Histology, Test 2, Quarter 2, Lecture 2

Front 1

Describe the blood supply of the kidney

Back 1

derived from large renal arteries: divide and do not anastomose

Front 2

Name the 5 segments of the arteries that feed the kidney

Back 2

-lobar arteries
-interlobar
-arcuate
-interlobular
-afferent

Front 3

Describe the lobar arteries of the kidney

Back 3

1 artery per lobe

Front 4

Describe the interlobar arteries

Back 4

division of the lobar artery, travels between the renal pyramids to the corticomedullary junction

Front 5

Describe the arcuate arteries

Back 5

travel perpendicular to the interlobar arteries along the corticomedullary junction

Front 6

Describe the interlobular arteries

Back 6

division of arcuate arteries which run perpendicular into the cortex

Front 7

Describe the afferent arterioles

Back 7

branches of the interlobular arteries which feed individual corpuscles

Front 8

Describe the blood supply of the glomerulus

Back 8

Consists of loops of capillaries which are branches of the afferent arterioles

Front 9

What is the function of the efferent arterioles?

Back 9

to drain the glomerulus to the second capillary bed

Front 10

Where does blood from the efferent arteriole go?

Back 10

depending on the type of nephron involved, it can go to the vasa recta of the peritubular capillaries

Front 11

What type of nephron is associated with the peritubular capillaries?

Back 11

cortical nephrons

Front 12

What type of nephron is associated with the vasa recta?

Back 12

juxtamedullary nephrons

Front 13

Describe peritubular capillaries

Back 13

arise from efferent arterioles of cortical nephrons and form a dense plexus which supplies tubules within the cortex

Front 14

Describe the vasa recta

Back 14

Main function is to help remove water from the medullary interstitium and maintain the hyperosmolarity, so there are several branches which forms capillary beds around the loop of henle

Front 15

Name the 2 subdivisions of the vasa recta

Back 15

ascending and descending

Front 16

Describe the venous drainage of the peritubular capillaries

Back 16

Drain either directly into the interlobular veins or into the stellate veins and THEN into the interlobular veins.

Front 17

Describe the venous drainage of the vasa recta

Back 17

drain directly into the arcuate veins

Front 18

Describe the path of the ureter

Back 18

travels from the renal pelvis to the bladder

Front 19

Characterize the epithelium of the ureter

Back 19

transitional epithelium

Front 20

Describe the permeability and distensibility of the ureter

Back 20

is not permeable to ions and water. Great ability to stretch as noted by the numerous "dome" cells

Front 21

What layer is directly below the epithelium in the ureter?

Back 21

connective tissue lamina propria

Front 22

What layers are deep to the lamina propria in the ureter?

Back 22

muscularis which consists of an inner longitudinal, middle circular, and outer longitudinal

Front 23

How is the muscularis fibers arranged?

Back 23

into bundles (NOT sheets like the intestine)

Front 24

Characterize the adventitia of the ureter

Back 24

blends in to surrounding connective tissue: adipose, vessels

Front 25

Characterize the epithelium of the urinary bladder

Back 25

transitional epithelium (in order to accomadate distensibility)

Front 26

Characterize the muscularis layer of the urinary bladder

Back 26

thicker than in the ureter, makes up the detrussor, inner longitudinal, middle circular, outer longitudinal

Front 27

Characterize the outermost layer of the bladder

Back 27

superior surface is serosa, everywhere else is adventitia

Front 28

Where is the urethra

Back 28

the fibromuscular tube that extend from the bladder to the exterior

Front 29

What layer is directly below the epithelium of the urethra

Back 29

lamina propria

Front 30

Name the 3 segments of the male urethra

Back 30

-prostatic
-membranous
-penile

Front 31

Characterize the epithelium of the prostatic urethra

Back 31

transitional epithelium

Front 32

Characterize the epithelium of the membranous urethra

Back 32

pseudostratified columnar or stratified columnar

Front 33

Characterize the epithelium of the penile urethra

Back 33

most of it is pseudostratified columnar, turns into nonkeratinized stratified squamous towards the glans

Front 34

Characterize the epithelium of the female urethra

Back 34

begins transitional, turns into pseudostratified columnar or stratified columnar, distally becomes non-keratinized stratified squamous

Front 35

Describe the lamina propria of the female urethra

Back 35

very vascular, resembles erectile tissue of the male

Front 36

Gland of Littre

Back 36

mucous glands (urethral glands) within the lamina propria/submucosa along the urethra

Front 37

Name the components of the male reproductive system

Back 37

testes, excurrent ducts, accessory sex glands, penis

Front 38

What is the function of the testes?

Back 38

to produce male gametes or spermatazoa, and androgens

Front 39

Name the components of the excurrent ducts of the male reproductive system

Back 39

efferent ductules, epididymidis, ductus deferens

Front 40

What is the function of the excurrent ducts?

Back 40

to help the sperm mature and deliver them to the urethra

Front 41

Name the accessory organs

Back 41

seminal vesicle, prostate, bulbourethral glands

Front 42

What are the functions of the accessory sex glands?

Back 42

to produce fluid for the semen and lubrication

Front 43

What is the outer dense covering of the testis called?

Back 43

the tunica albuginea

Front 44

What is the inner, looser layer of the capsule covering the testis?

Back 44

the tunica vasculosa

Front 45

Characterize the tunica vasculosa

Back 45

loose connective tissue with a vast blood supply

Front 46

What is the mediastinum testis?

Back 46

the thickened posterior portion of the tunica albuginea

Front 47

What is the function of the mediastinum testis?

Back 47

point where blood, nerves, genital excurrent ducts pass through to the testis

Front 48

Describe the composition of the lobules of the testis

Back 48

contain 1-4 highly coiled seminiferous tubules

Front 49

Describe the end of the seminiferous tubules

Back 49

straight portion which connects the seminiferous tubules to the rete testes

Front 50

What is the testicular intersitium?

Back 50

the space between the seminiferous tubules

Front 51

Name the components of the testicular interstitium

Back 51

nerves, blood vessels, Leydig cells

Front 52

What are Leydig cells?

Back 52

testosterone secreting cells fo the testis

Front 53

Characterize the organelle structure of the Leydig cell

Back 53

vast amounts of sER, numerous mitochondria and lipid droplets (characteristic of hormone producers)

Front 54

Describe the mitochondria of the leydig cell

Back 54

tubular cristae

Front 55

What are crystals of Reinke?

Back 55

protein granules in the Leydig cell that maybe be visible upon electron microscopy

Front 56

What is the main function of the Leydig cell>

Back 56

to produce the main androgen, testosterone

Front 57

How is Leydig cell secretion regulated?

Back 57

by feedback inhibition at the level of the anterior pituitary gonadotrophs which secrete luteinizing hormone which stimulates the secretion of testosterone

Front 58

Describe the seminiferous epithelium

Back 58

contains two types of cells and can be fairly irregular

Front 59

What surrounds the seminiferous epithelium in the seminiferous tubules?

Back 59

the tunica propria (NOT lamina propria)

Front 60

What is the tunica propria composed of?

Back 60

collagen fibrils, myoid cells, fibroblasts

Front 61

Name the 2 types of cells in the seminiferous epithleium

Back 61

1) sertoli cells
2) spermatogenic cells

Front 62

Which type of cells constitute the principal cell of the seminiferous tubule?

Back 62

sertoli cells

Front 63

Describe the structure of sertoli cells

Back 63

large, extending from apex to base of the epithelium. They have large surface area and interact with the spermatogenic cells. Light staining nucleus, irregular shaped

Front 64

Describe the connections that sertoli cells make

Back 64

They can make specialized tight (occluding) junctions that can assemble and disassemble according to need

Front 65

What do the junction complexes formed by the sertoli cells interact with?

Back 65

other sertoli cells or spermatogenic cells

Front 66

How do sertoli cells provide nourishment in the seminiferous tubules?

Back 66

they secrete a fructose product which is nutrition for the spermatogenic cells

Front 67

How do sertoli cells participate in germ cell movement and differentiation?

Back 67

They attach to the germ cells and help them move from "zone" to zone as they mature

Front 68

How do sertoli cells confer structural support upon the seminiferous tubule?

Back 68

tough cytoskeleton which allows them to maintain a certain shape. They can also transport vesicles and organelles. They form junctions (such as the blood-testis barrier)

Front 69

Name the 2 compartments that the sertoli cells form when they form tight junctions with each other

Back 69

they form the adluminal compartment and the basal compartment

Front 70

What is the function of the blood-testis border?

Back 70

maintains a unique environment within the lumen of the seminiferous tubule. Blood and lymph quality is very different from the interluminal characteristics

Front 71

Describe the immune system within the lumen of the seminiferous tubule

Back 71

suppressed

Front 72

Histologically speaking, explain why after several year vasectomies cannot be reversed

Back 72

because the body develops antibodies and when the sperm leaks out the body attacks it (it was previously protected due to the blood-testis barrier)

Front 73

Name 2 substances that the sertoli cells secrete

Back 73

androgen-binding protein and inhibin

Front 74

What is the function androgen-binding protein

Back 74

exactly what it sounds like, it binds testosterone in order to maintain high levels of the hormone to allow the sperm to grow and mature

Front 75

What controls androgen-binding protein secretion from the sertoli cell?

Back 75

FSH from the anterior pituitary

Front 76

Describe the feedback action of the sertoli cell

Back 76

secrete inhibin that inhibits the release of FSH which in turn will inhibit the secretion of ABP

Front 77

What do sertoli cells phagocytose?

Back 77

residual bodies and degenerated sperm in the seminiferous tubule

Front 78

What controls activity of the Sertoli cells?

Back 78

testosterone from the Leydig cells and FSH from the pituitary gland

Front 79

What are spermatogenic cells?

Back 79

Cells which replicate and divide into mature sperm

Front 80

How are spermatogenic cells divided?

Back 80

into layers with the most immature at the basal surface and the most mature at the adluminal surface

Front 81

Name the 4 phases of the spermatogenic cells

Back 81

1) spermatogonia
2) spermatocyte
3) spermatid
4) mature sperm

Front 82

Describe the spermatogonial phase of spermatogenic cells

Back 82

located at the basal surface of the seminiferous epithelium. Clone to make more spermatogonia

Front 83

Name the 3 types of spermatogonia

Back 83

1) Type A dark
2) Type A pale
3) Type B

Front 84

Describe type A dark spermatogonia

Back 84

ovoid nucleus that has darkly staining granules. Clone into Type A dark or Type A pale for differentiation

Front 85

What are type Ap cells derived from?

Back 85

Type Ad cells

Front 86

What is unique about Type Ap cells?

Back 86

they remain connected by thin cytoplasmic processes that don't degenerate until they have reached mature sperm phase

Front 87

What is the fate of type Ap cells?

Back 87

differentiate into Type B spermatogonia

Front 88

What are type B spermatogonie derived from?

Back 88

Type Ap cells

Front 89

What is the most mature phase of spermatogonia?

Back 89

Type B

Front 90

What do mitotic divisions of Type B spermatogonia make?

Back 90

primary spermatocyte

Front 91

Characterize Type B spermatogonia

Back 91

round nucleus that arranges chromatic into dark clumps

Front 92

What are the longest living spermatogenic cells?

Back 92

primary spermatocytes

Front 93

What do primary spermatocytes develop from?

Back 93

mitotic divisions of Type B spermatogonia

Front 94

What are secondary spermocytes?

Back 94

derived from primary spermatocytes. Undergo meiosis II

Front 95

What is the product of the meiosis II division of secondary spermatocytes?

Back 95

haploid spermatid

Front 96

What is the spermatid phase?

Back 96

the phase where haploid spermatid undergo extensive remodelling to become mature sperm

Front 97

When do proacrosomal granules coalesce?

Back 97

during the Golgi phase

Front 98

What is the fate of the proacrosomal granule?

Back 98

coalesce and bind to the nuclear envelope

Front 99

Describe the development of the tail of the sperm

Back 99

develops in the Golgi phase, doublets and central pair of centrioles form

Front 100

What happens to the spermatid in the cap phase?

Back 100

the proacrosomal granules surround the nucleus and the nuclear pores disappear. Chromatin condenses

Front 101

Describe the orientation change of the spermatid. When does this occur?

Back 101

During the acrosome phase, the spermatid head becomes embedded in a Sertoli cell with the tail sticking out toward the lumen

Front 102

How does the nucleus change during the acrosome phase of the spermatid development

Back 102

Becauses flattened and elongated, migrates anteriorly

Front 103

What is the manchette and when does it form?

Back 103

a cylindrical sheath formed by the cytoplasmic microtubules. It forms during the acrosome phase

Front 104

What is the function of the manchette?

Back 104

to aid in elongation of the spermatid

Front 105

Where do the centrioles form in the spermatid?

Back 105

In the neck region to connect the nucleus and the tail.

Front 106

What makes up the middle piece of the tail?

Back 106

mitochondria (to make ATP to aid in the beating of the flagella)

Front 107

What phase does the manchette disappear?

Back 107

in the acrosome phase of spermatid development

Front 108

What happens to the spermatid in the maturation phase

Back 108

the cytoplasmic bridges are broken and the excess cytoplasm leaves the cell as residual bodies

Front 109

What is the function of the cytoplasmic bridges between spermatogenic cells?

Back 109

to ensure synchronous development

Front 110

What is the fate of the residual bodies that leave the spermatid during the maturation phase?

Back 110

they become phagocytosed by sertoli cells