Spermatogenesis

Question 1

What is Spermatogenesis?

Answer 1

The production of sperm in the testis.

Question 2

What do the same hormones that regulate the female cycle drive?

Answer 2

Spermatogenesis.

Question 3

What are the levels of hormones that drive the female cycle and spermatogenesis?

Answer 3

Different.

Question 4

What does FSH stimulate?

Answer 4

The production of androgen binding protein (ABP) by Sertoli cells.
The formation of the blood-testis barrier.

Question 5

Where does FSH help?

Answer 5

Concentrate testosterone in the testis.

Maintain the correct structures that are necessary for coordinated spermatogenesis.

Question 6

Where does negative feedback occur in spermatogenesis?

Answer 6

At the level of the brain.

Question 7

Why does negative feedback occur at the level of brain in spermatogenesis?

Answer 7

To regulate testosterone production.

Question 8

Where does negative feedback at brain level in spermatogenesis occur?

Answer 8

Through the actions of testosterone and inhibin.

Question 9

What does testosterone do in the negative feedback at brain level in spermatogenesis?

Answer 9

Inhibits GnRH + LH release.

Question 10

What does inhibin do in the negative feedback of spermatogenesis at brain level?

Answer 10

Inhibits FSH release.

Question 11

Of what is the male reproductive system composed?

Answer 11

Testis.
Accessory organs.
Connecting ducts.

Question 12

What does the seminal vesicle produce?

Answer 12

Seminal fluid.

Question 13

What does seminal fluid add?

Answer 13

Components =like fructose, citric acid and prostaglandins.

Question 14

Why does seminal vesicle produce seminal fluid?

Answer 14

To ejaculate.

Question 15

What are some of the components of seminal fluid, like fructose?

Answer 15

Useful to the sperm.

Question 16

Why are the components of seminal fluid useful to the sperm?

Answer 16

For energy.

Question 17

What do prostaglandins influence?

Answer 17

Sperm and female tract.

Question 18

What do the secretions of the prostate include?

Answer 18

Proteolytic enzymes.
Prostatic acid phosphatase.
Fibrinolysin.

Question 19

What do prostate secretions help?

Answer 19

Liquefy semen.

Question 20

What are zinc and prostate-specific antigen?

Answer 20

Essential components.

Question 21

What is the role of PSA?

Answer 21

Liquifying the gelatinous semen.

Question 22

How does PSA liquify the gelatinous semen?

Answer 22

By breaking down a protein matrix.

Question 23

How is protein matrix, that breaks down so PSA can liquify the gelatinous semen, called?

Answer 23

Semenogelin.

Question 24

What does Semenogelin coat?

Answer 24

The sperm.

Question 25

Why does the vas deference contract?

Answer 25

To help expel the sperm.

Question 26

How does the vas deferens appear in the process of vasectomy?

Answer 26

Cut. | Tied.

Question 27

Where is the longitudinal section of a testicle?

Answer 27

In the top LHS.

Question 28

How are the seminiferous tubules shown in the longitudinal section of a testicle?

Answer 28

Tightly packed.

Question 29

What are the seminiferous tubules?

Answer 29

The site of spermatogenesis.

Question 30

Where do the sperm germ cells sit in the tubule TS?

Answer 30

Against the basement membrane.

Question 31

By what are the sperm germ cells divide in the tubule TS?

Answer 31

Mitosis.

Question 32

Why are the sperm germ cells divide by mitosis?

Answer 32

To produce one daughter cell. | Replace the divided cell and one cell that will undergo meiosis.

Question 33

What will the cell that will undergo meiosis become?

Answer 33

4 Sperm cells.

Question 34

Where does spermatogenesis occur?

Answer 34

Outward towards the lumen.

Question 35

Why does spermatogenesis occur outward towards the lumen?

Answer 35

So the sperm can be taken to the site of storage in the epididymis.

Question 36

With what is a tissue section stained?

Answer 36

A dye that binds to the DNA in the nucleus.

Question 37

Of what is the tubule packed?

Answer 37

Cells.

Question 38

What are the positions of the Leydig and Sertoli cells?

Answer 38

Important.

Question 39

Where are the Leydig cells found?

Answer 39

Around between tubules.

Question 40

Where can Leydig cells and testosterone diffuse?

Answer 40

Across the basement membrane.

Question 41

Where are the Sertoli cells found?

Answer 41

Inside.

Question 42

What do the Sertoli cells form?

Answer 42

The blood-testis barrier.

Question 43

What does the blood-testis barrier protect?

Answer 43

The developing sperm.

Question 44

Where are the blood vessels found?

Answer 44

Outside the tubule.

Question 45

Where are the cellular connections found?

Answer 45

Between adjacent Sertoli cells from the blood-testes-barrier.

Question 46

Where are the germ cells/spermatogonia?

Answer 46

Beneath BTB on the basement membrane.

Question 47

Through where must a daughter cell pass?

Answer 47

The barrier.

Question 48

How does the daughter cell pass through the barrier?

Answer 48

In a controlled, regulated manner as the barrier must loosen.

Question 49

Where do the cell moves as meiosis proceeds?

Answer 49

Towards the lumen.

Question 50

What does one cell become as meiosis proceeds?

Answer 50

4.

Question 51

How do the 4 cells produced by one cell in meiosis remain?

Answer 51

Connected.

Question 52

By which factors do the 4 cells produced by one cell in meiosis remain connected?

Answer 52

Cytoplasmic bridges.

Question 53

Until when do the spermatids remain connected in meiosis?

Answer 53

Morphological changes give the cells its characteristic appearance.

Question 54

What is the characteristic appearance of a spermatid?

Answer 54

A long tail and elongated head.

Question 55

What happens to the excess cytoplasm and cellular components?

Answer 55

They get lost.

Question 56

Where do excess cytoplasm and cellular components lost?

Answer 56

In residual bodies.

Question 57

What can Sertoli cells do?

Answer 57

Phagocytose. | Destroy damaged sperm cells.

Question 58

How many sperms are produced per heart beat?

Answer 58

1000.

Question 59

How many days does a single wave of spermatogenesis take over in a man?

Answer 59

70 days.

Question 60

When do morphological and DNA changes occur?

Answer 60

During spermatogenesis.

Question 61

From where are spermatogonia that reside near the basement membrane derived?

Answer 61

Spermatogonia stem cells (SSC).

Question 62

Where do spermatogonia near the basement membrane, derived from spermatogonia stem cells enter?

Answer 62

Spermatogenesis.

Question 63

Into what types do spermatogonia near basement membrane, derived from spermatogonia stem cells, differentiate?

Answer 63

As cells.

Question 64

By what are spermatogonia that are differentiated into type As cells followed?

Answer 64

A1-A4. | Intermediate (In) spermatogonia.

Question 65

To what do type B spermatogonia transform?

Answer 65

Preleptotene spermatocytes.

Question 66

What are the preleptotene spermatocytes?

Answer 66

The germ cells that must be transported across the blood-testis barrier (BTB).

Question 67

What does BTB divide?

Answer 67

The seminiferous epithelium.

Question 68

Into what do BTB divide the seminiferous epithelium?

Answer 68

The ad luminal and the basal compartment.

Question 69

What does ad luminal mean?

Answer 69

Towards the lumen.

Question 70

As what are Meiosis 1 and 2 and all the cellular events of post meiotic development known?

Answer 70

Spermiogenesis. | Spermiation.

Question 71

What is spermiation?

Answer 71

The process by which mature spermatids are released from Sertoli cells into the seminiferous tubule lumen prior to their passage to the epididymis.

Question 72

Where do Meiosis 1 and 2 and all the cellular events of post meiotic development take place?

Answer 72

In the ad luminal compartment.

Question 73

What happens during Meiosis 1 and 2 and all the cellular events of post meiotic development?

Answer 73

Millions of spermatozoa are formed efficiently. | Developing germ cells are being transported progressively.

Question 74

From where are developing germ cells transported?

Answer 74

The basal.

Question 75

To where are developing germ cells transported?

Answer 75

The ad luminal compartment. | The edge of the seminiferous tubule lumen.

Question 76

Where are mature spermatozoa released at?

Answer 76

Spermiation.

Question 77

Where do mature spermatozoa enter?

Answer 77

Seminiferous tubule lumen.

Question 78

Why do mature spermatozoa enter the seminiferous tubule lumen?

Answer 78

For their eventual maturation.

Question 79

Where do mature spermatozoa eventually maturate?

Answer 79

In the epididymis.

Question 80

When do DNA changes occur?

Answer 80

During meiosis of 2 chromosomes.

Question 81

At what stage does the pairing of homologous chromosomes happen?

Answer 81

The zygotene stage.

Question 82

What happens to the DNA by the pachytene stage?

Answer 82

It is duplicated.

Question 83

When does crossing over occur?

Answer 83

At the diplotene stage.

Question 84

What factors are formed when Meiosis 1 proceeds?

Answer 84

2 secondary spermatocytes.

Question 85

Through what do the 2 secondary spermatocytes transited?

Answer 85

Meiosis 2.

Question 86

What do the 2 secondary spermatocytes form when they are transited through meiosis 2?

Answer 86

4 interconnected spermatids.

Question 87

What do the 4 interconnected spermatids undergo?

Answer 87

Morphological changes.

Question 88

During what did the 4 interconnected spermatids undergo morphological changes?

Answer 88

Spermiogenesis.

Question 89

By what is spermiogenesis followed?

Answer 89

Spermiation.

Question 90

What do most sperms have?

Answer 90

A tail.

Question 91

What can the morphology of the head do?

Answer 91

Differ.

Question 92

Where does the change of the head morphology differentiation is most notable seen?

Answer 92

In mouse sperm.

Question 93

Why is the function of the hook not known?

Answer 93

Because, the sperm doesn't bind to the egg using the hook.

Question 94

How does the human sperm look?

Answer 94

A spatula with a flat oval head.

Question 95

With what does the size of the sperm heads appears to be correlated?

Answer 95

Genome size.

Question 96

What are the thickness of flagella in mammalian sperm?

Answer 96

Larger.

Question 97

What does the larger thickness of flagella in mammalian sperm reflect?

Answer 97

The more challenging swimming environment in vivo animals compared to the external fertilisers.

Question 98

By what is spermatogenesis driven?

Answer 98

The same hormones as oogenesis.

Question 99

What are the three key cell types that are necessary for spermatogenesis?

Answer 99

1. Spermatogonia sperm cells. 2. Leydig cells. 3. Sertoli cells.

Question 100

What stage event is spermatogenesis characterised?

Answer 100

A complex multi stage event.

Question 101

What does spermatogenesis involve?

Answer 101

``` Molecular Genomic Physiological Morphological --> changes. ```

Question 102

How is the sperm cell shape across species characterised?

Answer 102

Highly conserved.