Biol 224 Exam 4

Front 1

Which portions of the nephron are in the renal cortex?

Back 1

The renal corpuscle, PCT, DCT, and proximal portions of the loop of Henle and collecting duct

Front 2

Why don't plasma proteins pass into the capsular space under normal circumstances?

Back 2

pores of the glomerular capillaries won't allow substances the size of proteins pass into the capsular space, the filtration slits will only allow the smallest plasma proteins to pass

Front 3

Damage to which part of the nephron would interfere with the control of blood pressure?

Back 3

the juxtaglomerular apparatus (part of the distal convoluted tubule next to the afferent arteriole)

Front 4

What nephron structures are involved in filtration?

Back 4

glomerulare capillaries, lamina densa, filtration slits of the podocytes

Front 5

What occurs when the plasma concentration of a substance exceeds its transport maximum?

Back 5

the excess is not reabsorbed, it is excreted in urine

Front 6

How would a decrease in blood pressure affect the GFR?

Back 6

it would reduce the blood hydrostatic pressure within the glomerulus and decrease the GFR

Front 7

Obstruction of a ureter by a kidney stone would interfere with the flow of urine between which two points?

Back 7

between the renal pelvis and the urinary bladder

Front 8

The ability to control the micturition reflex depends on your ability to control which muscle?

Back 8

external urinary sphincter, a ring of skeletal muscle formed by the urogenital diaphragm, it acts as a valve

Front 9

The basic functional unit of the kidney is the

Back 9

nephron

Front 10

The process of urine formation involves all of the following except

Back 10

secretion of excess lipoprotein and glucose molecules

Front 11

What is the primary function of the urinary system?

Back 11

performs vital excretory functions, eliminates organic waste products, also regulates volume and solute concentration of body fluids

Front 12

What structures are components of the urinary system?

Back 12

kidneys, ureters, urinary bladder, urethra

Front 13

Name and define the 3 distinct processes involved in the production of urine.

Back 13

filtration-water and solutes pass from glomerular capillaries into capsular space
reabsorption-water and nutrients pass back into bloodstream from filtrate in tubules
secretion- wastes and ions are secreted into filtrate in tubules from blood stream

Front 14

Which parts of the urinary system are responsible for the transport, storage, and elimination of urine?

Back 14

ureters-transport
urinary bladder-storage
urethra-elimination

Front 15

When the renal threshold for a substance exceeds its tubular maximum

Back 15

the amount of substance that exceeds the tubular maximum will be found in the urine

Front 16

How are proteins excluded from filtrate? Why?

Back 16

they are too big to pass through the filtration slits of the podocytes, maintaining proteins in the plasma will keep osmotic pressure up and pull water back into the bloodstream

Front 17

Describe the micturition reflex.

Back 17

urinary bladder contains 200mL, stretch receptors stimulate parasympathetic motor neruons, action potentials reach bladder wall muscles, travel over pelvic nerves and cause bladder contractions

Front 18

Trace the path of filtrate from corpuscle to renal pelvis

Back 18

renal corpuscle, proximal ct, loop of Henle, distal ct, collecting duct, papillary duct, renal pelvis

Front 19

What effect would increased amounts of aldosterone have on the K+ concentration in urine?

Back 19

it would increase K+ concentration in urine, Na+ concentration would decrease

Front 20

What effect would a decrease in the Na+ concentration of filtrate have on the pH of tubular fluid?

Back 20

higher pH because fewer hydrogen ions could be secreted into the tubular fluid, hydrogen is secreted in as sodium is reabsorbed out of the tubular fluid

Front 21

How would the lack of juxtamedullary nephrons affect the volume and osmotic concentration of urine?

Back 21

urine would have higher volume and lower osmotic concentration because less water would be reabsorbed into the blood stream

Front 22

Why does a decrease in the amount of Na+ in the distal convoluted tubule lead to an increase in blood pressure?

Back 22

a decrease in Na+ in the DCT stimulates renin release by the macula densa cells, renin activates angiotensin which increases blood pressure

Front 23

The glomerular filtration rate is regulated by all of the following except

Back 23

cardiac output

Front 24

The distal convoluted tubule is an important site for

Back 24

active secretion of ions
active secretion of acids and other materials
selective reabsorption of sodium ions from the tubular fluid

Front 25

Changing the diameter of the afferent and efferent arterioles to alter the GFR can be an example of ___ regulation

Back 25

hormonal, autonomic, and autoregulation (local)

Front 26

Name the segments of the nephron distal to the renal corpuscle and state the function(s) of each.

Back 26

proximal convoluted tubule-reabsorbs useful organic substrates from filtrate
loop of Henle-reabsorbs over 90 percent of the water in the filtrate
distal convoluted tubule-secretes into the filtrate waste products that were missed by filtration

Front 27

What is the function of the juxtaglomerular apparatus?

Back 27

secretes the enzyme renin and the hormone erythropoietin

Front 28

What are the primary effects of angiotensin II on kidney function and regulation?

Back 28

-vasoconstriction of periphs, causing increased pressure in renal arteries
-consriction of efferent arteriole, elevating pressure and filtration rate
-stimulates reabsorption of Na and water in PCT
-causes release of ADH, which stimulates water reabsorption in DCT, thirst sensation
-casues release of aldosterone, stimulates Na reabsorption in DCT
-causes epinephrine release, elevates renal blood pressure

Front 29

Sympathetic activation of the nerve fibers in the nephron causes

Back 29

-regulation of glomerular blood flow and pressure
-stimulation of renin release from the juxtaglomerular apparatus
-the direct stimulation of water and Na reabsorption

Front 30

Sodium reabsorption in the DCT and cortical portion of the collecting system is accelerated by the secretion of

Back 30

aldosterone

Front 31

When ADH levels rise

Back 31

the amount of water reabsorbed increases

Front 32

The control of blood pH by the kidneys during acidosis involves

Back 32

the secretion of hydrogen ions and reabsorption of bicarbonate ions from the tubular fluid

Front 33

What interacting controls stabilize the glomerular filtration rate (GFR)?

Back 33

autoregulation at the local level
hormonal regulation from the kidneys
autonomic regulation (sympathetic ANS)

Front 34

What primary changes occur in the composition and concentration of filtrate as a result of activity in the proximal convoluted tubule?

Back 34

-facilitated diffusion and cotransport: 99 percent of glucose, amino acids, and other nutrients are reabsorbed
-active ion reabsorption: reduction of solute concentration
-passive diffusion: more reduced solute concentration and water reabsorption

Front 35

In a normal kidney, which of the following conditions would cause an increase in the GFR?

Back 35

a decrease in the concentration of plasma proteins in the blood

Front 36

In response to excess water in the body

Back 36

the permeability of the distal convoluted tubules and collecting ducts to water is decreased

Front 37

Why might a diuretic help to reduce arm and leg edema?

Back 37

increasing urine volume would decrease the total blood volume of the body, which would decrease blood pressure, which could decrease edema

Front 38

Why would renal arteriosclerosis cause hypertension?

Back 38

causes decreased blood flow and renal ischemia, triggers the juxtaglomerular apparatus to produce more renin, leads to angiotensin II and aldosterone, angiotensin causes vasoconstriction and increases blood pressure, aldosterone increases sodium and water reabsorption and also increases blood pressure

Front 39

If mannitol is a sugar that is filtered but not reabsorbed by the kidneys, what would drinking a solution of mannitol do to the volume of urine produced?

Back 39

it would increase the osmolarity of filtrate, which would decrease water reabsorption and increase urine volume

Front 40

On a warm day, would the cremaster muscle be contracted or relaxed? Why?

Back 40

it would be relaxed so the sac could descend away from the warmth of the body and cool the testes

Front 41

What will happen if the arteries within the penis dilate?

Back 41

allows blood flow to increase and the vascular chambers become engorged with blood, causes an erection

Front 42

What effect would low levels of FSH have on sperm production?

Back 42

low levels of testosterone which would equal lower rate of sperm production and low sperm count

Front 43

Developing spermatozoa are nourished by the

Back 43

sustentacular cells

Front 44

The ovaries are responsible for

Back 44

production of female gametes
secretion of female sex hormones
secretion of inhibin

Front 45

In females, meiosis is not completed until

Back 45

fertilization occurs

Front 46

Trace the duct system that the sperm traverses from production to exterior of body.

Back 46

seminiferous tubules, rete testis, efferent ducts, epididymis, ductus deferens, ejaculatory duct, urethra

Front 47

Which accessory organs and glands contribute to the composition of sperm? What are the functions of each?

Back 47

seminal vesicles
prostate gland
bulbourethral glands
-activate spermatozoa, nutrients for motility, propelling sperm, buffers to counter acidity

Front 48

What are the primary cell populations in the testes that are responsible for functions related to reproductive activity? What are the functions of these cells?

Back 48

-interstitial cells (Leydigs) produce male sex hormones (androgens-testosterone)
-sustentacular cells maintain blood-testis barrier, support spermatogenesis and spermiogenesis, secrete inhibin, andgrogen-binding protein, and mullerian-inhibitting factor

Front 49

Identify the three regions of the male urethra.

Back 49

prostatic urethra
membranous urethra
spongy urethra

Front 50

List the functions of testosterone in males.

Back 50

-stimulate spermatogenesis, promote maturation of spermatozoa
-maintain male accessory repro. organs
-determine male secondary sex characteristics
-stimulate metabolic operations (protein synthesis and muscle growth)
-influence brain development (sexual behaviors and sex drive)

Front 51

What are the main differences in gamete production between males and females?

Back 51

-males produce gametes their entire life, females only from menarche to menopause
-males produce many at a time, females 1 or 2 a month
-males release mature gametes that have complete meiosis, females release secondary oocytes held in meiosis II

Front 52

Describe the erectile tissues of the penis. How does erection occur?

Back 52

corpora cavernosa- tissue surrounds artery
corpus spongiosum- elastic fibers
parasympathetic neurons cause nitric oxide release, causes smooth muscles to relax in arterial walls, more blood flow, vascular channels in tissues become engorged

Front 53

As the result of infections such as gonorrhea, scar tissue can block the lumen of each uterine tube. How would this blockage affect a woman's ability to conceive?

Back 53

the sperm could not travel up and fertilize the egg, or once fertilized the egg might not be able to travel to the uterus for implantation

Front 54

What is the advantage of the acidic pH of the vagina?

Back 54

prevents bacterial, fungal, and parasitic infections in this area

Front 55

Which layer of the uterus is sloughed off during menstruation?

Back 55

the functional layer of the endometrium

Front 56

What changes would you expect to observe in the ovarian cycle if the LH surge did not occur?

Back 56

ovulation and corpus luteum formation wouldn't occur

Front 57

What effect would a blockage of progesterone receptors in the uterus have on the endometrium?

Back 57

progesterone causes functional maturation and secretion of the endometrium, so the development would be inhibited and the uterus would not be prepared for pregnancy

Front 58

What event in the uterine cycle occurs when the levels of estrogens and progesterone decline?

Back 58

the beginning of menstruation, the end of the uterine cycle

Front 59

An inability to contract the ischiocavernosus and bulbospongiosus muscles would interfere with which parts of the male sex act?

Back 59

ejaculation and orgasm

Front 60

What changes occur in females during sexual arousal as the result of increased parasympathetic stimulation?

Back 60

-erectile tissue of clitoris fill with blood
-secretion of cervical and vaginal glands increases
-blood flow to vaginal walls increases
-blood vessels in nipples engorge

Front 61

Why does the level of FSH rise and remain high during menopause?

Back 61

circulating estrogen levels drop, since estrogen has an inhibitory effect on FSH, the FSH levels get higher in absence of estrogen

Front 62

A sudden surge in LH secretion causes the

Back 62

rupture of the follicular wall and ovulation

Front 63

The principal hormone of the postovulatory phase is

Back 63

progesterone

Front 64

List and summarize the important steps in the ovarian cycle.

Back 64

1-formation of primary follicles
2-formation of secondary follicles
3-formation of a tertiary follicle
4-ovulation
5-formation and degeneration of the corpus luteum

Front 65

Describe the histological composition of the uterine wall.

Back 65

myometrium-outer muscular layer
endometrium-inner glandular layer
perimetrium-incomplete serosal layer

Front 66

Waht is the role of the clitoris in the female reproductive system?

Back 66

structural external genitalia, like a penis, contains erectile tissue, provides pleasurable sensations during arousal

Front 67

All of the following are true of pelvic inflammatory disease except that it

Back 67

can lead to a ruptured urinary bladder

Front 68

In the follicular phase of the ovarian cycle, the ovary is

Back 68

maturing a follicle

Front 69

Using an average cycle of 28 days, describe each of the three phases of the uterine cycle.

Back 69

1-menses-degeneration and loss of functional zone, 1-7 days, 35-50mL blood lost
2-proliferative phase-growth and vascularization to restore functional zone, end of menses to beginning of ovulation, around day 14
3-secretory phase-glands enlarge, more secretion, arteries enlarge in functional zone, stmulated by progestins and estrogens from corpus luteum, begins at ovulation and lasts as long as corpus luteum is intact

Front 70

Describe the hormonal events associated with the ovarian cycle.

Back 70

-follicular development, estrogen and inhibin levels rise, inhibit GnRH and FSH release
-LH gradually rises with rising estrogen
-around day 14, estrogen levels peak and LH surge causes ovulation by rupturing follicle wall
-LH stimulates corpus luteum formation, which secretes some estrogen and a lot of progesterone
-12 days after ovulation, declining progesterone and estrogen levels cause GnRH production to increase, leads to more FSH and LH, cycle starts over

Front 71

Describe the hormonal events associated with the uterine cycle.

Back 71

-corpus luteum degenerates, progesterone and estrogen levels drop, menses breakdown
-rising FSH, LH, and estrogen cause repair of functional zone
-during postovulatory phase, estrogen and progesterone cause enlargement of endometrial glands and more secretion

Front 72

Summarize the steps that occur in sexual arousal and orgasm. Do these processes differ in males and females?

Back 72

sensory nerve stimulation causes parasympathetic outflow over pelvic nerve, causes erection
orgasm from muscle contraction

Front 73

How does the aging process affect the reproductive systems of men and women?

Back 73

women-45-55 menopause, ovulation and menstruation stop, rise of GnRH, FSH, and LH, drop in estrogen and progesterone
men-50-60 male climacteric, testosterone declines, FSH and LH rise, reduction in sexual activity

Front 74

Why would peritonitis (inflammation of peritoneum) occur more commonly in females than males?

Back 74

infectious organisms can exit urethral orifice into vagina, then into uterus, uterine tubes, and finally into peritoneal cavity

Front 75

Why would a symptom of endometriosis (endometrial cells go out into peritoneal cavity) be periodic pain?

Back 75

receptors for estrogen and progesterone as if they were in the uterus, develop in size with rising hormones, can push on other tissues during peaks in hormone levels

Front 76

Contraceptive pills contain estradiol or estradiol and progesterone that prevent follicle maturation and ovulation. How?

Back 76

inhibits GnRH and FSH, LH, follicles don't develop and release, no LH surge for ovulation, mature follicles will degenerate

Front 77

What is the developmental fate of the inner cell mass of the blastocyst?

Back 77

it becomes the embryo

Front 78

Sue's pregnancy tests indicates the presence of elevated levels of human chorionic gonadotropin hCG. Is she pregnant?

Back 78

yes, after fertilization developing trophoblasts and the placenta produce and release hCG

Front 79

What are two important funcitons of the placent?

Back 79

nutrient and gas exchange, waste removal, hormone secretion

Front 80

Why does a mother's blood volume increase during pregnancy?

Back 80

Blood flow through the placenta reduces the volume of blood in the mother's systemic circuit, this stimulates an increase in maternal blood volume to compensate

Front 81

What effect would a decrease in progesterone have on the uterus during late pregnancy?

Back 81

progesterone reduces contractions, decrease could lead to contractions and labor

Front 82

The chorionic villi

Back 82

increase the surface area available for exchange between the placenta and the maternal blood

Front 83

The hormone that is the basis for a pregnancy test is

Back 83

human chorionic gonadotropin hCG

Front 84

The stage of development that follows cleavage is the

Back 84

morula

Front 85

What begins as a zygote arrives in the uterine cavity as a

Back 85

blastocyst

Front 86

The surface that provides for active and passive exchange between the fetal and maternal bloodstreams is the

Back 86

chorionic villi

Front 87

Describe the changes that occur in the oocyte immediately after fertilization.

Back 87

cell membranes fuse, oocyte activated and meiosis II finishes, no more sperm can enter, pronuclei of female and male fuse and zygote prepares for cleavage

Front 88

What are the four extraembryonic membranes?

Back 88

yolk sac, amnion, allantois, chorion

Front 89

How do the four extraembryonic membranes form, and what are their functions?

Back 89

-yolk sac from endoderm and mesoderm, site of blood cell formation
-amnion from ectoderm and mesoderm, encloses fluid sac
-allantois from endoderm and mesoderm, gives rise to the bladder
-chorion from mesoderm and trophoblast, circulation for blood carries nutrients

Front 90

Identify the three stages of labor, and describe the events that characterize each stage?

Back 90

1-dilation, cervix dilates, fetus moves toward opening, membrane ruptures
2-expulsion, cervix dilates completely, fetus emerges from the vagina
3-placental, uterus contracts, ejects placenta

Front 91

List the factors involved in initiating labor contractions.

Back 91

relaxin produced by the placenta softens pubic symphysis, weight of fetus deforms cervical os, this plus rising estrogen levels promote oxytocin release, stretched muscles become more excitable

Front 92

If a sperm cell lacked sufficient quantities of hyaluronidase, it would not be able to

Back 92

penetrate the corona radiata

Front 93

After implantation, how does the developing embryo obtain nutrients? What structures and processes are involved?

Back 93

through the chorionic villi and later the placenta

Front 94

In addition to its role in the nutrition of the fetus, what are the primary endocrine functions of the placenta?

Back 94

-produces human chorionic gonadotropin which maintains corpus luteum and therefore progesterone which keeps functional layer going
-placental lactogen and prolactin help prepare mammary glands
-relaxin increases flexibility of pubic symphysis, suppresses oxytocin release which delays labor contractions

Front 95

Discuss the changes that occur in maternal systems during pregnancy. Why are these changes functionally significant?

Back 95

respiratory rate increases, blood tidal volume increases, nutrient intakes increase, glomerular filtration increases

Front 96

During true labor, what physiological mechanisms ensure that uterine contractions continue until delivery has been completed?

Back 96

positive feedback mechanisms