Male repro 1

Question 1

testis function

Answer 1

• production of spermatozoa
• production of hormones for sperm development and maturation, and development and maintenance of associated glands and of secondary sex characteristics

Question 2

what is found in the seminiferous tubules

Answer 2

-adluminal/abluminal compartments

Question 3

what is found in the interstitial tissue

Answer 3

• peritubular myoid cells
• leydig cells
• connective tissue and vessels

Question 4

name the four seminiferous tubule events

Answer 4

• spermatogenesis (spermatocytogenesis
• meiosis
• spermiogenesis
• spermiation

Question 5

spermatogenesis

Answer 5

• proliferation of spermatogonia

- generation of primary spermatocytes (all mitotically)

Question 6

meiosis in the seminiferous tubule

Answer 6

-reductional (M1) and equational (M2) spermatocyte division resulting in haploid spermatids

Question 7

spermiogenesis

Answer 7

-cytodifferentiation of round spermatids to elongated forms

Question 8

spermiation

Answer 8

-release of spermatozoa from sertoli cells

Question 9

how long does the diff and development of spermatogenic cells take

Answer 9

75 days

Question 10

how many sperm produced each day

Answer 10

200-200 million

Question 11

when does production of sperm stop

Answer 11

-never

Question 12

what is the ideal temp for spermatogenesis

Answer 12

32-35C (2 to 5 below 37)

Question 13

going from the basal lamina of the seminiferous tubules upwards, what are the stages of the cells present
-what cell type is between the developing sperm cells

Answer 13

• spermatogonium
• primary spermatocyte
• secondary spermatocytes
• early spermatids
• in between these cells, laterally, are ssertoli cells

Question 14

what cell type is just below the basal lamina in the seminiferous tubules?

Answer 14

-myoid cells

Question 15

what is the morphology of spermatogonia

Answer 15

-small, round cells with oval to round nuclei

Question 16

where are spermatogoni found?

Answer 16

they are resting on the basal lamina of the seminiforous tubules

Question 17

characteristics of spermatogonia type A

Answer 17

• remain undifferentiated stem cells

- these divide by mitosis

Question 18

characteristics of spermatogonia B cels

Answer 18

-undergo meiosis to form primary spermatocytes

Question 19

distinguishing A and B spermatogonia

Answer 19

-can not be done microscopically

Question 20

• where are primary spermatocytes found?
• what does their genome look like? and how many sets of chromosomes? why?
• what event takes place in this stage?

Answer 20

• found above the basal lamina, not attached
• they are diploid, 4n because they are in M1
• long prophase so they are visible in most sections, have thick chromosomes
• crossing over takes place here

Question 21

what process finishes in order to create a secondary spermatocyte?

• what is their chromosome number
• divisional characteristic

Answer 21

• M1 finishes to produce secondary spermatocytes
• haploid, 2n
• these rapidly finish M2 division

Question 22

where are early spermatids found?

• what is their morph?
• ploidy
• are they meioticcally active?
• what process do they undergo and what happens

Answer 22

• close to the lumen of the seminiferous tubule
• small round to elongated
• haploid, 1n DNA
• do not divide any further
• undergo spermiogenesis which is the differentiation into a spermatozoa

Question 23

where, specifically, does sperm differentiation and maturation take place and what is this called?

Answer 23

• the cells are embedded in sertoli cells

- called spermiogenesis

Question 24

wht are the two events that take places during spermiogenesis

Answer 24

• development of the acrosome

- formation of the tail (flagellum elongation)

Question 25

what is the acrosome

Answer 25

- golgi-derived | - contains enzymes to break through granulosa cells and zona pellucida

Question 26

what happens to the excess cytoplasm during spermiogensis

Answer 26

- these are called residual bodies | - they are discarded and sperm released into lumen (spermiation)

Question 27

are sperm motile when they are released from sertoli cells

Answer 27

-no

Question 28

what is unique about the way that sperm cells develop | -what is the technical term for this

Answer 28

- they are all unique yet groups of them share a cytoplasmic bridge - complete karyokinesis but incomplete cytokenesis

Question 29

what do the development of clonal groups yield?

Answer 29

heterogeneous seminiferous tubule wall

Question 30

morph of sertoli "nurse" cells? - what R is found on their surface? - -what does the cytoplasm surround

Answer 30

- large, euchromatic nucleus and contains a prominent round nucleolus, usually erpendicular to basal lamina - FSH - spermatogenic cells

Question 31

5 functions of sertoli cells - spermatogenic - blood - clean up - secretions - release

Answer 31

- provide physical and nutritive support for developing spermatogenic cells (control all access from blood to lumen) - form the blood-testis barrier (protection from autoimmune attack) - phagocytosis of residual bodies shed during spermatozoa maturation - secrete fluid and produce androgen binding protein, inhibin and activin to regulate FSH, endothelin to promote tubule contraction - facilitate release of sperm into tubular lumen

Question 32

sertoli sertoli cell junctions form

Answer 32

- the blood testis barrier - this is necessary since the primary spermatocytes have undrgone crossing over - this is formed using actin connections

Question 33

myoid cells are found where? - characteristics - function - receptors

Answer 33

- interstitial tissue - myofibroblast-like - function in tubular contractility and sperm transport (they are not yet mobile) - contain receptors for endothelin (made by sertoli cells) which stimulates contraction

Question 34

where are leydig cells found? - characterisstics - secrete what? - receptors

Answer 34

- found in the interstitial tissue of the seminiferous tubules - secrete cholesterol ester, have abundant SER, and tubular christae - secrete testosterone - possess LH receptors (interstitial cell stimulating hormone) and prolactin receptors

Question 35

function of testosterone

Answer 35

- essential for spermatogenesis - secondary sex characteristics - accessory gland development

Question 36

cryptorchidism

Answer 36

- one or both testis fail to descend - if bilaterla fertility is near zero - cancer rates are increased - leydig and sertoli cells unaffected so these people have normal sex characteristics