TTU ZOOL 2403 Final Exam Dr. Boros fully solved & updated

What does the Kidney do? - answer-Produces Urine Functions of Kidney - answer-1. Excretion -removal of wastes from body fluids into urine 2. Regulation of Blood -Ions a. control blood Na+ (sodium), K+ (potassium), and Cl- (chloride) levels -ph a. control blood H+ (hydrogen) and HCO3- (bicarbonate) levels -Pressure and Volume a. control blood fluid volume and therefore blood pressure What three processes do the Kidneys use to perform their functions? - answer--Filtration of water, ions, nutrients, and waste products from the blood -Reabsorption of most of the water, ions, and nutrients back into the blood -Excretion of metabolic wastes into the urine Describe the Drinking Process - answer-Water is absorbed by the gastrointestinal (GI) tract into the blood, which goes to the Renal Arteries which supply the kidneys and then becomes urine. We lose water constantly through our... - answer--Skin -Lungs -Digestive System The kidneys can regulate what because of what? - answer-They can regulate water volume because they can concentrate or dilute the urine Among other things, what are the kidneys responsible for? - answer-The kidneys are responsible for our ability to survive on land without dehydrating Where are the kidneys located and what are they protected by? - answer-The Kidneys are located on either side of the . vertebral column and are partly protected by the ribcage What are the 2 divisions of the kidney? - answer-The Renal Cortex and the Renal Medulla Describe the Renal Cortex - answer-The Renal Cortex is the outer portion of the kidney Describe the Renal Medulla - answer-1. inner portion of the kidney 2. separated into renal pyramids by renal columns How is blood supplied to the kidneys? - answer-1. Each Kidney receives blood from a Renal Artery 2. The Renal Artery Branches into many smaller and smaller arteries 3. These smaller arteries travel between renal pyramids within the Renal Columns 4. They ultimately deliver the blood via the arterioles to a capillary network called the "Glomerulus" What is the percentage of total cardiac output that kidneys receive? - answer-20-25% How many liters of blood flow through the kidneys each minute? - answer-1.2 Liters How many times a day is the entire blood volume filtered by the kidneys? - answer-60 times How long would it take for the blood filtered by the kidneys to be excreted if it were excreted in its entirety? - answer-25 minutes What percentage of the filtered blood is returned to the cardiovascular system? - answer-99% Composition of the Kidneys - answer-1. Nephrons 2. A Collecting System How many nephrons does the kidney contain? - answer-The kidney contains about 1.25 million nephrons which are 85 miles in combined length What is the Nephron? - answer-The Nephron is the functional unit of the Kidney Composition of the Nephron - answer-1. Renal Corpuscle 2. Renal Tubule Where does Urine Production begin? - answer-In the Nephron What occurs in the Nephron? - answer-1. Blood is filtered into the Nephron 2. Composition changes during the process Composition of the Renal Corpuscle - answer-1. Glomerulus 2. Bowman's Capsule 3. Urinary Space What does the Glomerulus intertwine with? - answer-The network of capillaries Where does the glomerulus receive blood and where does blood leave the glomerulus? - answer-The glomerulus receives blood from the afferent arteriole and blood leaves the glomerulus through the efferent arteriole What is the Bowman's Capsule? - answer-A sac-like structure that surrounds the glomerulus What is the Bowman's capsule composed of? - answer-Squamous Epithelial Cells What does the Bowman's Capsule enclose? - answer-the Urinary Space Define Urinary Space - answer-The space between the inner layer lining of the glomerulus and the outer layer of the Bowman's capsule Where does Filtration of fluid from Blood into the Nephron occur? - answer-In the Renal Corpuscle Describe Filtration of fluid from Blood into the Nephron - answer-Blood Pressure 1. forces water and dissolved solutes out of the glomerulus and into the urinary space 2. produces a protein-free solution called filtrate What are the 3 Layers of Filtration? - answer-1. The glomerulus (capillary): endothelial cell layer 2. Middle connective tissue layer 3. Inner lining of the Bowman's capsule: epithelial cell layer What is the Glomerular Endothelial Layer? - answer-Pores in the endothelial cells lining the glomerular capillaries Function of the Glomerular Endothelial Layer - answer-They are small enough to prevent passages of the blood cells into the filtrate, but they do allow some proteins to get through Composition of the Podocyte Layer of the Inner Lining of the Bowman's Capsule - answer-It is made up of epithelial cells, "foot cells", called podocytes. What are Podocytes composed of? - answer-They're composed of many foot processes called pedicels Describe the role of the Podocyte Layer of the Inner Lining of the Bowman's Capsule - answer-There are filtration slits between adjacent pedicels of podocyte which are smaller than the pores of the endothelial cells. They only allow water and dissolved solutes from the blood and into the urinary space. What causes kidney disease and kidney failure? - answer-The connective tissue layer between the pores and slits can become clogged with debris What is the Renal Tubule? - answer-A long, U-shaped tube extending from the cortex into the medulla and back into the cortex Where does the Renal Tubule begin? - answer-The Renal Corpuscle Composition of Renal Tubule - answer-1. Proximal Convoluted Tubule (PCT) 2. Loop of Henle 3. Distal Convoluted Tubule (DCT) Where does the Renal Tubule end? - answer-The collecting duct Composition of the Wall of the Tubule - answer--The wall of the Renal Tubule is composed of epithelial cells -They can be anything form squamous to columnar cells What determines the type of epithelial cell that lines the Renal Tubule? - answer-The degree of activity of that portion of the tubule Functions of the Renal Tubule cells - answer-1. Reabsorb nutrients and water form the filtrate 2. Return said nutrients and water to the blood 3. Excrete what's left in the tubule into the urine What happens to the filtrate traveling along the tubule? - answer-The composition of the filtrate changes How do the reabsorbed water and solutes return to the blood? - answer--Peritubular Capillaries and Vasa Recta Describe the Peritubular Capillaries and the Vasa Recta - answer--Both are branches of the efferent arteriole -They drain blood into the venous system and back into the heart Proximal Convoluted Tubule - answer-The first segment of the renal tubule What occurs in the Proximal Convoluted Tubule? - answer-Bulk reabsorption of filtrate What percentage of the filtrate is reabsorbed in the PCT? - answer-60-70% What do the epithelial cells have in the PCT and what purpose do they serve? - answer-Epithelial cells have microvilli to increase surface area for absorption Loop of Henle - answer-The middle segment of the renal tubule What is the Loop of Henle composed of and what occurs? - answer-Composed of: -a descending limb where fluid flows "down" into the medulla -an ascending limb where fluid flows "back up" into the cortex How does the Loop of Henle concentrate urine? - answer-1. Na+ and Cl- are actively pumped out of the ascending limb and back into the bloodstream 2. Water follows out of the descending limb and back into the bloodstream 3. Tubular fluid becomes very concentrated 4. Urea (the most abundant organic waste from amino acid breakdown) is now the main solute left in the tubular fluid, hence urine Distal Convoluted Tube - answer-The last segment of the renal tubule Describe the epithelial cells lining the DCT - answer-1. They're smaller than those of the PCT and do not have microvilli 2. They're less active than the cell of the PCT 3. These cells are more highly specialized than the cells of the PCT What occurs in the DCT and why? - answer--Further adjustments are to the filtrate are made -Very selective reabsorption occurs here in response to hormones What is the purpose of selective reabsorption in the DCT? - answer-To regulate: -blood pressure and volume -blood ph What type of structure is the Juxtaglomerular Apparatus? - answer-Endocrine Composition of Juxtaglomerular Apparatus - answer--Macula densa -Juxtaglomerular (JG) cells Macula Densa - answer-specialized epithelial cells in the DCT Juxtaglomerular (JG) cells - answer-specialized smooth muscle cells of the afferent arteriole What do the JG cells sense? - answer-Decreased blood pressure What happens when JG cells sense decreased blood pressure? - answer-JG cells release renin (a hormone) What does renin activate? - answer-Renin activates angiotensin (another hormone) What does angiotensin cause? - answer--Vasoconstriction -Secretion of aldosterone by the adrenal cortex What does aldosterone cause? - answer-It causes DCT cells to increase Na+ reabsorption (water always follows Na+) What happens to the Na+ and water? What does it result in? - answer-Both are returned to the blood, which results in increased blood pressure and increased volume What do stretch receptors of the heart walls sense? - answer-Increased blood pressure or volume What happens when the stretch receptors of the heart wall sense increased blood pressure? - answer-The atria of the heart releases Atrial Natriuretic Peptide (ANP) What does the release of ANP cause? - answer-Decrease in Na+ and water reabsorption at the DCT so there is increased Na+ and water excretion into the urine What does the release of ANP result in? - answer-Decreased blood pressure and volume What does decreased blood pressure lead to? - answer--The release of Renin which releases Angiotensin which releases Aldosterone which leads to: 1. increased Na+ and water reabsorption at DCT 2. increased blood volume and therefore pressure -Less water in the urine -Urine becomes more concentrated What does increased blood pressure lead to? - answer--The release of Atrial Natriuretic Peptide (ANP) which leads to 1. decreased Na+ and water reabsorption at DCT 2. decreased blood volume and therefore pressure -More water in the urine -Urine becomes dilute How does the DCT regulate blood pH? - answer--H+ excretion into the forming urine - HCO3- (bicarbonate) production and reabsorption into the blood What is the function of HCO3? - answer-HCO3 buffers the blood What does the Collecting Duct determine? - answer-The final composition and volume of urine Hypothalamic neurons are stimulated by either... - answer-1. decreased blood pressure or... 2. increased blood Na+/Cl- concentration Which hormone do the Hypothalamic neurons release and what does that hormone cause? - answer-Hypothalamic neurons release Antidiuretic Hormone (ADH) and causes increased water reabsorption at the Collecting Duct What do collecting ducts form when they converge? - answer-Collecting ducts converge to empty into a minor calyx Where does the minor calyx end? - answer-The minor calyx ends at the renal papilla of each renal pyramid Minor Calyx - answer--cup like structure surrounding each renal pyramid -collects urine from each renal pyramid -several join to form a major calyx Major Calyx - answer--collects urine from several minor calyces -join to form the Renal Pelvis Renal Pelvis - answer--acts as a funnel to drain urine from the kidney to the ureter What type of muscle makes up the Ureters? - answer-Smooth muscle Function of the Ureter - answer--transports urine towards the urinary bladder -collects urine from the renal pelvis -empties urine into the urinary bladder -prevents the back-flow of urine How do the Ureters prevent the back-flow of urine? - answer-THey flatten as the bladder fills with urine and when the bladder contracts to void the urine Urinary Bladder - answer--hollow, muscular organ (smooth muscle) -temporary reservoir for urine storage How much urine can the urinary bladder hold to be full? - answer-1 liter Urothelium - answer--lines the urinary bladder -also known as transitional epithelium Composition of the Urothelium - answer-Composed of cells that: 1. are impermeable to water 2. can rearrange themselves and spread out as the bladder fills with urine How long is the male urethra? - answer-7-8 inches long Where does the male urethra begin? - answer-Begins at the inferior pole of the bladder What does the male urethra pass through? - answer-The prostate gland and the penis How long is the female urethra? - answer-1-2 inches long What does the shortness of the female urethra leave a female more prone to? - answer-Females are more prone to frequent infection of the urinary bladder External Urethral Sphincter - answer-Skeletal muscle that surrounds the urethra in both sexes Describe the function of the External Urethral Sphincter - answer-It's a voluntary muscle, so it's under conscious control. -Relaxation permits micturition (urination) Components of the Female Reproductive System - answer--Ovaries -Uterine tubes -Uterus -Vagina -External Genitalia -Labia -Minora -Majora Ovaries - answer-small, almond-shaped organs Composition of Ovaries - answer--an outer cortex which contains follicles -an inner medulla which contains blood vessels Function of Ovaries - answer--produces female gametes: oocytes -Secretes female sex hormones: estrogen and progesterone Composition of Follicles - answer--a female germ cell oocyte -an epithelium layer that surrounds the oocyte What determines the type and function of the epithelium? - answer-Development Where does Oogenesis begin? - answer-It begins from stem cells called Oogonia Oogonia goes through what to produce what? - answer-Oogonia undergo mitosis to produce oocytes before birth Composition of Primordial Follicles - answer--Oocyte -Simple squamous epithelium surrounding the oocyte During what time period do the ovaries only contain primordial follicles? - answer-From birth until puberty When do primordial follicles mature into primary follicles? - answer-At puberty and each month What hormone stimulates the maturation of primordial follicles? - answer-Follicle Stimulating Hormone (FSH) Function of Primary Follicle Epithelial Cells - answer--they enlarge -divide to form a stratified epithelium -begin to produce estrogen Granulosa Cells - answer-another name for Primary Follicle Epithelial Cells Secondary Follicles - answer-Primary Follicles that have matured Function of Secondary Follicle Epithelial Cells - answer--continue to produce estrogen -begin to secrete fluid which accumulates in many small cavities between epithelial cells How many of the maturing follicles develops into a bigger tertiary follicle each month? - answer-1 out of 12 What happens to the rest of the follicles that don't develop into a tertiary follicle? - answer-The rest atrophy and degenerate Antrum - answer-A large cavity of fluid made from smaller cavities between the epithelial cells that have fused together What do the oocytes do in the antrum? - answer-1. bulge into the antrum 2. separates from the follicles 3. floats free in the antrum Function of Tertiary Follicle Epithelial Cells - answer-Produce a lot of estrogen, which leads to an estrogen surge What does an estrogen surge lead to? - answer-A Lutenizing Hormone (LH) Surge What does an LH surge lead to? - answer-Ovulation Ovulation - answer-The release of oocytes from this follicle Corpus Luteum - answer-The empty tertiary follicle is transformed into this The epithelial cells of the Corpus Luteum produce what? - answer-Progesterone Progesterone prepares what for what? - answer-Prepares uterine lining for pregnancy What happens to the Corpus Luteum if fertilization doesn't occur? - answer-It degenerates, fills with scar tissue, and becomes the Corpus Albicans When does the Corpus Luteum degenerate? - answer-12 days after ovulation Follicle maturation - answer-Stimulated by FSH What does LH stimulate? - answer--ovulation -corpus luteum formation Follicular Phase of Ovarian Cycle - answer--Primordial through Tertiary Follicles -Stimulated by Follicle Stimulating Hormone (FSH) -Estrogen is the primary sex hormone produced by the ovaries during this phase Luteal Phase of the Ovarian Cycle - answer--Corpus Luteum and Albicans formation -associated with Lutenizing Hormone (LH) -Progesterone is the primary sex hormone produced by the ovaries during this phase Fallopian Tubes/Oviducts - answer-Other names for Uterine Tubes Describe Uterine Tubes - answer-Hollow, muscular tubes Function of the Uterine Tubes - answer-Transport oocyte from ovary to uterus How long does oocyte transport take? - answer-3-4 days Where does fertilization occur? - answer-Occurs in the uterine tube near its entrance into the uterus What happens to unfertilized oocytes? - answer-They degenerate Components of the Uterus - answer-1. Body -Largest portion of the uterus 2. Cervix ("neck") -distal end projecting into the vagina What does the uterus provide? - answer-Protection, nutrition and waste removal for a developing fetus The 3 layers of the Uterine Wall - answer-Perimetrium, Myometrium, Endometrium Perimetrium - answer--outer layer of uterine wall -made of epithelium and connective tissue -continuation of a broad ligament Myometrium - answer--very thick; smooth muscle layer -middle layer of uterine wall -provides the force to move the fetus out of the uterus and into the vagina Endometrium - answer--inner glandular and vascular layer -supports the growing fetus (becomes mother's portion of the placenta) What happens in the Endometrium? - answer-Estrogen and Progesterone produced form the ovary cause the glands and blood vessels of the endometrium to develop and grow each month What happens if the oocyte is not fertilized? - answer-Part of it is sloughed Uterine Cycle (a.k.a. Menstrual Cycle) - answer-A repeating series of changes in the endometrium How long does the Uterine Cycle last? - answer--Lasts 21-35 days -On average 28 days 3 Phases of the Ovarian Cycle - answer-Menses, Proliferative, Secretory Menses - answer-The destruction of the superficial layer of the endometrium What does menses result in? - answer-Release of blood and tissue What stimulates menses? - answer-Decrease in progesterone How long does endometrial sloughing last? - answer-1-7 days How much blood is shed during endometrial sloughing? - answer-35-50 ml What happens to the deeper portion of the endometrium? - answer-Remains to regrow the superficial portion of the endometrium for the next uterine cycle Proliferative Phase - answer--Follows menses -Results in repair and regeneration of the endometrium What is the Proliferative Phase stimulated by? - answer-Estrogen secreted by the ovarian follicles Secretory Phase - answer-Results in secretion by the glands and rapid growth of the arteries When does the Secretory Phase begin? - answer-At ovulation What is the Secretory Phase stimulated by? - answer-Progesterone secreted by the ovarian corpus luteum, persisting as long as the corpus luteum does What do the secretions in the Secretory Phase prepare for? - answer-Implantation of the embryo - the secretions will provide it nourishment - the vessels will provide blood and Oxygen How long foes the Secretory Phase last? - answer-12 days if fertilization does not occur Describe the relationship between Uterine and Ovarian Cycles - answer--Menses and the Proliferative Phase occur in the Follicular Phase of the Ovarian Cycle -Secretory Phase occurs during Luteal Phase of the Ovarian Cycle The Vagina - answer--An elastic, muscular tube -Extends from the cervix to the vestibule Location of the Vagina - answer-Between the urethra, and the rectum and anus Function of the Vagina - answer--Passageway for menstrual fluids, spermatozoa -Birth Canal Clitoris - answer-Erectile tissue (a plexus of veins) Labia Majora - answer--Contains adipose tissue -Protects inner structures -Covered with pubic hair Labia Minora - answer--Medial to the Labia Majora -Not covered with pubic hair Vestibule - answer--Space between the 2 labia minora -Contains openings for the Urethra and the Vagina Location of the Mammory Glands - answer-They lie in pectoral fat pads deep to the skin of the chest Composition of Mammory Glands - answer-Composed of Lobes, each containing several secretory lobules which drain their secretory product (milk) into lactiferous ducts Nipple - answer-contains the openings of the lactiferous ducts Areola - answer-Reddish-brown skin around the nipple Function of the Mammory glands - answer-Secretes milk to nourish an infant (lactation) -controlled by oxytocin Parasympathetic Activation in the Female Sexual Response - answer-Leads to: -engorgement of the erectile tissue of the clitoris -increased secretion of the mucus glands in the cervix and vestibule Female Orgasm - answer-Accompanied by: -peristaltic contractions of smooth muscle in the uterus and vagina due to sympathetic action -rhythmic contractions of skeletal muscles surrounding the clitoris due to somatomotor activation Components of the Male Reproductive System - answer--Testes -Duct System -Glands -External Genitalia Function of the Testes - answer-Produce the sperm portion of the semen Function of the Duct System - answer-Transport the semen Function of the Glands - answer-Produces the Fluid portion of the semen External Genitalia - answer-Penis Scrotum Function of the Penis - answer-Releases semen Describe the Testes - answer--egg shaped structures suspended in the scrotum -contains seminiferous tubules where sperm are produced How long are the tightly coiled seminiferous tubules on each side? - answer-1/2 a mile Contents of the Seminiferous Tubules - answer--Spermatogonia -Sperm -Sertoli cells -Leydig cells Spermatogenesis - answer-The continuous process of sperm production When does spermatogenesis begin and how long does it continue? - answer-Begins at puberty and continues past age 70 Where does spermatogenesis begin? - answer-begins at the outermost cell layer in seminiferous tubules and then proceeds towards the lumen Where are sperm released into? - answer-The lumen Spermatogenesis: Step 1 - answer-Spermatogonia, sperm stem cells, undergo mitosis and become Spermocytes Spermatogenesis: Step 2 - answer-Spermocytes undergo meiosis and become Spermatids Spermatogenesis: Step 3 - answer-Spermatids undergo physical maturation and become Spermatozoa Spermatogenesis: Step 4 - answer-Spermatozoa lose contact with the wall of the seminiferous tubule and enter the lumen When does a spermatozoa enter the lumen? - answer-about 9 weeks after it was generated by a spermatogonium What does the head of a sperm contain? - answer--contains nucleus which carries chromosomes -all other organelles are lost, NO energy reserves -must absorb nutrients from the surrounding fluid What is the tip of the head of the sperm covered with? - answer-an acrosomal cap essential for fertilization Sertoli cells - answer-are supporting cells Functions of the sertoli cells - answer-1. support spermatogenesis by nurturing the developing sperm 2. Maintains blood-testis barrier How do sertoli cells nurture developing sperm? - answer-They provide nutrients and chemical stimuli for development What are sertoli cells stimulated by? - answer-FSH and Testosterone Location of Leydig Cells - answer-in the connective tissue surrounding the seminiferous tubules What stimulates Leydig cells and what is produced? - answer-LH stimulates Leydig cells to produce testosterone What is the most important androgen? - answer-Testosterone Functions of Testosterone - answer-1. stimulates spermatogenesis 2. promotes libido (sex drive) 3. establishes secondary male sex characteristics such as distribution of facial hair and increased muscle mass and body size 4. Maintains the gland and organ of male reproductive tract Semen - answer-Sperm + Fluids What delivers Semen? - answer-The duct system Pathway of Spermatozoa - answer--Epididymis -Ductus deferens -Ejaculatory Duct -Urethra -Prostate Gland portion -Penis Portion The Epididymis - answer--A coiled tube about 7 m long -First part of the duct system next to the testes Function of the Epididymis - answer--Primary storage of sperms -Protects sperms -recycles damaged spermatozoa Sperm leaving the epididymis are still what? - answer-Immobile Ductus Deferens - answer-The second part of the duct system begins at the tail of the epididymis about 18 inches long How long can the Ductus Deferens store sperm? In what state? - answer-Ductus Deferens can store sperms for several months in a state of suspended animation (low metabolic rates) What kind of muscle does the Ductus Deferens contain? - answer-Contains smooth muscle What happens when muscles contract in the Ductus Deferens? - answer-Muscular contraction propels semen What do the Ductus Deferens travel through? As part of what? - answer-Travels through the inguinal canal as part of the spermatic cord What does the inguinal ligament form? - answer-The inguinal canal Inguinal Canal - answer-A passageway out the anterior abdominal wall, through which the spermatic cord must pass What forms the Ejaculatory Duct? - answer-The joining of the Ductus Deferens and the duct of the Seminal Vesicle How long is the Ejaculatory Duct? - answer-2 cm long What does the Ejaculatory Duct travel through? - answer-The Prostate Gland Where does the Ejaculatory duct empty into? - answer-The urethra What does the first part of the Male Urethra travel through? - answer-The Prostate Gland What does the Prostate gland secrete into the Urethra? - answer-Prostate Fluids What does most of the male urethra travel through? - answer-Through the penis Glands produce what? - answer-The fluid portion of the semen What are the Glands of the reproductive system? - answer-1. Seminal Vesicles 2. Prostate Gland 3. Bulbourethral glands What percentage of semen volume do the seminal vesicles produce? - answer-about 60% What do semen fluids contain? - answer-1. Fructose 2. Prostaglandins 3. Fibrinogen What purpose does the Fructose serve? - answer-Fructose provides energy for sperm What purpose do the Prostaglandins serve? - answer-They stimulate smooth muscle contractions in both the male and female What purpose does the Fibrinogen serve? - answer-Fibrinogen forms temporary clot in the vagina What is a typical Ejaculation release? - answer-- 2-5 ml of semen - 20-100 million spermatozoa What do the fluids of the semen activate? - answer-The immobile sperm Location of the Prostate gland - answer-Below the urinary bladder What does the Prostate gland encircle? - answer-First part of the urethra What percentage of semen volume does the prostate gland form? - answer-20-30% What is most of the urethra surrounded by? - answer-The Penis What does the Penis release? - answer-Urine or semen to the exterior What is the body of the Penis composed of? - answer-It is composed of cylindrical columns of erectile tissue: -2 Corpus Cavernosa which surrounds the artery -1 corpus spongiosum which surrounds the urethra What does the Corpus Spongiosum extend to form? - answer-The glans (the distal end of the penis) Scrotum - answer-A pouch lined by skin What divides the Scrotum into two chambers? - answer-Divided into 2 chambers or cavities by a scrotal septum Where do the testes lie? - answer-Each testes lies within a separate scrotal chamber Which two muscles are the Scrotum associated with? - answer--Outer Dartos -Inner Cremaster Dartos Muscle - answer-A layer of smooth muscle within the scrotum skin What does the Dartos Muscle cause? - answer-The characteristic wrinkling of the scrotal surface Cremaster Muscle - answer-A layer of skeletal muscle deep to the scrotum skin Why is the Cremaster muscle important? - answer-It is important for temperature regulation for the testes by moving the testes away from of towards the body What does sexual arousal of the Male Sexual Response entail? - answer-It initiates secretion of the bulbourethral glands which lubricates the urethra and the surface of the glans What are the three coordinated processes of the Male Sexual Response? - answer--Erection -Emission -Ejaculation Erection: Step 1 - answer-Bloodflow from the arteries into the erectile tissue increases, in which case the erectile tissue becomes engorged with blood due to parasympathetic action. Erection: Step 2 - answer-Pressure exerted on the surrounding connective tissue sheath collapses the dorsal vein and prohibits drainage of blood out of the penis What does Erection result in? - answer-The penis stiffens and assumes a more upright position Emission - answer-Peristaltic contractions of smooth muscle in the walls of the ductus deferens, seminal vesicles, and prostate gland pushes semen into the urethra What type of nerve stimulation is emission associated with? - answer-Sympathetic nerve stimulation Ejaculation - answer-Occurs as rhythmic contractions in skeletal muscles surrounding the erectile tissue at the base of the penis What occurs in Ejaculation? - answer-Semen is pushed out due to somatomotor nerve stimulation of these skeletal muscles and is accompanied by orgasm Function of the Cardiovascular System - answer-To transport materials to and from all the cells in the body What materials do the Cardiovascular system transport? - answer-1. Oxygen and CO2 2. Nutrients 3. Hormones 4. Immune system components 5. Waste products Components of the Cardiovascular System - answer-1. A pump (the heart) 2. A conducting system (the blood vessels) 3. A fluid medium (the blood) Location of the Heart - answer-Located deep to the sternum and slightly to the left Location of the "Great Blood Vessels" - answer-The base of the heart The heart is surrounded by what? - answer-A pericardial sac that prevents friction between the heart and surrounding structures of the heart (ribs, lungs, etc.) as the heart moves with each beat Function of Right Atrium - answer-Collects low oxygen blood from the upper and lower body How does the blood get into the right atrium? - answer-Via the superior and inferior vena cava Function of the Right Ventricle - answer-Pumps low oxygen blood to the lungs How does the right ventricle pump blood into the lungs? - answer-Via the right and left pulmonary arteries Function of the Left Atrium - answer-Collects high oxygen blood from the lungs How does the left atrium collect blood? - answer-Via the right and left pulmonary veins Function of the Left Ventricle - answer-Pumps high oxygen blood to the body via the aorta The Left Ventricle vs. Right Ventricle - answer-The Left Ventricle is larger, and its muscle is thicker and more powerful. It pumps most of the blood to the body Function of the Systemic Circuit - answer-Carries blood between the heart and the body Function of the Pulmonary Circuit - answer-Carries blood between the heart and the lungs What does the Aorta give rise to? - answer-The left and right coronary artery What does the Left Coronary Artery branch into? - answer--Anterior Interventricular Artery -Circumflex Artery What does the Left Coronary Artery supply? - answer-The anterior and left regions of the heart What does the Right Coronary branch into? - answer--Posterior Interventricular Artery -Marginal Artery What does the Right Coronary Artery supply? - answer-The posterior and right regions of the heart How does low oxygen blood return to the right atrium? - answer-Via the Coronary Sinus Where does the Coronary Sinus receive blood from? - answer-The Great and Middle Cardiac Veins Location of the Atrioventricular Valves - answer-Between the Atria and the Ventricles Right AV valve - answer-Tricuspid Left AV valve - answer-Bicuspid When do the Atrioventricular valves open and close? - answer--Open to allow blood to flow from the atria to the ventricles -Close when the ventricles contract What happens to the free edges of the AV valves? - answer-They attach to papillary muscles via Chordae Tendineae Papillary muscles - answer-Finger-like projections of Trabeculae Carneae Pectinate Muscles - answer-Bumpy ridges of muscles contained within the internal walls of the atria When do Papillary muscles contract? - answer-When ventricles contract What happens when Papillary muscles contract? - answer-The AV valves are pulled towards the ventricles which closes them and prevents the valves from prolapsing What is prolapsing and what would it cause? - answer-Opening backwards which would cause a backflow of blood How many cusps do Semilunar valves have? - answer-Semilunar Valves have 3 cusps Location of Pulmonic Valve - answer-Between the Right ventricle and the Pulmonary trunk Location of Aortic Valve - answer-Between the Left Ventricle and the Aorta When do the Semilunar Valves open and close? - answer--Open when the ventricles contract -Close when the ventricles relax How do the Semilunar valves prevent the backflow of blood? - answer-Pressure of blood closes them to prevent backflow of blood Do the Semilunar valves have muscular support? - answer-No Fibrous Skeleton - answer-Bands of connective tissue around the heart valves What are the Fibrous Skeleton attachment sites for? - answer--Valves -Cardiac Muscle Cells What type of insulation goes on between the Ventricular Muscle Cells and the Atrial Muscle Cells? - answer-Electrical The 2 types of Cardiac Muscle Cells - answer-1. Conducting System Cells 2. Contractile Cells Conducting System Cells - answer-A system of specialized cardiac muscle cells which generate action potentials at regular intervals. They depolarize rapidly and spontaneously Contractile Cells - answer--Cells that contract to pump the blood out of the heart -They make up 99% of the cardiac muscle cells Components of the Conducting System - answer-1. Sinoatrial Node 2. Atrioventricular Node 3. Conducting cells Pacemaker Cells - answer--Cells in the Sinoatrial Node -Spontaneous What do the Pacemaker Cells initiate? - answer-Action Potentials (electrical impulses leading to muscle contraction) Are the Pacemaker cells faster or slower than the cells in the Atrioventircular node? - answer-Faster Where do the action potentials spread? - answer--Via the internodal branches -In the atrial myocardium -to the Atrioventricular Node Location of the Atrioventricular Node - answer-Located where the right atrium meets the right ventricle What happens when the atria contract? - answer--The internodal stimulate the contractile muscle fibers -blood flows from the atria into the ventricles What happens to the action potentials after the atria contract? - answer-It travels from the atrioventricular node through the fibrous skeleton via the AV bundle to the apex of the heart Where are the action potentials carried at the apex of the heart? - answer-The Purkinje fibers in contact with the ventricular myocardium What are the action potentials transferred to? - answer-Contractile muscle cells Where do contractions of the ventricles begin? - answer-At the apex of the heart What is the pathway of bloodflow? - answer-1) From the left ventricle to the aorta to be distributed to the body 2) From the right ventricle to the pulmonary trunk to be distributed to the lungs What does Autonomic Innervation influence and by what means? - answer-1. Influences the rate of contraction (heart rate) by innervating the Sinoatrial node 2. Influences the forces of contraction (heart beat) by innervating the contractile cardiac muscles What effect do sympathetic and parasympathetic stimulation have on the heartbeat? - answer--Parasympathetic stimulation reduces heart rate (is usually in charge) -Sympathetic stimulation increases heart rate How does parasympathetic stimulation affect atrial contractions? - answer-Decreases force of contraction How does sympathetic stimulation affect both atria and ventricles? - answer-Increases the force of contraction The 5 classes of blood vessels - answer-1. Arteries 2. Arterioles 3.Capillaries 4. Venules 5. Veins Arteries - answer--Carry oxygenated blood away from the heart -Have a thick wall and a small lumen to withstand high blood pressure Arterioles - answer--The smallest branches of arteries -The site of vasoconstriction Capillaries - answer--The smallest blood vessels -exchange site of nutrients and waste between the blood and the cells Venules - answer--the smallest branch of veins -collect deoxygenated blood from capillaries Veins - answer--Carry low oxygen blood back to the heart -Have a thin wall and a large lumen -Has Venous Valves to prevent backflow of blood What are the 3 layers of the blood vessel wall? - answer-1. Tunica Initima (inner layer: endothelial cells + connective tissue) 2. Tunica Media (middle layer: smooth muscle) 3. Tunica Externa (outer layer: connective tissue) Composition of the wall of the Capilllaries - answer-The wall of a capillary is only composed of an endothelial cell lining internal to a basement membrane Why does the wall of a capillary have to be thin? - answer-For diffusion of nutrients out and wastes into the capillary What innervates blood vessel smooth muscle? - answer-Only sympathetic nerves Vasoconstriction - answer--Contraction of the smooth muscle in the tunica media -decrease the diameter of the lumen, especially of arterioles What causes Vasoconstriction? - answer-Sympathetic NS stimulation Vasodilation - answer--Relaxation of the smooth muscle in the tunica media -increase the diameter of the lumen, especially arteries and arterioles What causes Vasodilation? - answer-Sympathetic NS inhibition Describe Collateral Circulation - answer--Blood circulation can reach most regions of the body via more than one route because during development, vessels of a similar diameter fuse together to form Anastomotic Connections -If one route is blocked, an alternate route will deliver blood so that the tissue doesn't die What is the force developed by the heart required to do? - answer-Push blood along the network of arteries through miles of capillaries What contains 30-35% of the blood volume? - answer-The heart, arteries and capillaries in the pulmonary and systemic circulations What is the purpose of Cardiovascular regulation? - answer-To maintain adequate blood flow through the capillaries in peripheral tissues and organs What percentage of the blood volume does the venous system contain? - answer-65-70% What can't the blood pressure in the venules and veins do and why? - answer-It can't overcome the force of gravity because it is so low How does venous blood overcome the force of gravity and return back to the heart? - answer-Contraction of the surrounding skeletal muscles squeezes the blood towards the heart, and a special structure called a venous valve prevent backflow of blood Venous Valves - answer-Projections from the vessel wall that point in the direction of blood flow Location of Venous Valves - answer-Only found in limb veins What do closed venous valves prevent? - answer-Prevents the backflow of blood towards capillaries What opens the Venous Valves? - answer-Contractions of skeletal muscles compress and open the venous valves, assisting in venous return Platelets - answer--cell fragements from megakarocytes (giant cells) -involved in blood clotting -releases important clotting chemicals Red Blood Cell Distribution - answer--most numerous cells in the blood -make up 99.9% of blood's formed elements Red Blood Cell Structure - answer--Very flexible, no organelles -contains hemoglobins which bind and carry oxygen Red Blood Cell Maturation - answer-In red bone marrow White Blood Cell Structure - answer--Do not have hemoglobin, but contain nuclei and other organelles White Blood Cell Distribution - answer--Most are in Connective Tissue Proper or in the lymphoid organs. -White Blood Cells in the blood only represent a small fraction White Blood Cell Function - answer--Defense against pathogens -Remove toxins and waste -Attack abnormal cells White Blood Cell Maturation - answer-In the red bone marrow Types of White Blood Cells contributing to Nonspecific Defense - answer-1. Neutrophils (50-70% circulating WBC's) 2. Eosinophils (2-4% of circulating WBC's) 3. Basophils (less than 1% of circulating WBC's) 4. Monocytes (2-8% of circulating WBC's) Neutrophils - answer--Most numerous of the White Blood Cells -Highly mobile, first attack bacteria Eosinophils - answer-- 2-4% of circulating White Blood cells -attack parasite by exocytosis -also associated with allergic reactions -also attracted to sites of injury where they release enzymes Basophils - answer--less than 1% of circulating White Blood Cells -contain many granules -release histamine during inflammation to dilate blood vessels -release heparin to prevent blood clotting Monocytes - answer-- 2-8% of circulating WBC's -enter peripheral tissues and become macrophages Lymphocytes - answer--associated with specific defenses (aka Immune Response) -mostly in connective tissue proper and lymphatic organs -circulating lymphocytes only represent a small fraction -Two types of cells: B and T cells Purpose of Platelets - answer-To clot blood Purpose of Red blood cells (A.k.a Erythrocytes) - answer-to transport oxygen Purpose of White Blood Cells - answer-To fight infection