A&P Lecture Exam 3

List the organs of the urinary system (4)

Kidneys, ureters, urinary bladder, and urethra

Describe the main functions of the kidneys (6)

1. Excretion (filter blood and produce filtrate)

2. Regulation of blood volume/pressure

3. Regulation of blood ion concentration

4. Regulation of pH

5. Erythropoiesis

6. Vitamin D Production

Describe the location and makeup of the renal capsule (external)

surrounds the exterior of the kidney and is made up of fibrous connective tissue

Describe the location and makeup of perirenal fat (external)

surrounds the renal capsule, held in place by the renal fascia, and is a thick layer of adipose tissue

Describe the location and makeup of the renal fascia (external)

anchors the kidneys and fat to the abdominal wall. A thin layer of connective tissue

Describe the location and makeup of the hilum (external)

medial side of each kidney where blood vessels, nerves, and ureters enter/exit

Describe the location of the renal cortex (internal)

outer layer of the kidney

Describe the location of the renal medulla (internal)

inner layer of the kidney

Describe the structure and function of the renal columns (inner)

Extentions of the renal cortex into the medulla between the renal pyramids

Describe the structure and function of the renal papillae (inner)

located at the apex of the renal pyramid

Describe the structure and function of the renal sinus (inner)

cavity at the tip of the renal column that is filled with adipose tissue, loose connective tissue, and blood vessels

Describe the structure and function of the minor calyx (inner)

funnel shapped chambers that renal papillae extend. Each kidney has 8-20 and they merge to form major calyces.

Describe the structure and function of the major calyx (inner)

larger funnels and each kidney contains 2-3. They converge to form the renal pelvis

Describe the structure and function of the renal pelvis (inner)

enlarged chamber that collects urine from the major calyces. Narrows into the ureter

List the pathway of urine flow from the collecting ducts to the ureter

collecting ducts - papillary ducts - renal papillae - minor calyx - major calyx - renal pelvis - ureters

Describe the structure and function of Bowman’s capsule (nephron)

enlarged end of nephron surrounding glomerulus, filtration occurs here and its the first main step to produce urine

Describe the structure and function of the glomerulus (nephron)

network of capillaries that helps create filtrate

Describe the structure and function of the renal corpuscle (nephron)

consists of the Bowman’s capusle and glomerulus

Describe the structure and function of the proximal convoluted tubule (nephron)

reabsorbs 65% of filtrate water and NaCl. Water flows passively while filtrate volume is reduced. Gets fluid from the Bowman’s capsule.

Describe the structure and function of descending loop of Henle (nephron)

Filtrate volume reduced 15% and water exists passively. Moves out and enters the vasa recta

Describe the structure and function of ascending loop of Henle (nephron)

reabsorbs 25% of filtrate NaCl. Not permeable to water Na, Cl, K transported out of filtrate

Describe the structure and function of distal convoluted tubule (nephron)

water movement out is regulated by ADH. If ADH is absent it water not reabsorbed and dilute urine is produced (increased urine). Reabsorb 19% of filtrate water

Describe the structure and function of collecting duct (nephron)

reabsorb 9-10% of filtrate water. extends from the cortex to the medulla

Describe the structure and function of peritubular capillaries (nephron)

surround the proximal and distal convoluted tubules. Drain into the interlobular veins

Describe the structure and function of vasa recta (nephron)

specialized parts of peritubular capillaries extend deep into the medulla and surround the loop of Henle. Removes excess water and solutes in the medulla without destroying the interstitial fluid

Describe a cortical nephron

85% of total nephrons that are located in the cortex. Does not go as deep into the medulla

describe a juxtamedullary nephron

have extensive thin segments that are involved in the production of concentrated urine. Have loops of Henle deep into the urine.

Explain the blood supply of the nephron (afferent arteriole through vasa recta)

Afferent Arteriole→Glomerulus→Efferent Arteriole →Peritubular Capillaries→ Vasa Recta

Describe the effects of ADH on urine volume

Indirect relationship. Increased ADH decreases urine volume, decreased ADH increases urine volume

Describe the effects of ADH on urine concentration

Direct relationship. Increased ADH increases urine concentration, decreased ADH decreases urine concentration

Describe the effects of ADH on blood volume/pressure

Direct relationship. Increased ADH increases blood volume/pressure, decreased ADH decreases blood volume/pressure

Describe the effects of ADH on blood osmolality

Indirect relationship. Increased ADH decreases blood osmolality, decreased ADH increases blood osmolality

Describe the effects of ADH on water absorption

Direct relationship. Increased ADH means increased water reabsorption and decreased ADH means decreased water reabsorption

Describe the effect of ADH on collecting ducts and distal convoluted tubules

Increases water permeability by stimulating the insertion of aquaporins. With ADH there is a small volume of concentrated urine and with no ADH there is a large volume of dilute urine

Describe the strucutre and function of the ureters

transport urine to the urinary bladder through peristalsis

Describe the strucutre and function of the urinary trigone

has the 2 ureteric orifices and urethral orifice. Funnel urine and senses when the bladder is full

Describe the strucutre and function of the urinary detrusor

layers of smooth muscle located in the wall of the bladder. Contraction propels urine

Describe the strucutre and function of the urinary transitional epithelium

lines the inner surface of the bladder and permits changes in size of the bladder due to changes in urine volume

Explain the pathway and cause of urine flow from the kidney to the urinary bladder

renal pelvis → ureter → urinary bladder

Discuss the micturition reflex

empyting of the urinary bladder by stretch of the bladder wall. Bladder contracts and inhibits the external urethral sphincter. Voluntary relaxation of this permits urination and contraction prevents it.

Describe the intracellular fluid compartment including the primary anions and cations

all fluids inside cells of a body, is about 40-50% of total body weight. Includes K+ and PO3-

Describe the extracellular fluid compartment including the primary anions and cations

all fluid outside cells and is about 25-30% of body weight. Includes interstitial fluid, plasma, lymph, CSF, synovial fluid, serous fluid. Na+ and Cl-

Describe the sources of water in the body

through ingestion and cellular metabolism

Describe how water is regulated in the body (4 things)

osmolality, osmosis, baroreceptors, and learned behavior

Describe how water is lost in the body

urine, evaporation (peristalsis and respiratory passages), and feces

Descuss how body fluid osmolality is achieved and held in homeostatic balance

adding or removing water changes the osmolality. Increased osmolality includes triggered thrist and ADH secretion while decreased osmolality inhibits thirst and inhibits ADH secretion.

List the 4 mechanisms to regulate blood volume

neural, renin-angiotensisn-aldosterone, atrial natriuretic hormone (ANH), and antidiuretic hormone (ADH)

Describe how intracellular fluid composition is maintained (4 things)

1. Selectively permeable membrane

2. Active transport with pumps

3. osmotic balance/aquaporins

4. secondary active transport

Describe how sodium ion concentration is regulated (sensible vs insensible perspiration)

Kidneys are the main route of excretion and small quantities are lost in sweat. Sensible perspiration is water evaporation from skin while insensible is secreted by the sweat glands that contains solutes

Describe at least two symptoms of hypernatremia

thirst, fever, dry mucous membranes, and restlessness

Describe at least 2 symptoms of hyponatremia

confusion, apprehension, seizures, coma

explain how potassium is regulated homeostasis

Maintained in narrow range that affects resting membrane potentials. Aldosterone increases the amount secreted

Describe at least 2 symptoms of hyperkalemia

muscle weakness, intestinal cramping, diarrhea, rapid cardiac depolarization

Describe at least 2 symptoms of hypokalemia

bradycardia, decreased smooth muscle tone, atrioventricular block

Decribe the calcium ion homeostasis (PTH and calcitonin)

PTH increases extracellular Ca2+ levels and decreases extracellular phosphate levels. Calcitonin decreases extracellular Ca2+ levels

List at least 2 symptoms of hypocalcemia

confusion, muscle spasms, convulstions, hyperreflexia

List at least 2 symptoms of hypercalcemia

fatigue, weakness, anorexia, nausea, constipation

Describe buffers in acid-base balance

responded almost instantaneously to changes in pH and they are not as precise

Describe respiratory center as a mechanism of acid-base balance

takes minutes to respond to pH changes and it is not as precise

Describe renal regulation as a mechanism of acid-base balance

may take hour to days to respond to pH changes but it is very precise. The kidneys have the greatest ability to regulate pH precisely

List the 3 mechanisms of acid-base balance

1. Buffers

2. Respiratory center

3. Renal regulation

Describe how hyperventilation helps regulate pH levels

decreases blood CO2 levels, respiratory rate increases, and pH increases

Describe how hypoventilation helps regulate pH levels

increases blood CO2 levels and decreases respiratory rate. pH therefore decreases

Contract acidosis and alkalosis (pH level and respiratory vs. metabolic causes)

acidosis - body pH below 7.35. Caused by hypoventilation and metabolically can occur from diarrhea, vommiting,untreted diabetes, anaerobic respiration, etc.

alkalosis- pH above 7.45. Caused by hyperventilation and metabolically can occur from severe vommiting, too much aldosterone, ingestion of substances like bicarbonate of soda

What are the 4 main functions of the reproductive system in both males and females?

1. Production of gametes (sperm and oocytes)

2. Fertilization

3. Development and nourishment of new individual

4. Production of reproductive hormones

What are the primary sex organs in males and females? What is their function:?

called gonads or testes and ovaries and they produce gametes and sex hormones

What are the primary sex hormones in males and females?

males: testosterone

females: estrogen and progesterone

What are the functions of the male reproductive system? (3)

1. Production of sperm cells

2. Sustenance transfer of sperm cells to the female

3. Production of male sex hormones

What are the functions of the female reproductive system (4)

1. Production of female sex cells (ova)

2. Reception of sperm cells from the male

3. Nurturing the development of and providing nourishment for the developing fetus

4. Production of female sex hormones

two chambered sac containing the testes

scrotum

What are the testes separated by?

raphe

Describe the two muscles inside of the scrotum

Dartos: smooth muscle that wrinkles scrotal skin

Cremaster: bands of skeletal muscle that elevate the testes and keep them at 3 ^°C lower than the core body temperature

Describe the spermatic cord and what it includes

Includes the ductus deferens, blood and lymphatic vessles, nerves. On both sides

The covering of it includes external spermatic fascia, cremaster muscle, and internal spermatic fascia

Passes through the inguinal canal into the abdominal cavity

Describe the descent of the testes

pass from the inguinal cavity to the scrotum and is guided by the gubernaculum. Testes start to show around 8 weeks and continue to descend until 9 months with structures inside growing as well. As an adult, the gubernaculum becomes the scrotal ligament

Describe cryptorchidism

Failure of one or both the testes to descend into scrotum. This prevents normal sperm development

Describe the seminiferous tubules

they produce sperm cells and converge to form the tubulus rectus

Describe sustentacular cells

nourishing sperm cells and produce hormones. Contain tight junctions that form a blood-testis barrier

What is the function of the interstital cells?

surround the seminiferous tubules and they produce testosterone

Describe spermatogenesis

Sperm cells are produced in the seminiferous tubules. Spermatogenic cells of the seminiferous tubules (puberty) give rise to sperm in a series of events: mitosis, meiosis, and spermatogenesis

Describe mitosis of spermatogenesis

Primary cells undergo this. spermatagonia form two haploid secondary spermatocytes

Describe meoisis of spermatogenesis

secondary spermocytes form spermatids

Describe spermiogenesis of spermatogenesis

spermatids form an acrosome and flagellum to become sperm

List the male duct system in order from epididymis through the urethra

epididymis → ductus deferens → prostatic urethra →membranous urethra → spongy uretha

Describe the epididymis

coiled tube system located on the testes. SITE OF SPERM CELL MATURATION consists of a head, body, and tail. During ejaculation, the epididymis contracts

describe the ductus deferens

runs from the epididymis through inguinal canal to the abdominal cavity. Transports sperm from the epididymis to the prostatic urethra

What is a vasectomy?

cutting and tying of the ductus deferens - almost 100% effective form of birth control, can be reversed.

Describe the prostatic urethra

extends from the urinary bladder through the prostate gland to the membranous urethra

Describe the membranous urethra

extends through the pelvic floor and becomes the spongy urethra

describe the spongy urethra

extends through the penis to the exterior of the body

Describe the basic aspects of the penis

copulatory organ designed to deliver sperm into the female reproductive system. Consists of a root and a free shaft that ends in the enlarged glans penis

What is the root of the penis?

bulb and crura and it attatches the penis to the coxal bones

Describe the corpora cavernosum spongy erectile tissue of the penis

form the dorsum and sides of the penis

Describe the corpus spongiousum spongy erectile tissue of the penis

surrounds the urethra and expands to form the glans and bulb of penis

What happens to the spongy erectile tissue during and erection?

the tissue fills with blood causing the penis to enlarge and become rigid

Describe the seminal vesicles

posterior wall of the bladder that joins to form the ejaculatory duct. Mixes seminal fluid into the ejaculatory duct

describe the prostate gland

donut shaped gland that encircles part of the urethra inferior to the bladder. Consists of glandular and muscular tissue and empties into the prostatic urethra

Describe the bulbourethral glands

pea-sized glands inferior to the prostate. Mucous glands that empty into the spongy urethra

List the 4 components of ejaculate

1. Testicular secretions

2. Seminal vesicle fluid

3. Prostate secretions

4. Bulbourethral gland mucus

Describe testicular secretions and the percent of total ejaculate volume

contain sperm cells. about 1-5% of total volume

Describe seminal vesicle fluid and the percent of total ejaculate volume

contains fructose, clotting proteins, and prostaglandins. makes up about 60% of the total volume