Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

Endocrinology > testicular function > Flashcards

testicular function Flashcards

1
Q

up until which week are PGCs indifferent?

A
  • week 6/7
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

what occurs during male puberty?

A
  • complex process involving secondary sexual characteristic development and accelerated growth
  • initiation of gametogenesis
  • all caused by pulsatile release of GnRH from HT
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

why are the scrotum positioned outside the body?

A
  • provides a cooler environment to aid spermatogenesis
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

what 2 products are produced by the testis?

A
  • spermatozoa

- hormones

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

what are the 2 compartments within the testicles?

A
  • within seminiferous tubules (90%)–> Sertoli cells
  • nurture developing germ cells during spermatogenesis and spermiogenesis
  • between tubules (10%)–> leydig cells –> androgen producing cells (T)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

what are the 2 functions of the blood-testis barrier ?

A

Separates developing germ cells from immune system preventing immune response (anti-sperm antibodies and autoimmune orchitis – subfertility)
Controlled chemical microenvironment for spermatogenesis (selective transport of ions and small molecules)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

what are the key phases of spermatogenesis?

A
  • starts at puberty
  • takes 74 days

1) proliferation
2) division meiosis 1/2
3) differentiation –> spermiogenesis

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

what occurs during mitosis 1?

A
  • happens with pro-spermatogonia
  • occurs within the basal compartment of seminiferous tubule
  • starts at puberty
  • -> form As spermatogonia
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

what are As spermatogonia ?

A
  • reservoir of self renewal stem cells that maintain the germ line
  • they remain within the outer edge of the seminiferous tubule as unD spermatogonia
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

what do As spermatogonia form?

A
  • they form A type spermatogonia–> starts process of spermatogenesis
  • A type undergo mitosis to form B type
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

what happens to type B spermatogonia?

A
  • divide again to form primary spermatocytes of which undergo meiosis

all primary spermatocytes genetically identical to spermatogonia

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

what occurs during the resting phase ?

A
  • chromosomes within primary spermatocytes duplicate ready for 1st meiotic division
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

what happens during meiosis 1 and meiosis 2?

A

1–> primary spermatocyte divides–> secondary spermatocyte

2–> secondary spermatocyte divides –> haploid round spermatid

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

what occurs during spermiogenesis?

A
  • these round spermatids elongate to form spermatozoa
  • highly specialised but very simplistic
  • here we have the formation of specialised structures such as the acrosome, centriole, flagellum, mitochondria and the nucleus
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

what is the acrosome formed from?

A
  • formed by the Golgi apparatus of which migrates to the one end of the nucleus
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

how is the flagellum formed?

A
  • centrioles migrate to the opposite end of the nucleus to form axoneme
17
Q

why is the flagellum important?

A

it is for sperm movement through the female tract and the penetration through egg vestments

18
Q

where are the mitochondria found?

A
  • helically arranged around first part of flagellum (midplace) providing the energy for motility
19
Q

what happens to the spermatid cytoplasm?

A
  • forms a residual body (droplet)
  • phagocytksed by Sertoli cells with loss of ER organelles
  • mature sperm have very little cyt
20
Q

what occurs during spermination?

A
  • developing spermatids from a syncytium
  • persists until the final stages of spermatogenesis (last step)
  • facilitated by Sertoli cell cytoskeleton
  • formation of intercellular bridges
21
Q

what is the purpose of spermination?

A
  • allows the sharing of cytoplasmic components between spermatid and sertoli cells
  • spermatids only carry a Y chromosome, but can be supplied with essential proteins encoded on the X chromosome from Sertoli cells (such as the acrosome and axoneme)
22
Q

post testis sperm need to undergo which processes?

A
  • epididymis in male tract
  • capacitation in female tract

-both important for acquisition of motility and fertility potential

23
Q

what is the epididymis ?

A
  • is a highly segmented organs divided into 3 main anatomic regions

1) caput-> motility
2) corpus-> fertilising ability
3) cauda/vas deferens-> storage of spermatids

each segments display differential expression of genes that maintain luminal ion concentration

are essential for regulation of steps and sperm maturation

24
Q

how are sperm pushed through the 3 regions of the epididymis ?

A

via peristalsis contraction of smooth muscle of the epididymal duct

25
Q

what changes occur during migration through the epididymis ?

A

Sperm interact with epididymal epithelial cells – movement of cytoplasmic droplet Retention of cytoplasmic droplet associate with reduce fertility
 Change sperm proteome – protein, lipid and sugar content Incorporated into the sperm cells
 Change in sperm surface
Removal and/or modification of external proteins, sugars and lipid sperm membrane
 Intracellular signalling pathways activation during transit
Addition or removal of protein phosphate groups - phosphorylation

26
Q

sperm division is ?

A

even

Endocrinology (17 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions