​ Structure: Outer serous layer, continuous with the serosa of the uterine tubes and broad ligament. ○​ Function: Provides outer protection and support. 2.​ Myometrium: ○​ Structure: Middle layer composed of three layers of smooth muscle. ○​ Function: Responsible for uterine contractions during labor and menstruation. 3.​ Endometrium: ○​ Structure: Inner glandular layer, site of implantation of the embryo. ○​ Sub-layers: ​ Basal Layer: Connects the endometrium to the myometrium; permanent structure that does not change during the uterine cycle. ​ Functional Layer: Composed of simple columnar epithelium and uterine glands; changes in thickness during the uterine cycle in response to hormones. Changes During the Uterine Cycle ​ Functional Layer: Changes in thickness during the uterine cycle due to hormonal fluctuations (estrogen and progesterone). It thickens in preparation for pregnancy and sheds if implantation does not occur (menstruation). ​ Basal Layer: Remains unchanged throughout the uterine cycle. It serves as a foundation for the regeneration of the functional layer after menstruation Structures Passed by Sperm from Formation to Ejaculation - 1.​ Testes: ○​ Location: Located in the scrotum. ○​ Function: Sperm is produced in the seminiferous tubules of the testes. 2.​ Epididymis: ○​ Location: Located on the posterior side of each testis. ○​ Function: Sperm mature and are stored here for several days. 3.​ Vas Deferens (Ductus Deferens): ○​ Location: Tubes that transport sperm from the epididymis to the ejaculatory ducts. ○​ Function: Transports mature sperm during ejaculation. 4.​ Ejaculatory Ducts: ○​ Location: Formed by the union of the vas deferens and the seminal vesicle ducts.  ○​ Function: Sperm mixes with seminal fluid from the seminal vesicles and passes through the prostate gland. 5.​ Prostate Gland: ○​ Location: Surrounds the urethra just below the bladder. ○​ Function: Adds prostatic fluid to the semen, which helps nourish sperm and protect them from acidity in the vagina. 6.​ Urethra: ○​ Location: Runs through the penis. ○​ Function: Carries semen (which includes sperm) from the ejaculatory ducts to the external opening during ejaculation Cells/Structures That Produce Testosterone - 1.​ Leydig Cells (Interstitial Cells): ○​ Location: Found in the testes, specifically in the interstitial tissue between seminiferous tubules. ○​ Function: Leydig cells are the primary producers of testosterone in males. They respond to luteinizing hormone (LH) from the anterior pituitary to produce and secrete testosterone Urethra - Note differences in the urethra of people assigned female or male at birth Assigned female at birth: ​ Short single segment ​ Epithelium changes from transitional to stratified squamous epithelium Assigned male at birth: ​ 3 segments (prostatic, membranous, and spongy urethra) that are shared with the reproductive tract  ​ Epithelium changes from transitional → pseudostratified columnar → stratified squamous epithelium **Both end at external urethral orifice ​ Internal urethral sphincter ​ External urethral sphincter Organs of the Urinary System (retroperitoneal organs) - Kidneys - monitor and process contents of blood supply to form urine Ureter - collects urine from each kidney and delivers it to the urinary bladder Urinary Bladder - stores urine prior to urination Urethra - urine flows from urinary bladder through urethra to outside of the body retroperitoneal organs: they are located posterior (behind) the peritoneum, and, therefore, they are outside of the peritoneal cavity Structures that Protect the Kidneys - ​ 4 layers of connective tissue ​ Paranephric Fat (adipose tissue provides protection) ​ Renal Fascia (adventitia, deep fascia which anchors the kidney) ​ Perinephric fat (adipose tissue provides protection) ​ Fibrous capsule (dense irregular CT: tightly packed collagen fibers arranged in various directions, providing strength and resistance to stretching) Blood flow through Kidney - 1.​ Abdominal aorta 2.​ Renal artery 3.​ Segmental arteries 4.​ Interlobar arteries 5.​ Arcuate arteries 6.​ Cortical radiate arteries 7.​ Afferent arterioles 8.​ Glomerulus (capillary network for filtration not gas exchange) 9.​ Efferent arterioles 10.​Peritubular capillaries 11.​Cortical radiate veins 12.​Arcuate veins 13.​Interlobar vein 14.​Inferior vena cava Autonomic and Somatic Systems in Urination Process - ​ Storage Phase: Sympathetic system keeps the bladder relaxed and sphincters closed. ​ Voiding Phase: Parasympathetic system contracts the bladder and opens the internal sphincter; somatic control relaxes the external sphincter for urination The Nephron - each kidney has greater than 1 million nephrons Function: site of urine formation Made up of 2 components: Renal Corpuscle: Glomerulus: (capillary network for filtration not gas exchange) the blood vessels of the glomerular capillaries have small fenestrations (holes) in the walls ​ afferent and efferent arteriole entrance/exit Glomerular capsule (Bowmans capsule): pressure within the glomerular capillaries forces fluid and solutes from the blood inside the glomerulus to the hollow space within the glomerular capsule, in a process known as filtration ​ Collects filtrate ​ connects to proximal convoluted tubule Renal Tubule: collects filtrate from corpuscle and empties into collecting system ​ Macula densa cells in the epithelium of renal tubule, monitor and respond to ion concentrations in the filtrate 1.​ Proximal convoluted tubule - simple cuboidal epithelium 2.​ Descending tubule 3.​ Nephron loop 4.​ Ascending tubule 1.​ Distal convoluted tubule - simple cuboidal epithelium --> drains into colleting duct outside of nephron Cortical nephrons: 85% of nephrons, primarily in the cortex of the Kidney, have shorter nephron loop that barely extends into medulla Juxtamedullary nephrons: 15% of nephrons, closer to medulla but still partly in cortex, long nephron loop that extends deep into medulla, plays important role in concentrating urine, vasa recta arterioles ​ Granular or juxtaglomerular cells Collecting System - 1.​ Distal convoluted tubules: drain filtrate into collecting duct, simple cuboidal epithelium 2.​ Collecting ducts: Larger ducts formed by the convergence of convoluted tubules, simple cuboidal epithelium here continue filtration process, simple cuboidal epithelium 3.​ Papillary ducts: Formed by the fusion of collecting ducts near the renal papilla. They drain urine into the minor calyces, simple columnar epithelium 4.​ Minor calyces: Cup-shaped structures that collect urine from the papillary ducts, transitional epithelium 5.​ Major calyces: Formed by the merging of minor calyces, directing urine into the renal pelvis, transitional epithelium 6.​ Renal pelvis: Funnel-shaped structure that collects urine from the major calyces and leads to the ureter, transitional epithelium Production and Filtration of urine - 1.​ Renal corpuscle: ​ The glomerulus is a network of capillaries, and Bowman's capsule is a double-walled structure made of simple squamous epithelium ​ Function: The glomerulus filters blood, allowing water, ions, and small molecules to pass into Bowman's capsule, forming the filtrate 1.​ Proximal Convoluted Tubule: ​ Simple cuboidal epithelium with a dense microvilli that increases surface area ​ Function: Major site for reabsorption of water, glucose, amino acids, and ions (Na+, K+, etc.) back into the blood. Also secretes some substances into the filtrate 1.​ Loop of Helene 2.​ Distal convoluted tubule: ​ Simple cuboidal epithelium with few or no microvilli ​ Function: Further reabsorption of ions (e.g., Na+ and Cl-) and regulation of pH. Also involved in the secretion of some waste products into the filtrate 1.​ Collecting Ducts: ​ Simple columnar epithelium ​ Function: Collects urine from the collecting ducts and drains it into the minor calyces 1.​ Minor Calyx: ​ Transitional epithelium 1.​ Function: Collects urine from the papillary ducts and funnels it into the major calyces 1.​ Major Calyx: ​ Transitional epithelium ​ Function: Directs urine from minor calyces to the renal pelvis 1.​ Renal Pelvis: ​ Transitional epithelium ​ Function: Collects urine from the major calyces and funnels it into the ureter for transport to the bladder Hormones and Their Mechanisms - ​ Hormones are chemical messengers produced by endocrine glands or specialized cells in certain organs. ​ Secreted into the circulatory system → transported to target tissues. How Hormones Cause a Response 1.​ Production & Secretion ○​ Hormones are secreted by endocrine glands (e.g., adrenal medulla, pituitary gland). 2.​ Transport in Circulation ○​ Hormones enter the bloodstream and travel to target cells.  3.​ Receptor Binding ○​ Hormones bind to specific receptor proteins on or in the target cells. 4.​ Signal Activation ○​ Binding activates intracellular signaling molecules. 5.​ Response Generation ○​ Signal molecules alter target proteins → causes physiological responses. Types of Hormones 1.​ Amines ○​ Derived from ammonia. ○​ Example: Epinephrine (adrenal medulla). 2.​ Polypeptides ○​ Short chains of amino acids (100). ○​ Example: Growth Hormone (anterior pituitary). 4.​ Glycoproteins ○​ Proteins with attached carbohydrate groups. ○​ Example: Thyroid Stimulating Hormone (anterior pituitary). 5.​ Steroids ○​ Derived from cholesterol. ○​ Example: Glucocorticoids (adrenal cortex). Key Concept: Endocrine vs. Exocrine Glands ​ Endocrine Glands: Secrete hormones directly into the bloodstream (e.g., pituitary, adrenal). ​ Exocrine Glands: Secrete substances into ducts leading to an external or internal surface (e.g., salivary glands) Endocrine Functions - Hypothalamus: ​ Hormones Produced: TRH (Thyrotropin-Releasing Hormone), CRH (Corticotropin-Releasing Hormone), GnRH (Gonadotropin-Releasing Hormone), etc. ​ Cell Type: Hypothalamic neurons. ​ Stimulus for Release: Changes in homeostasis (e.g., low T3/T4, stress, reproductive needs). ​ Target Cells: Anterior pituitary cells. ​ Typical Response: Stimulates release of TSH, ACTH, FSH, LH, etc., which target endocrine glands throughout the body. Anterior Pituitary (Adenohypophysis):  ​ Hormones Produced: TSH (Thyroid-Stimulating Hormone), ACTH (Adrenocorticotropic Hormone), FSH (Follicle-Stimulating Hormone), GH (Growth Hormone), etc. ​ Cell Type: Specific hormone-producing cells (e.g., thyrotropes, corticotrophs). ​ Stimulus for Release: Releasing hormones from the hypothalamus. ​ Target Cells: Thyroid, adrenal cortex, gonads, etc. ​ Typical Response: ○​ TSH → Thyroid gland: Stimulates release of T3/T4. ○​ ACTH → Adrenal cortex: Stimulates cortisol production. Posterior Pituitary (Neurohypophysis): ​ Hormones Released: Oxytocin, ADH (Antidiuretic Hormone). ​ Cell Type: Produced by hypothalamic neurons; stored and released by posterior pituitary. ​ Stimulus for Release: ○​ Oxytocin: Uterine stretching or breastfeeding. ○​ ADH: High blood osmolarity (dehydration). ​ Target Cells: ○​ Oxytocin → Uterus, mammary glands: Stimulates contractions and milk ejection. ○​ ADH → Kidneys: Increases water reabsorption, raises blood pressure. Thyroid Gland: ​ Hormones Produced: ○​ T3 (Triiodothyronine) and T4 (Thyroxine). ○​ Calcitonin. ​ Cell Type: ○​ T3/T4: Thyroid follicular cells. ○​ Calcitonin: Parafollicular cells. ​ Stimulus for Release: ○​ T3/T4: TSH from anterior pituitary. ○​ Calcitonin: High blood calcium levels. ​ Target Cells: ○​ T3/T4 → Most cells: Increases metabolism, energy use. ○​ Calcitonin → Bones: Inhibits osteoclasts, lowers blood calcium. Parathyroid Gland: ​ Hormone Produced: Parathyroid Hormone (PTH). ​ Cell Type: Chief cells. ​ Stimulus for Release: Low blood calcium levels. ​ Target Cells: ○​ Bones: Stimulates osteoclasts to release calcium. ○​ Kidneys: Enhances calcium reabsorption, stimulates calcitriol production for increased calcium absorption in intestines. Adrenal Glands: Adrenal Cortex (Outer Layer):  ​ Hormones Produced: ○​ Zona Glomerulosa: Mineralocorticoids (e.g., aldosterone). ○​ Zona Fasciculata: Glucocorticoids (e.g., cortisol). ○​ Zona Reticularis: Androgens (small amounts). ​ Stimulus for Release: ○​ Aldosterone: Low blood pressure. ○​ Cortisol: ACTH (from anterior pituitary, triggered by stress). ​ Target Cells and Effects: ○​ Aldosterone → Kidneys: Increases sodium reabsorption, potassium excretion, raises blood volume/pressure. ○​ Cortisol → Most cells: Increases glucose for the brain, reduces inflammation. Adrenal Medulla (Inner Layer): ​ Hormones Produced: Epinephrine and Norepinephrine. ​ Cell Type: Chromaffin cells. ​ Stimulus for Release: Sympathetic nervous system activation (stress response). ​ Target Cells: Most cells. ​ Effect: Increases heart rate, blood pressure, energy availability. Pancreas: ​ Hormones Produced: ○​ Insulin. ○​ Glucagon. ​ Cell Type: ○​ Insulin: Beta cells in islets of Langerhans. ○​ Glucagon: Alpha cells in islets of Langerhans. ​ Stimulus for Release: ○​ Insulin: High blood glucose. ○​ Glucagon: Low blood glucose. ​ Target Cells: ○​ Insulin → Most cells: Decreases blood glucose by promoting uptake and storage. ○​ Glucagon → Liver, adipose tissue: Increases blood glucose by promoting glycogen breakdown and glucose release Hypothalamus-Pituitary Complex - the body’s control center for hormones and automatic body functions. Think of it as a "command hub" that connects your brain and hormone systems to keep everything balanced. How It Works (The 3 Key Jobs): 1.​ Posterior Pituitary (Back Part): ○​ Hormones made in the hypothalamus travel to the posterior pituitary for release. ​ Oxytocin: Helps muscles contract (e.g., during labor or milk ejection).  ​ ADH (Antidiuretic Hormone): Helps kidneys save water and raises blood pressure. 2.​ Anterior Pituitary (Front Part): ○​ The hypothalamus sends special “releasing hormones” to the anterior pituitary through a tiny blood system (hypophyseal portal system). ○​ The anterior pituitary then releases “stimulating hormones” that tell other organs what to do. ​ Example: ​ Hypothalamus sends TRH (Thyrotropin-Releasing Hormone). ​ TRH tells the anterior pituitary to release TSH (Thyroid-Stimulating Hormone). ​ TSH tells the thyroid gland to make its hormones. 3.​ Adrenal Medulla: ○​ The hypothalamus helps control your stress response by telling the adrenal glands to release adrenaline (epinephrine) and noradrenaline (norepinephrine). What’s the Difference Between the Anterior and Posterior Pituitary? Feature Posterior Pituitary Anterior Pituitary Hormones Released Oxytocin, ADH TSH, ACTH, FSH, LH, PRL, GH How It Works Direct release from Controlled by hypothalamus hypothalamus signals Function Example Water balance, contractions Growth, stress, metabolism, reproduction Comparison of the Autonomic Nervous System (ANS) and Endocrine System - Overview ​ Autonomic Nervous System (ANS): A branch of the nervous system that regulates involuntary physiological processes such as heart rate, blood pressure, digestion, and respiratory rate. ​ Endocrine System: A collection of glands that produce hormones, which regulate metabolism, growth, reproduction, and other body functions. Comparison Table Feature Autonomic Nervous System Endocrine System (ANS) Primary Regulates rapid, short-term Regulates slow, long-term processes Function responses (e.g., heart rate, (e.g., growth, reproduction). respiration). Control Electrical impulses via Chemical signals via hormones in the Mechanism neurons. bloodstream. Response Fast (milliseconds to seconds). Slower (minutes to hours). Speed Duration of Short-lived; ends when Long-lasting; persists until hormone is Effect stimulation ceases. metabolized. Mode of Nerve fibers (electrical signals). Bloodstream (chemical messengers). Transmission Target Highly specific; acts on specific Less specific; hormones affect any Specificity organs via neural connections. cell with the correct receptor. Regulation Reflexes and feedback loops Controlled by feedback loops, through sensory and motor primarily involving the hypothalamus pathways. and pituitary gland. Key Sympathetic & Parasympathetic Glands (e.g., thyroid, adrenal, Components divisions, ganglia, and neurons. pancreas) and hormones (e.g., insulin, cortisol). Key Differences ​ Communication Method: ○​ ANS uses electrical signals via neurons. ○​ Endocrine system uses chemical signals (hormones). ​ Response Speed: ○​ ANS is immediate (e.g., fight-or-flight). ○​ Endocrine system takes longer to initiate (e.g., growth hormone effects). ​ Target Specificity: ○​ ANS targets specific organs or tissues. ○​ Endocrine hormones can have widespread effects on multiple systems. Key Similarities ​ Both regulate homeostasis: ANS and endocrine systems work together to maintain internal stability. ​ Both use feedback loops: Ensure proper levels of activity or hormone secretion. ​ Hypothalamus links them: Coordinates neural and endocrine responses (e.g., stress response). Example of Integration ​ Stress Response: ○​ ANS: Sympathetic division triggers rapid heart rate and energy mobilization (fight-or-flight). ○​ Endocrine System: Adrenal glands release cortisol to sustain energy availability over time.