BIO 211 Test 4 Study Guide Flashcards

Urinary System

  • Primary Function: Cleansing the blood and ridding the body of wastes.
  • Secondary Functions:
    • pH regulation
    • Blood pressure regulation
    • Erythrocyte concentration regulation
    • Vitamin D synthesis
  • Urine Characteristics:
    • Color: Generally yellow, varying in degree and clarity.
    • Odor: Freshly voided urine has no particular odor unless affected by certain ingredients; urine that has sat for a long time smells of ammonia.
    • pH: Generally acidic, ranging from 4.5-8.0.
  • Urine Abnormalities:
    • Higher than trace protein levels
    • Pink or red urine (not due to food intake)
    • Blood (except during menstruation)
    • Formed elements of the blood
    • Glucose
    • Nitrites (evidence of infection)
  • Urethra:
    • (Male): Passes through the prostate gland and along the length of the penis; receives semen and other reproductive secretions.
    • (Female): Located inferior to the vaginal wall and clitoris.
  • Urethra Function: Passes urine from the bladder to the outside of the body.
  • Urethra Mucosa: Proximal mucosa is transitional epithelium; distal is stratified squamous.
  • Urethra Differences (Male vs. Female):
    • Length: Male urethra averages 7.5 inches; female urethra is 1.5-2 inches.
  • Urinary Bladder Location:
    • (Female): Anterior to the uterus.
    • (Male): Superior to the prostate.
  • Urinary Bladder Function: Acts as a reservoir (holding ~0.5L) and facilitates expulsion/voiding via the micturition reflex, governed by parasympathetic response.
  • Ureters Location: Between the kidneys and urinary bladder.
  • Ureters Function: Transports urine from the kidney to the bladder.
  • Ureters Structure: Three-layered tube similar to digestive tract organs (mucosa of transitional epithelium, smooth muscle muscularis, and connective tissue).
  • Kidneys Location: Lie between the posterior abdominal wall and the parietal peritoneum; the right kidney sits lower than the left due to the liver.
  • Kidneys Size and Shape: Fist-sized, with a convex and concave border; the hilum is located at the medial concave border.
  • Kidneys Gross Anatomy:
    • Internal:
      • Cortex: Outer layer just deep to the capsule.
      • Medulla: Inner layer, just deep to the cortex.
      • Columns: Off-shoots of the cortex that jut down into the medulla.
      • Pyramids: The structural unit of the medulla.
      • Papilla: Bump at the end of a pyramid.
      • Calyces: Hollow area just after a pyramid.
      • Pelvis: Large hollow area between the calyces and the ureter.
    • Renal Hilum (External): Vessels that exit and enter each kidney at the depression on the concave medial border.
      • Ureter
      • Renal Artery
      • Renal Vein
      • Nerves
      • Lymphatics
  • Nephron: The microscopic functional unit of the kidney.
  • Pathway of Blood Through the Kidneys: Descending Abdominal Aorta → Renal Artery → Segmental Artery → Interlobar Artery → Arcuate Artery → Cortical Radiate (Interlobular) Artery → Afferent Arteriole → Glomerular Capillaries → Efferent Arteriole → Peritubular Capillaries/Vasa Recta → Cortical Radiate (Interlobular) Vein → Arcuate Vein → Interlobar Vein → Renal Vein → Inferior Vena Cava → Right Atrium of Heart
  • Nephron Components:
    • Renal Corpuscle: The filtration unit of the nephron.
      • Bowman’s Capsule: Collects the filtrate.
      • Glomerulus: Blood capillaries.
    • Renal Tubules:
      • Proximal Convoluted Tubule: Receives the filtrate and sends it to the next parts of the tubules.
      • Loop of Henle/Nephron loop
      • Distal Convoluted Tubule
      • Collecting Ducts
  • Juxtaglomerular Apparatus Location: Between the junction of the afferent and efferent arterioles, where the distal convoluted tubule runs between them.
  • Juxtaglomerular Apparatus Function: Monitors stretch on the walls of the arteriole and monitors ion concentration.
  • Four processes for urine formation:
    • Filtration: The process by which the blood running through the kidney has water, ions, wastes, amino acids, sugars, etc. removed from it.
    • Reabsorption: The process by which most of those items that were filtered during filtration are returned to the bloodstream.
    • Concentration: The process by which much of the original filtrate volume that was removed from the blood is reduced down to a concentrated version due to interplay between sodium ions and water.
    • Secretion: The process by which things that were not originally filtered and remained in the blood after filtration takes place, can be removed from the blood and put into the filtrate to be excreted as urine.
  • Filtration Details:
    • Blood runs through the glomerulus, the hydrostatic pressure inside the capillaries causes water and other substances to flow out of the capillaries and into Bowman’s Capsule.
    • The items caught by this capsule are called the “filtrate”.
    • Water, ions, glucose, amino acids, small proteins, vitamins, and wastes are some substances that are filtered.
  • Reabsorption Details: Involves bringing back into the blood of things that were originally filtered out in the renal corpuscle.
  • Concentration Details: Concentrates the filtrate by removal of water, using sodium to create a salty environment that draws water out.
  • Secretion Details:
    • The opposite of reabsorption.
    • Substances that either were not previously filtered and hence remain in the blood, or substances that were filtered, sent out of the filtrate into the surrounding tissue can be put back into the filtrate.
    • Items secreted include Creatinine, Urea, Hydrogen ions, Drugs, Potassium ions.
  • Hormones and Their Function in the Urinary System:
    • ADH (Antidiuretic Hormone):
      • Produced: Hypothalamus, released by the posterior pituitary gland.
      • Conditions Produced: N/A
      • Target Organ: Kidney.
      • Function: Reabsorption of water and reduce urine volume.
    • ANH (Atrial Natriuretic Hormone):
      • Produced: Walls of the right atrium.
      • Conditions Produced: Stretching too much.
      • Target Organ: Heart.
      • Function: Causes sodium and water loss from the kidney to reduce blood volume.
    • Parathyroid Hormone:
      • Produced: Parathyroid.
      • Conditions Produced: Low Calcium.
      • Target Organ: Kidney.
      • Function: Reduce calcium loss.
    • Aldosterone:
      • Produced: Adrenal cortex.
      • Conditions Produced: Low blood volume.
      • Target Organ: Kidney.
      • Function: Regulates sodium and potassium levels in the blood, thereby controlling fluid balance and blood pressure.
  • Role of Kidneys in Vitamin D Synthesis: Vitamin D is produced in the skin but activated in the kidneys.
  • Kidney Response to Low Oxygen: Erythropoiesis acts on the bone marrow to prompt erythrocyte creation.
  • Blood Pressure Regulation by Kidneys: Adjusts ion and water volume concentration; volume adjustments to the blood affect blood pressure.
  • Osmolarity and pH Regulation by Kidneys: Adjustments to ion retention or excretion such as sodium and potassium, and hydrogen and bicarbonate, affect fluid concentration and pH.

Male Reproductive System

  • Essential Organ (Gonad): Testes.
  • Series of Ducts: Seminiferous tubules, Epididymis, Vas (Ductus) Deferens, Ejaculatory Duct, Urethra.
  • Glands: Seminal Vesicles, Prostate Gland, Bulbourethral (Cowper’s) Gland.
  • Supporting Structures: Penis, Scrotum, Spermatic cords.
  • Functions: Sperm production, Maturation of sperm, Androgen production, Transfer of sperm to female reproductive tract.
  • Testes Location: Sac external to the body called the scrotum.
  • Reason for External Location: Temperature regulation; testes need to be 2-4°C lower than normal body temperature.
  • Connection to Body: Spermatic cord.
  • Contents of Spermatic Cords: Testicular artery, testicular vein, vas deferens, lymphatic vessels, and nerves.
  • Testes Function: Sperm and testosterone production.
  • Meiosis Location: Seminiferous tubules.
  • Process of Spermatogenesis: Spermatogonia to full spermatozoa.
  • Sperm Cell Parts: Head, midpiece, tail.
  • Acrosome Location: Head.
  • Acrosome Function: Contains Enzymes that help the sperm penetrate.
  • Midpiece Function: Contains many mitochondria to produce energy.
  • Tail Function: To propel.
  • Pathway of Sperm: Seminiferous tubules → Epididymis → Vas Deferens → Ejaculatory Duct
  • Epididymis: C-shaped tube on the inferior-posterior edge of the testes.
  • Vas Deferens: Leads from the epididymis to the prostate gland.
  • Seminal Vesicles: Secrete 60% of semen, adding fructose to seminal fluid.
  • Prostate Gland: Secretes 30% of semen and adds alkaline fluid to seminal fluid.
  • Reason for Alkaline Seminal Fluid: To raise the acidic pH found in the vaginal tract and helps to coagulate semen, and then de-coagulate it.
  • Cowper’s Glands (Bulbourethral): Secrete 5% of semen and produce a thick, salty fluid.
  • Function of Thick, Salty Fluid: Cleanses the male urethra after arousal and before ejaculation.
  • Penis: Male organ used to transfer sperm into the female.
  • Leydig cells: Produce testosterone in males
  • Functions of Testosterone: Promotes spermatogenesis, muscle development, bone growth, development of secondary sex characteristics (thyroid cartilage enlargement, voice deepening, body hair growth…) and maintains sex drive.

Female Reproductive System

  • Essential Organ (Gonad): Ovaries.
  • Series of Ducts: Vagina, uterus, and fallopian (uterine) tubes.
  • Glands: Mammary glands and Bartholin’s glands.
  • Supporting Structures: Vulva consisting of labia, the mons pubis, and the clitoris.
  • Functions: Oocyte production (Egg), Oocyte expulsion, Androgen production, Receive sperm from the male tract, Provide a place for fertilization, Provide a place for embryo and fetus development, Nourish the baby upon birth.
  • Vulva Structures:
    • Mons pubis: Fat pad covered with hair over the pubic bone.
    • Labia majora: Hair-covered skin posterior and inferior to the mons pubis.
    • Labia minora: Thinner, pigmented skin folds internal to the majora.
    • Clitoris: Nerve body originating from the same cells as the glans penis.
    • Hymen: Thin partial membrane covering the vaginal entrance.
    • Bartholin’s glands: Also called Greater Vestibular Glands, just deep to the labia minora.
  • Vagina Description:
    • Smooth muscle canal and the beginning of the female reproductive tract.
    • Entrance for the penis and the exit for menstruation and childbirth.
    • Lined with mucosa that creates folds called rugae.
    • The Bartholin’s glands and a pair of lesser vestibular glands lubricate the vagina to keep it moist.
    • Bacteria in the vagina keep its pH acidic.
  • Function of Bartholin’s Glands: Lubrication.
  • Primary Oocytes Formation: Primary oocytes will undergo meiosis to form gametes but are halted in Meiosis I until puberty when meiosis resumes. Each time a woman is nearing the middle of the ovarian cycle, meiosis will progress until Metaphase II and then halt, waiting to be fertilized. Primary oocytes undergo atresia (wasting) throughout a woman’s reproductive life from 1-2 million at birth to 400,000 at puberty to nearly zero at the end of menopause.
  • Fertilized Egg: Zygote.
  • Hormonal Control During Follicular Phase: GnRH from the hypothalamus stimulates the release of FSH and LH from the anterior pituitary gland.
  • Function of FSH and LH During Follicular Phase: Stimulates the follicles to grow while LH stimulates the theca cells of the follicle to produce estrogen.
  • Follicular Phase Regulation: Negative feedback.
  • Ovulation: Expulsion of the mature oocyte/ovum.
  • Ovulation Regulation: Positive feedback.
  • Ovulation Day: Day 14 in a typical 28-day ovarian cycle.
  • Ruptured Follicle in Luteal Phase: Becomes the corpus luteum.
  • Hormone Produced by Corpus Luteum: Progesterone.
  • Fate of Corpus Luteum If No Fertilization: Degenerates into a corpus albicans.
  • Divisions of Uterine Tubes: Isthmus, ampulla, infundibulum.
  • Function of Uterine/Fallopian Tubes: Conduct the oocyte from the ovary to the uterus.
  • Fimbriae: Finger-like projections flaring from the infundibulum.
  • Location of Uterine/Fallopian Tubes: Posterior abdominal wall.
  • Layers of the Uterus (Uterine Wall/Interior):
    1. Perimetrium
    2. Myometrium
    3. Endometrium
  • Divisions of the Uterus (External):
    1. Fundus
    2. Body
    3. Cervix
  • Effect of Estrogen on Endometrium: Growth.
  • Effect of Progesterone on Endometrium: Maintains it.
  • Part of Endometrium Shed During Menses: Functionalis.
  • Phases of Menstrual Cycle: Menses phase, proliferative phase, and secretory phase.
  • Menses Phase: The lining is shed; declining progesterone levels, caused by the degeneration of the corpus luteum into the corpus albicans in the ovaries, bring on the shedding (Estrogen levels decline).
  • Proliferative Phase: Estrogen levels increase and the lining builds again.
  • Secretory Phase: The uterine lining is maintained while glands in the functionalis secrete glycogen-rich fluid that will nourish the zygote if fertilization has taken place and it implants.
  • Function of Mammary Gland: Lactation.
  • Lactation: Breast milk production.
  • Onset of Puberty: About age 8 or 9, the hypothalamus begins to release Gonadotropin Releasing Hormone (GnRH). It prompts the Anterior Pituitary Gland to release Luteinizing Hormone (LH) and Follicle Stimulating Hormone (FSH) in both genders.
  • Menopause: Reduced levels of estrogen and progesterone.

Endocrine System

  • Comparison with the Nervous System: N/A
  • Endocrine Organs and Locations:
    • Hypothalamus
    • Pituitary Gland - sella turcica of the sphenoid
    • Pineal Gland - epithalamus near the center of the brain
    • Thyroid Gland - front of your neck
    • Adrenal Gland - top of each of your kidneys
    • Gonads
  • Classes of Hormones:
    • Steroid Hormones
    • NonSteroid Hormones (= Protein and Peptide and amine hormones)
  • Hormone Specificity: Hormones bind only to specific cells (target cells/organs) due to receptors.
  • Up-regulation and Down-regulation: Processes that target cells use to adjust their sensitivity to hormones by changing the number of receptors they have for that specific hormone.
  • Hormone Release Control: Negative feedback systems.
  • Stimuli of Hormone Release:
    • Humoral Stimuli: Changing blood levels of ions and nutrients directly stimulates secretion of hormones.
    • Neural stimuli: Nerve fibers stimulate hormone release.
    • Hormonal stimuli: Hormones stimulate other endocrine organs to release their hormones.
  • Hypothalamus Control of Pituitary Gland: It secretes releasing and inhibiting hormones that direct the actions of the anterior pituitary gland.
  • Hormones Produced in Hypothalamus: Oxytocin and Anti-Diuretic Hormone.
  • Posterior Pituitary Gland Hormones: Does not produce any of its own hormones and only stores two hormones produced by the hypothalamus.
  • Anterior Pituitary Gland Hormones:
    • Growth Hormone: Bone and muscle growth.
    • Prolactin: Lactation.
    • Thyroid Stimulating Hormone (Thyrotropin): Causes the release of Thyroid hormone.
    • Adrenocorticotropic Hormone (Corticotropin): Targets cells in the adrenal cortex, Stimulates the adrenal cortex to release cortisol (glucocorticoid).
    • Follicle Stimulating Hormone: Sperm/egg production/ follicle growth.
    • Luteinizing Hormone: Testostrone production, Ovulation.
    • Melanocyte-stimulating hormone: Produces melanin.
  • Tropic Hormones: Hormones that stimulate other endocrine glands to secrete their own hormones (e.g., Follicle-Stimulating Hormone, Thyroid stimulating hormone).
  • Thyroid Hormones:
    • T3 – Triiodothyronine
    • T4 – Thyroxine
    • Calcitonin
  • Parathyroid Gland Hormone: Parathyroid hormone which raises blood calcium levels. Target cells for PTH: Bones, Kidneys, Intestines
  • Adrenal Cortex Hormones: Mineralocorticoids, glucocorticoids, gonadocorticoids.
  • Adrenal Medulla Hormones: Epinephrine, norepinephrine
  • Pancreas Functions: Exocrine Function: Digestion, Endocrine Function: Hormone Production
  • Pancreas Hormones:
    • Alpha (α) cells: Secrete glucagon. Glucagon acts to increase blood glucose levels.
    • Beta (β) cells: Secrete insulin. Insulin acts to decrease blood glucose levels.
  • Ovary Hormones:
    • Estrogen (Menstrual cycle).
    • Progesterone (Prepares the uterine lining for implantation of a fertilized egg and helps maintain pregnancy. Inhibits uterine contractions during pregnancy).
  • Testes Hormone: Testosterone
  • Placenta Hormone: Human Chorionic Gonadotropin (hCG): continues producing progesterone and estrogen during pregnancy. This prevents menstruation
  • Heart Hormone: Atrial Natriuretic Peptide (ANP) promotes sodium, and hence water loss from the kidney
  • Gastric Mucosa of the Stomach Hormone: N/A
  • Intestinal Mucosa of the Small Intestines Hormone: Digestive hormones
    * Gastrin
    * Secretin
    * Cholecystokinin
  • Thymus Hormones: Thymosin-Involved in the normal development of T-lymphocytes or ‘T-cells’