Brainscape's Knowledge GenomeTM

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


See full index

AN S 331 > Exam 2 > Flashcards

Exam 2 Flashcards

1
Q

The hypothalamus is inherently ____________? Why?

A

Female because testosterone androgenizes the surge center

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

The estradiol produced by the ovary binds to what in order for it to be too big to cross the blood-brain barrier, essentially allowing the surge center to develop in females?

A

Alpha feto-protein

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

An increase in average daily gain (ADG) results in a

A

Decreased age at puberty.

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

List the five environmental factors that affect puberty onset in females.

A

1) Breed
2) Exposure to male
3) Season of birth
4) Photoperiod
5) Group size and density

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

What two factors affect GnRH neuron development?

A

1) Body condition
2) Exposure to environmental and social cues

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

Females need to have a completely functional ______ in order for puberty to be maintained?

A

Surge center

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

Define the estrous cycle.

A

Events that happen between periods of sexual receptivity

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

What are the two phases of the estrous cycle? What hormone is high in each phase? What structure is present on the ovary during each phase?

A

1) Follicular Phase; Estradiol; Follicle
2) Luteal Phase; Progesterone; CL

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

What is the term used for an animal not cycling at a given time?

A

Anestrus

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

List the 5 (maybe 7) times in a female’s life that she will most likely not be cycling.

A

1) Pregnancy
2) Lactation
3) Season
4) Stress
5) Disease and illness
6) (presence of offspring)
7) (Prior to puberty)

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

List the three types of cycles we talked about in class, be able to explain how they work, and give a species example of each.

A

1) Monoestrous: once a year, dog
2) Polyestrous: normal, cow
3) Seasonally polyestrous: seasonally, horses, sheep

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

Proestrus + Estrus = ?

A

Follicular phase

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

Metestrus + Diestrus = ?

A

Luteal phase

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

What is superfecundation?

A

Multiple oocytes are fertilized by spermatozoa from different males (in one ovulation cycle)

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

In the bitch, which stage of the estrous cycle is the longest?

A

Anestrus

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

What phase of the estrous cycle is not present in the bitch?

A

Metestrus

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

Queens are induced _____ ?

A

Ovulators

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

Queens are in the follicular phase until copulation when the ____ surge is initiated.

A

LH

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

Queens only ovulate after ______?

A

Copulation

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

What are the four major events that occur in the follicular phase?

A

1) Ovulation
2) Sexual receptivity
3) Follicular growth
4) Elevated gonadotropin secretion, FSH, & LH

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

What is the level of concentration of estradiol during the follicular phase?

A

High

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

The tonic center is responsible for what type of secretion of which hormone?

A

Basal secretions of GnRH

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

The surge center is responsible for what type of secretion of which hormone?

A

Episodic surges of LH, which causes ovulation

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

If ______ is dominant, complete follicular development and ovulation cannot occur

A

Progesterone

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

What is the primary function of LH?

A

Complete follicular development & cause ovulation

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

What is the fate of most follicles and what causes this?

A

Atresia, because there is a lack of LH receptors

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

What type of cells are in the preovulatory follicles? What are their functions?

A

a. Theca externa - structural support and integrity
b. Theca interna - LH receptors
c. Granulosa - FSH receptors

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

What is luteinization?

A

Formation of the CL; transformation of follicle cells to luteal cells

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

Progesterone has what type of feedback on the GnRH neurons?

A

Negative

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

What structure forms after the functional CL regresses?

A

CA (corpus albicans)

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

What immune cells are present at luteolysis?

A

Cytokines

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

When we synchronize estrous, what are we trying to do?

A

Either kill or maintain the CL

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

What are two ways to manipulate the estrous cycle?

A

1) Progestogen - maintains the CL
2) Prostaglandin - kills the CL

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
34
Q

Where does spermatogenesis take place?

A

Seminiferous tubules

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
35
Q

What hormones do we need for spermatogenesis that are under endocrine control?

A

FSH, LH, & GnRH

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
36
Q

LH acts on ________ cells and dervive from what tissue?

A

Leydig; same tissue as theca interna cells

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
37
Q

FSH acts on _______ cells and derive from what type of tissue?

A

Sertoli; granulosa

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
38
Q

What are the three phases of spermatogenesis? Give a brief description of what is happening in each.

A

1) Proliferation phase - mitotic divisions
2) Meiotic phase - meiotic division
3) Differentiation phase - no cell division

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
39
Q

What are the four things we measure when looking at male fertility?

A

1) Producing ability
2) Viability
3) Morphology
4) # of normal spermatozoa

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
40
Q

What are the two methods to preserve sperm?

A

1) Extender
2) Freeze

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
41
Q

Which hormone is a glycoprotein?

A

FSH

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
42
Q

Type of receptors that bind protein hormones

A

Plasma membrane

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
43
Q

Sustained hormone secretion during pregnancy

A

P4

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
44
Q

Major limiting factor for the onset of puberty

A

Secretion of GnRH

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
45
Q

Which hormone negatively affects the development of GnRH surge center?

A

Testosterone

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
46
Q

Which of the estrous phases is the longest?

A

Diestrus

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
47
Q

Which hormone acts as a positive feedback messenger?

A

Estradiol (E2)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
48
Q

List 3 species that don’t experience lactational anestrus

A

1) Cats
2) Llama
3) Alpaca

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
49
Q

Most effective method of estrous synchronization in sows?

A

Weaning

50
Q

Order of follicular dynamics

A

1) Recruitment
2) Selection
3) Dominance
4) Atresia

51
Q

Luteal phase begins with

A

Ovulation

52
Q

Luteal phase ends with

A

Luteolysis

53
Q

The male hypothalamus does not have a

A

Surge center

54
Q

2 main factors impacting hypothalamic GnRH neuron development

A

1) Exposure to environmental or social cues
2) Threshold body size

55
Q

Considered the onset of puberty in the female

A

1) First confirmed pregnancy
2) First ovulation
3) First estrus

56
Q

Why can’t neurons in the surge center secrete much GnRH prior to puberty in the female?

A

Estradiol concentrations are too low

57
Q

Considered onset of puberty in the male

A

1) Age at first ejaculation
2) Age at first ejaculation with adequate spermatozoa
3) Age at first ejaculation with live spermatozoa

58
Q

Which hormone defeminizes the hypothalamus in the male during prenatal differentiation?

A

Testosterone

59
Q

Prior to puberty in females, low estradiol is due to

A

Little follicular growth

60
Q

Best definition for the onset of puberty in both males and females

A

To accomplish reproductive sucess

61
Q

After puberty in females, the surge center is responsible for

A

Preovulatory surge of GnRH

62
Q

In the male, testosterone is converted to estradiol via

A

Aromatase

63
Q

After puberty in the female, basal levels of GnRH are higher because

A

Pulse frequency increases

64
Q

If progesterone is high, which structure is present on the ovary?

A

CL

65
Q

Which phase of the estrous cycle is characterized by the CL formation and the beginning of P4 secretion?

A

Metestrus

66
Q

Which phase is characterized by sexual receptivity?

A

Estrus

67
Q

Causes of anestrus

A

1) Negative energy balance
2) Disease
3) Pregnancy
4) Season of the year
5) Lactation

68
Q

High levels of preovulatory estradiol engages the

A

Surge center

69
Q

In a cycling female, what physiological event must happen for the follicular phase/proestrus to begin

A

Luteolysis/removal of negative feedback

70
Q

Another name for the surge center

A

Preovulatory center

71
Q

How is LH regulated?

A

GnRH

72
Q

What hormone is produced by the CL?

A

Progesterone

73
Q

Luteolysis is caused by

A

Protsaglandin

74
Q

What are protein/peptide hormones?

A

Ex: Insulin; Act via plasma membrane receptors; Exert effects on the cytoplasm; cannot feed in their diet because protein will be absorbed.

75
Q

What are steroid hormones?

A

Ex: Progesterone & Testosterone; Act via nuclear receptors that regulate transcription factors - slow responses; act through plasma membrane receptors - rapid responses

76
Q

Sensory neurons

A

Afferent neurons taking neural signals to the spinal cord

77
Q

Efferent neurons

A

Taking neural signals from the spinal cord and to the target tissue

78
Q

Target tissues

A

Organs that respond to a specific set of stimuli or hormone

79
Q

What kind of reflex does a neurotransmitter have?

A

Simple neural reflex

80
Q

What kind of reflex does a neurohormone have?

A

Neuroendocrine reflex

81
Q

What does a simple neural reflex do?

A

The nerves release neurotransmitters directly to the target tissue

82
Q

What does a neuroendocrine reflex do?

A

Requires a neurohormone to enter the bloodstream and acts on remote target tissues

83
Q

What is the sella turcica?

A

A cavity in the sphenoid bone; develops in bone around the pituitary for protection

84
Q

What is the Hypothalamo-Hypophyseal Portal System?

A

Connects the hypothalamus to the anterior pituitary; Its main function is the transport and exchange of hormones to allow fast communication between both glands

85
Q

What is neurohypophysis?

A

A structure that is located at the base of the brain; it is the posterior lobe of the pituitary gland.

86
Q

Negative feedback = _____ of GnRH neurons

A

Suppression

87
Q

Positive feedback = _____ of GnRH neurons

A

Stimulation

88
Q

The surge center is sensitive to

A

positive feedback

89
Q

What are kisspeptins?

A

The “gatekeepers” for GnRH release; Neuropeptides by the hypothalamus; an important regulator of sexual differentiation of the brain

90
Q

What is the kisspeptins affected by?

A

Pheromones, stress, photoperiod, nutrition, age, etc.

91
Q

Reproductive hormones have short ____

A

Half-lives

92
Q

Reproductive hormones are classified by:

A

1) Source
2) Mode of action
3) Biochemical classification

93
Q

Reproductive Hormones: Source Example

A

Pituitary hormones (FHS, LH, Oxytocin, Prolactin)

94
Q

Reproductive Hormones: Mode of Action Example

A

Gonadotrophins (FHS, LH)

95
Q

Reproductive Hormones: Biochemical Classification Example

A

Glycoproteins (FSH, LH)

96
Q

Reproductive hormones originate from

A

1) Hypothalamus
2) Pituitary
3) Gonads (testis/ovaries)
4) Uterus
5) Placenta (if pregnant)

97
Q

Reproductive hormones can cause:

A

1) Release of other hormones
2) Stimulation of the gonads
3) Sexual promotion
4) Pregnancy maintenance
5) Luteolysis

98
Q

What is the hormone from the tissue of origin: Hypothalamus

A

GnRH

99
Q

What is the hormone from the tissue of origin: Pituitary

A

FSH, LH, & Prolactin

100
Q

What is the hormone from the tissue of origin: Gonadal

A

Estrogens, Progesterone, Inhibin, & Testosterone

101
Q

What is the mode of action of Neurohormones?

A

Synthesized by neurons - released directly into the blood to target tissues

102
Q

What is the mode of action of releasing hormones?

A

Synthesized by neurons in the hypothalamus

103
Q

What is the mode of action of gonadotropins?

A

FSH & LH

104
Q

What is the mode of action of sexual promoters?

A

Secreted by gonads

105
Q

What do sexual promoters do?

A

1) Stimulate the reproductive tract
2) Regulate the function of the hypothalamus
3) Regulate reproductive behavior
4) Development of secondary sex characteristics

106
Q

What is the mode of action of general metabolic hormones?

A

Promote metabolic well-being

107
Q

What is the mode of action of luteolytic hormones?

A

Destroy CL

108
Q

What is a pheromone?

A

Substances that are secreted to the outside of the body

109
Q

What detects pheromones?

A

The olfactory system by the vomeronasal organ

110
Q

Steroid hormones have what two types of receptors?

A

1) Fast response (similar pathway to protein hormones)
2) Slow response

111
Q

How does steroid transport work?

A

Transported in the blood by a complex system

112
Q

How does movement through the cell membrane and cytoplasm work?

A

Disassociates with transport proteins

113
Q

How does the binding of steroids to nuclear receptors work?

A

Similar to protein-receptor binding; initiates DNA-directed messenger RNA synthesis

114
Q

How does mRNA synthesis and protein synthesis work?

A

New mRNA leaves the nucleus and attaches to ribosomes

115
Q

What are the three patterns of hormone secretion?

A

1) Episodic
2) Basal
3) Sustained

116
Q

What is episodic secretion?

A

Associated with hormones under the nervous control; When nerves in the hypothalamus fire, neuropeptides are released in a sudden burst/pulse

117
Q

What is basal secretion?

A

Hormone level stays low, but fluctuates with low amplitude pulses; “Background noise”

118
Q

What is sustained secretion?

A

Hormone level remains elevated; Relatively steady, stable fashion for a long period of time; “Consistent”

119
Q

What are the four “strengths” of hormone action?

A

1) Pattern and duration of secretion
2) Half-life
3) Receptor density
4) Receptor-hormone affinity

120
Q

Hypothalamic GnRH neurons must be able to _______ BEFORE they can induce ovulation

A

Respond to estradiol

121
Q

How does testosterone cross the blood-brain barrier? How does it defeminize/kill the surge center?

A

Testosterone does not bind to anything, so it can easily cross the blood-brain barrier; Testosterone will convert/defeminize to estradiol which will then kill of the surge center

122
Q

How are females able to keep the surge center?

A

Females have no testis to secrete testosterone, so it cannot defeminize; estradiol binds to alpha-fetoprotein, so it cannot cross the blood-brain barrier

AN S 331 (2 decks)

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