Brainscape's Knowledge GenomeTM

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


See full index

Reproduction > Chapter 10 > Flashcards

Chapter 10 Flashcards

1
Q

What endocrine requirements must be met so spermatozoa can be produced?

A

1) adequate secretion of GnRH from hypothalamus
2) FSH and LH secretion from the anterior lobe of the pituitary
3) secretion of gonadal steroids (testosterone and estradiol)

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

What does luteinizing hormone act on?

A

Leydig cells within the testes

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

What do leydig cells synthesize and what is this converted into?

A

progesterone into testosterone

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

What does successful testis function require?

A

pulsatile GnRH secretion, high concentrations of testosterone in the seminiferous tubule, low concentrations of testosterone in a systemic blood, and adequate LH receptors in Leydig cells

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

What do sertoli cells secrete?

A

inhibin

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

What else do the testes secrete?

A

estradiol

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

What is the female equivalent of leydig cells in the male?

A

follicular theca interna cells

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

What is the female equivalent of sertoli cells in the male?

A

follicular granulosal cells

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

What do sertoli cells convert?

A

testosterone to estradiol

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

What type of relationship does estradiol and testosterone have on the hypothalamus in the male?

A

negative feedback

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

What are the goals of spermatogenesis?

A

1) provide a continual supply of male gametes, genetic diversity, provide sperm for reproduction and an immunologically privileged site for developing germ cells.

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

What is the process of producing spermatozoa?

A

spermatogenesis

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

Where does spermatogenesis take place?

A

seminiferous tubules

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

How much more testosterone should be in testes than circulation for normal spermatogenesis?

A

100-500 x

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

Testosterone in circulation keeps what from happening?

A

negative feedback

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

What are the three phases of spermatogenesis?

A

Proliferation, meiosis, differentiation

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

What does the proliferation phase consist of?

A

mitotic divisions of spermatogonia and stem cell renewal

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

What does meiotic phase consist of?

A

2 meiotic divisions (meiosis 1 and 2) that are for genetic diversity and haploid spermatids

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

What does the differentiation phase consist of?

A

Head, mid piece, and flagellum

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

Where spermatogonia located in?

A

basal compartment of the seminiferous epithelium

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

What are the three types of spermetogina?

A

A1-A4,I, and B-spermatogonia

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

What is the last division of proliferation?

A

primary spermatocyctes

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

What is reduced in the meiotic phase?

A

chromosomes

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
Q

What are chromosomes reduced too?

A

haploid state

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
Q

What do primary spermatocytes do?

A

Immediately enter meiosis 1

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
26
Q

What takes place in meiosis 1?

A

crossing over results that are in a random assortment of different segments of each chromosome

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
27
Q

How much time does prophase of meiotic division take up of entire spermatogenic process

A

30% (long process)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
28
Q

What germ cell type has the longest lifespan?

A

primary spermatocyte

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
29
Q

What happens after the first meiotic division?

A

secondary spermatocyte rapidly undergoes the second meiotic division

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
30
Q

What does the second meiotic division result in?

A

haploid spherical spermatids

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
31
Q

What is the role of spermatozoon?

A

deliver male’s genetic material to an oocyte during fertilization and forms cells capable of fertilization

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
32
Q

What happens to these haploid spermatids?

A

their nucleus becomes highly condensed, the acrosome forms, and the cells become motile

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
33
Q

What develops on the spermatids?

A

flagellum and mitochondrial helix

34
Q

What ability is unlocked in differentiation?

A

ability to fertillize

35
Q

What are the four phases of differentiation?

A

Golgi phase, cap phase, acrosomal phase, maturation phase

36
Q

What do the four steps of differentiation do?

A

make gamete capable of moving independently with change in head shape and tail feature added

37
Q

Spermatozoa =

A

head + tail

38
Q

What does the head of the spermatozoa consist of?

A

nucleus + acrosome + post-nuclear cap

39
Q

What does the tail of the spermatozoa consist of?

A

middle piece + principal piece + terminal piece

40
Q

Where is the spermatozoa released from and where does it go?

A

sertoli into seminiferous epithelium

41
Q

Characteristic of Spermatozoa? 4 of them

A

1) Head shapes are characteristic of each species
2) DNA transcription and translation stop until fertilization
3) The anterior two thirds of the nucleus is covered in acrosome
4) the tail forms,

42
Q

What does the acrosome contain?

A

hydrolytic enzymes

43
Q

What does the acrosome undergo?

A

acrosome reaction

44
Q

What is the tail of spermatozoa?

A

self-powered flagellum

45
Q

The cycle of seminiferous epithelium?

A

yes

46
Q

What are germ cell generations?

A

cells of the same type located at one site within the seminiferous epithelium

47
Q

What should we think of the cycle of seminiferous epithelium as?

A

A university (freshman, Sophmore, Junior, Senior)

Spermatagonia -> Primary spermatocytes -> Secondary Spermatocytes -> Spermatids

48
Q

Do lifespan of cells and duration of the cycles vary among species?

A

yes

49
Q

How long is the complete process of spermatogenesis?

A

61 days

50
Q

How many cycles do these cells of the seminiferous epithelium proceed through?

A

4.5 x

51
Q

How long are these individual cycles?

A

13.5

52
Q

What is analogous to graduation?

A

spermiation (fully differentiated spermatozoon)

53
Q

Do the individual germinal elements have different lifespans though?

A

yes, 21 days for primary spermatocyte and 1.7 days for secondary spermtocyte

54
Q

Is the pace of spermatogensis affected by environment?

A

no

55
Q

What should we think of spermiation like?

A

A wave in a stadium where when you stand up you mimic spermiation (VIII) and the rest is the sitting phase (1-VII) so that the spermatogenic wave is relatively constant in its supply of spermatozoa to the epididymis for pool of ejaculation

56
Q

What is a good estimator of sperm producing ability?

A

testicular size

57
Q

How much of every ejaculate contain abnormal sperm?

A

5-15% abnormal sperm

58
Q

Where do morphological abnormalities originate?

A

testes or epididymis

59
Q

What are the two classifications of morphologically abnormal sperm?

A

head or tail abnormalitites

60
Q

T/F Female gametes are complete prior to birth?

A

True

61
Q

Spermiation process versus ovulation process?

A

uniformly v pulsatile

62
Q

What is the exception of the regular spermiation process?

A

seasonal breeders

63
Q

How long after restoration from an event that impacted spermatogensis is needed?

A

6-12 weeks

64
Q

What is the fertility of the male determined by:

A

assuming that he can copulate, sperm producing ability, viability (motility) of his spermatozoa, # of morphologically abnormal spermatozoa, and number of normal spermatozoa from ejaculation

65
Q

Two tail and head abnormalitites for spermatozoa?

A

Coiled and folded tail / tapered and knobbed heads

66
Q

What is the most important physiologic technology ever devised for accelerating genetic improvement?

A

Artificial Insemination

67
Q

What is the criteria for artificial insemination?

A

collection of semen from the male, preservation and extension of sperm, and insemination of the female

68
Q

What information is needed after collection of sperm?

A

ejaculate volume, concentration of spermatozoa, and percentage of motile sperm

69
Q

Ejaculation volume * Spermatozoa concentration =

A

total sperm in ejaculation

70
Q

What does the total number of sperm lets us know?

A

how many insemination doses are available (good is over 60% and bad is below 50%)

71
Q

total number of sperm / desired number of sperm in each does =

A

number of doses

72
Q

What is the main thing that AI provides?

A

accelerated genetic improvement to use only the best male genetics that removes need for males on farms and decreases inbreeding

73
Q

What happens after it is determined that the ejaculate is of sufficient quantity?

A

it must be diluted in an extender solution

74
Q

Is ejaculated semen sterile?

A

no

75
Q

A good seminal extender must have?

A

be isotinic, good buffers, cryoprotectants, appropaite nutrients, viability. low in cost and prevention against microbial growth

76
Q

What is the sex of the conceptus determined by?

A

sperm due to each spermatozoa containing either an X or Y chromosome

77
Q

Why is there a desire to seperate the X and Y bearing sperm?

A

one sex is significantly more valuable (dairy -> female -> lactation)

78
Q

How much more bearing is the X sperm than the Y bearing sperm?

A

2.8 - 4.2% more DNA

79
Q

Manipulation of the sex ratio under controlled conditions does what?

A

Impacts the efficiency of food animal production

80
Q

How are X and Y seperated?

A

using a DNA stain or dye called flourochrome where X absorbs more dye and thus becomes more intense light when excited by a laser in a flow cytometer

81
Q

What are ejaculated in doublets?

A

American opossum

82
Q

What does production of normal numbers of fertile spermatozoa (normal spermatogenesis) require?

A

endocrine regulation of testis, mitotic divisions of spermatogonia and meiotic divisions resulting in haploid spermatids and morphological transformation of spermatids to spermatozoa

Reproduction (11 decks)

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